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B & S Engine Mower Running Rough

Apr 24, 2017#1

K

Kennykenny

I have a Toro push mower 20332 that has a B & S engine 6.75 HP. I am having a problem getting the engine to start and then when it does start it runs rough. I have disassembled the carburetor and cleaned it thoughly and reassembled it. The spark plug is good and has been changed.

Any suggestions on anything else to try or what the problem could be?

Apr 25, 2017#2

primerbulb120

Kenny,

Glad to see you back again! Did you ever fix that Troy Bilt trimmer?

Could you get the model number off the mower engine for me? I looked up the mower model, but I'm not really clear on which type of Briggs and Stratton engine it has.

Thanks

Apr 25, 2017#3

K

Kennykenny

The model is 20332. Are you meaning the serial number? It is, 290088286. I did get the Troy-bilt fixed thanks to you....

Apr 25, 2017#4

primerbulb120

Kennykenny said:
The model is 20332. Are you meaning the serial number? It is, 290088286. I did get the Troy-bilt fixed thanks to you....

The mower and the engine have separate model numbers. This page from Briggs and Stratton shows you where to find the one on the engine:
https://www.briggsandstratton.com/na/en_us/support/need-help/push-mower-engines.html

Glad you got the Troybilt fixed! :thumbsup:

Apr 25, 2017#5

A

alitterit

Did you run a small piece of wire or anything through all the small passages/jets inside the carb while cleaning it? Just this past winter I was fixing a snowblower with the same issue and I could see through the jet when I held it up to the light but still had an issue once back together. Took it back apart ran a wire through everything and sure enough gunk was on the end of the wire after running it through one of the jets and it was just enough gunk left in there to cause an issue cause it ran just fine afterwards.

Apr 25, 2017#6

K

Kennykenny

primerbulb120 said:
The mower and the engine have separate model numbers. This page from Briggs and Stratton shows you where to find the one on the engine:
https://www.briggsandstratton.com/na/en_us/support/need-help/push-mower-engines.html

Glad you got the Troybilt fixed! :thumbsup:

Attached is the engine model number. Thanks for the help.

Apr 25, 2017#7

K

Kennykenny

alitterit said:
Did you run a small piece of wire or anything through all the small passages/jets inside the carb while cleaning it? Just this past winter I was fixing a snowblower with the same issue and I could see through the jet when I held it up to the light but still had an issue once back together. Took it back apart ran a wire through everything and sure enough gunk was on the end of the wire after running it through one of the jets and it was just enough gunk left in there to cause an issue cause it ran just fine afterwards.

I took apart the carb and soaked in carb cleaner and also took a pin and stuck it in the each hole in the cup bolt and the carb holes.

Apr 27, 2017#8

primerbulb120

When you say "runs rough." Does it sputter and pop, does it surge or does it do all of the above? Also, does it produce any smoke while running?

Apr 27, 2017#9

K

Kennykenny

primerbulb120 said:
When you say "runs rough." Does it sputter and pop, does it surge or does it do all of the above? Also, does it produce any smoke while running?

It is more or a sputter and the engine HP never gets to full power. I have been able to get the engine to start now after about 5 pulls but the power never gets to full speed. I am able to get the engine to rev up by manually moving the spring that moves the throttle above the carb. As mowing, the engine revving goes up and down. Speeds up a bit and lowers down a bit but never reaches a full consistent power sound.

Apr 27, 2017#10

primerbulb120

This is an autochoke engine, right? No primer bulb? If so, I think that's the problem. Either the autochoke linkage is hooked up wrong, or the actuator spring on the muffler has failed.

Apr 27, 2017#11

K

Kennykenny

primerbulb120 said:
This is an autochoke engine, right? No primer bulb? If so, I think that's the problem. Either the autochoke linkage is hooked up wrong, or the actuator spring on the muffler has failed.

Yes, it is an autochoke. No primer bulb. I am attaching pics of the engine/carb. The revving of the engine is surging and slowing down, surging and slowing down continously but not at full throttle. It doesn't normally run semi-smoothly upon initial start. As previously mentioned, the mower is hard to start and it takes a bit before it runs semi-smoothly at all.

You mentioned about either the autochoke linkage is hooked up wrong, or the actuator spring on the muffler has failed. If you still think that these are the issues after my additional information, is it possible to provide me how to on fixing these scenerios?

Thanks so much for your help!!

Apr 27, 2017#12

primerbulb120

Start the engine and try moving the autochoke lever manually to see if it makes a difference. The autochoke lever is the large, black plastic lever that opens and closes the choke valve on the carburetor. The choke should open when the engine starts and stay open as it runs. You can remove the air filter to verify that the choke is opening all the way. If it isn't opening all the way, that could be your problem.

I noticed in your second picture the linkage return spring is disconnected. (Stretched silver spring. This is not the actuator spring.) Did you disconnect it for pictures, or was it disconnected to begin with?

Apr 27, 2017#13

K

Kennykenny

primerbulb120 said:
Start the engine and try moving the autochoke lever manually to see if it makes a difference. The autochoke lever is the large, black plastic lever that opens and closes the choke valve on the carburetor. The choke should open when the engine starts and stay open as it runs. You can remove the air filter to verify that the choke is opening all the way. If it isn't opening all the way, that could be your problem.

I noticed in your second picture the linkage return spring is disconnected. (Stretched silver spring. This is not the actuator spring.) Did you disconnect it for pictures, or was it disconnected to begin with?

I had done as you said previously and moved the lever to open the choke valve. Opening the choke does help make the moter run at a higher RPM. When I let go the rpm goes down. Yes I did remove the spring to take the picture. It had been attached.

Apr 27, 2017#14

primerbulb120

If you start the mower and attach a zip tie to keep the choke open, will it run properly or does it still sputter?

(Just make sure you don't zip tie the throttle open - your engine could explode! The choke valve is the one nearest to the air filter. Throttle is closest to the engine.You probably already know this, but I'll mention it anyway in case some less knowledgeable person sees this thread.)

Apr 28, 2017#15

K

Kennykenny

primerbulb120 said:
If you start the mower and attach a zip tie to keep the choke open, will it run properly or does it still sputter?

(Just make sure you don't zip tie the throttle open - your engine could explode! The choke valve is the one nearest to the air filter. Throttle is closest to the engine.You probably already know this, but I'll mention it anyway in case some less knowledgeable person sees this thread.)

The choke valve is the flap inside of the carb that opens/closes? Right? You just have me wanting to make sure after your comment of the engine exploding...:smile:

Apr 28, 2017#16

primerbulb120

There are two flaps (butterfly valve is the technical name) in the carb. One is the throttle, other one is the choke. I circled them in the picture to show you which one is which.

The choke should be closed when the engine starts and all the way open when the engine is running. The engine won't start cold with the choke open, so what I would do is:

1. Zip tie the choke fully open.
2. Put a quick shot of starting fluid in the carb throat to prime the engine.
3. Start engine and see if it runs better.

Apr 28, 2017#17

K

Kennykenny

primerbulb120 said:
View attachment 31822

There are two flaps (butterfly valve is the technical name) in the carb. One is the throttle, other one is the choke. I circled them in the picture to show you which one is which.

The choke should be closed when the engine starts and all the way open when the engine is running. The engine won't start cold with the choke open, so what I would do is:

1. Zip tie the choke fully open.
2. Put a quick shot of starting fluid in the carb throat to prime the engine.
3. Start engine and see if it runs better.

Here is the pic using a zip tip following your directions. Following a couple squirts of carb cleaner inside of the carb, it took about 6 pulls to get the mower to start. I let the mower run for about 30-45 seconds. The engine ran the same way as it was doing prior, low rpm's, slow surging of the engine and then back down and then repeat. The only way that the rpm's would increase was to pull on the spring that is attached to the throttle, pulling the spring toward the front of the mower. I turned the mower off and tried to start the mower again(with the zip tie still keeping the carb flap open) and it wouldn't start. I sprayed more carb cleaner in the carb and it took about 10 pulls to start the engine and it ran the same way as before.

Thoughts? BTW, great visual that you provided in the last response. That helped a lot!!!

Apr 28, 2017#18

primerbulb120

Hitherto, I have been giving you one thing at a time to check. However, this is too slow of a process for both of us. Therefore, I will give you a list of all the things I would check. It may look intimidating, but it will probably take you less time to do everything than it has taken me to type this list. :wink:

1. Make sure the mower blade is installed properly and in good condition. Make sure the blade adpator cannot spin on the crankshaft. The mower blade acts as a secondary flywheel, and the mower will exhibit the symptoms you describe if the blade is missing or excessively worn. Be sure to tip the mower so that the carb is facing up to prevent oil from draining out the crankcase breather.

2. Did you drain and clean the gas tank before reinstalling the carburetor? If not, drain it and clean it with fresh gas. Make sure the fuel line is free of obstructions. Then drain the gas from the carburetor and re-assemble everything. Bad gas or an obstructed fuel line can cause the symptoms you describe.

3. Make sure the three inlets in the carburetor bowl bolt are all clear of obstructions. The passages within the bolt form a "T" . If one or more of them are clogged or obstructed the engine will exhibit the symptoms you describe.

4. Ensure that the spark plug is gapped correctly. I would set it at 0.025 inches.

5. Attach an inline spark tester to make sure the magneto is working properly. If you don't have an inline spark tester, skip this one for now, as it's one of the less likely causes.

6. Remove the muffler and see if the engine runs smoothly without it. If so, you have a clogged muffler.

7. Ensure that the O ring behind the carb is in good condition.
:thumbsup:
8. Inspect the intake tube (plastic tube from carb to engine) and ensure that it is free of cracks. Make sure the bolts holding it to the engine are not loose. You will have to remove the metal shroud to do this.

9. While you have the metal shroud removed, make sure there is no debris preventing the governor and throttle linkage from operating properly.

10. Inspect the head gasket to make sure it's not blown. Ensure that all cylinder head bolts are tight.

If none of these are the problem, I'll suspect one of three things: sheared flywheel key, bad carburetor or valves not seating properly.

If you could take a video of the engine running for me to listen to, that would also help. History of the problem would also help. (Did it begin while you were using the mower, or did it begin after the mower was in storage for a while?)

If you need any help with the items on my list, let me know. I assure you, these inspections/repairs are easier than they sound.:thumbsup:

Apr 28, 2017#19

K

Kennykenny

primerbulb120 said:
Hitherto, I have been giving you one thing at a time to check. However, this is too slow of a process for both of us. Therefore, I will give you a list of all the things I would check. It may look intimidating, but it will probably take you less time to do everything than it has taken me to type this list. :wink:

1. Make sure the mower blade is installed properly and in good condition. Make sure the blade adpator cannot spin on the crankshaft. The mower blade acts as a secondary flywheel, and the mower will exhibit the symptoms you describe if the blade is missing or excessively worn. Be sure to tip the mower so that the carb is facing up to prevent oil from draining out the crankcase breather.

2. Did you drain and clean the gas tank before reinstalling the carburetor? If not, drain it and clean it with fresh gas. Make sure the fuel line is free of obstructions. Then drain the gas from the carburetor and re-assemble everything. Bad gas or an obstructed fuel line can cause the symptoms you describe.

3. Make sure the three inlets in the carburetor bowl bolt are all clear of obstructions. The passages within the bolt form a "T" . If one or more of them are clogged or obstructed the engine will exhibit the symptoms you describe.

4. Ensure that the spark plug is gapped correctly. I would set it at 0.025 inches.

5. Attach an inline spark tester to make sure the magneto is working properly. If you don't have an inline spark tester, skip this one for now, as it's one of the less likely causes.

6. Remove the muffler and see if the engine runs smoothly without it. If so, you have a clogged muffler.

7. Ensure that the O ring behind the carb is in good condition.
:thumbsup:
8. Inspect the intake tube (plastic tube from carb to engine) and ensure that it is free of cracks. Make sure the bolts holding it to the engine are not loose. You will have to remove the metal shroud to do this.

9. While you have the metal shroud removed, make sure there is no debris preventing the governor and throttle linkage from operating properly.

10. Inspect the head gasket to make sure it's not blown. Ensure that all cylinder head bolts are tight.

If none of these are the problem, I'll suspect one of three things: sheared flywheel key, bad carburetor or valves not seating properly.

If you could take a video of the engine running for me to listen to, that would also help. History of the problem would also help. (Did it begin while you were using the mower, or did it begin after the mower was in storage for a while?)

If you need any help with the items on my list, let me know. I assure you, these inspections/repairs are easier than they sound.:thumbsup:

Thanks. I will let you know.

Apr 28, 2017#20

primerbulb120

I'll stay tuned. Whatever you do, don't assume that my list is too hard because it covers the whole page. :laughing:

Apr 30, 2017#21

K

Kennykenny

primerbulb120 said:
I'll stay tuned. Whatever you do, don't assume that my list is too hard because it covers the whole page. :laughing:

Primer,

I am working my way through your list. The diagnosis is going well. All looks goog thus far. Is it possible to give more detailed how to insturctions on how to do the checks on steps 8-10? I am not sure of some of the items that you are describing and how to proceed through these steps. Thank you.

8. Inspect the intake tube (plastic tube from carb to engine) and ensure that it is free of cracks. Make sure the bolts holding it to the engine are not loose. You will have to remove the metal shroud to do this.

9. While you have the metal shroud removed, make sure there is no debris preventing the governor and throttle linkage from operating properly.

10. Inspect the head gasket to make sure it's not blown. Ensure that all cylinder head bolts are tight.

Apr 30, 2017#22

primerbulb120

Kennykenny said:
Primer,

I am working my way through your list. The diagnosis is going well. All looks goog thus far. Is it possible to give more detailed how to insturctions on how to do the checks on steps 8-10? I am not sure of some of the items that you are describing and how to proceed through these steps. Thank you.

8. Inspect the intake tube (plastic tube from carb to engine) and ensure that it is free of cracks. Make sure the bolts holding it to the engine are not loose. You will have to remove the metal shroud to do this.

9. While you have the metal shroud removed, make sure there is no debris preventing the governor and throttle linkage from operating properly.

10. Inspect the head gasket to make sure it's not blown. Ensure that all cylinder head bolts are tight.

I've got to run now, but I'll give you more details after dinner. :thumbsup:

Apr 30, 2017#23

K

Kennykenny

primerbulb120 said:
I've got to run now, but I'll give you more details after dinner. :thumbsup:

:thumbsup:

Apr 30, 2017#24

primerbulb120

Okay, so judging by your pictures you already have the decorative plastic shroud off. Now you need to remove the metal shroud that covers the flywheel and cylinder. In order to do this, first you need to take off the gas tank. There are 4 bolts holding it on, 3 around the starter and one under the gas tank at the back of the engine. (It's on the carb side of the engine.) With the bolts removed, clamp the fuel line with a vice grips and disconnect it from the carburetor. Then you should be able to lift the gas tank off the shroud.

After removing the gas tank, you can remove the metal shroud. There are 5 bolts holding it on. Two are at the front of the engine, above the spark plug. Two are at the very back, holding the shroud onto the engine block. The other one holds the oil disptick on. Remove it and then rotate the dipstick assembly to get it out of the way. (It's just held onto the engine block by an O ring, so it should rotate easily. ) After this, you can pull the metal shroud off.

With the shroud removed, you will be able to access all the parts in steps 8 and 9. The plastic intake tube goes from the carburetor to the engine. Make sure it is in good shape and the bolts holding it to the engine are not loose.

You will also be able to see the governor linkage (number 9.) It consists of the parts connected to the throttle. Make sure it's free of debris and moving freely.

Step 10 is the head gasket. It's the gasket between the cylinder head and the engine. The cylinder head is the part that the spark plug screws into. The head bolts are the bolts around the spark plug. Make sure the head gasket doesn't have any obvious leaks or holes in it. Don't take the cylinder head off, just do the best you can with it attached.

Apr 30, 2017#25

K

Kennykenny

primerbulb120 said:
Okay, so judging by your pictures you already have the decorative plastic shroud off. Now you need to remove the metal shroud that covers the flywheel and cylinder. In order to do this, first you need to take off the gas tank. There are 4 bolts holding it on, 3 around the starter and one under the gas tank at the back of the engine. (It's on the carb side of the engine.) With the bolts removed, clamp the fuel line with a vice grips and disconnect it from the carburetor. Then you should be able to lift the gas tank off the shroud.

After removing the gas tank, you can remove the metal shroud. There are 5 bolts holding it on. Two are at the front of the engine, above the spark plug. Two are at the very back, holding the shroud onto the engine block. The other one holds the oil disptick on. Remove it and then rotate the dipstick assembly to get it out of the way. (It's just held onto the engine block by an O ring, so it should rotate easily. ) After this, you can pull the metal shroud off.

With the shroud removed, you will be able to access all the parts in steps 8 and 9. The plastic intake tube goes from the carburetor to the engine. Make sure it is in good shape and the bolts holding it to the engine are not loose.

You will also be able to see the governor linkage (number 9.) It consists of the parts connected to the throttle. Make sure it's free of debris and moving freely.

Step 10 is the head gasket. It's the gasket between the cylinder head and the engine. The cylinder head is the part that the spark plug screws into. The head bolts are the bolts around the spark plug. Make sure the head gasket doesn't have any obvious leaks or holes in it. Don't take the cylinder head off, just do the best you can with it attached.

Great instructions. I will check it out and let you know. Thank you!

May 1, 2017#26

K

Kennykenny

primerbulb120 said:
Okay, so judging by your pictures you already have the decorative plastic shroud off. Now you need to remove the metal shroud that covers the flywheel and cylinder. In order to do this, first you need to take off the gas tank. There are 4 bolts holding it on, 3 around the starter and one under the gas tank at the back of the engine. (It's on the carb side of the engine.) With the bolts removed, clamp the fuel line with a vice grips and disconnect it from the carburetor. Then you should be able to lift the gas tank off the shroud.

After removing the gas tank, you can remove the metal shroud. There are 5 bolts holding it on. Two are at the front of the engine, above the spark plug. Two are at the very back, holding the shroud onto the engine block. The other one holds the oil disptick on. Remove it and then rotate the dipstick assembly to get it out of the way. (It's just held onto the engine block by an O ring, so it should rotate easily. ) After this, you can pull the metal shroud off.

With the shroud removed, you will be able to access all the parts in steps 8 and 9. The plastic intake tube goes from the carburetor to the engine. Make sure it is in good shape and the bolts holding it to the engine are not loose.

You will also be able to see the governor linkage (number 9.) It consists of the parts connected to the throttle. Make sure it's free of debris and moving freely.

Step 10 is the head gasket. It's the gasket between the cylinder head and the engine. The cylinder head is the part that the spark plug screws into. The head bolts are the bolts around the spark plug. Make sure the head gasket doesn't have any obvious leaks or holes in it. Don't take the cylinder head off, just do the best you can with it attached.

Primer,

I have followed all of your steps(except for the inline spark tester-don't have one). Everything looked to be in good shape. I have cleaned up everthing that I could. Unfortunately I can not even get the mower to start now. I sprayed some carb cleaner in the carb and the mower tries to but does not. No carb cleaner, no luck at all attempting to start.

You previously asked when this started to happen, it began last fall, when mowing, but has continued this spring and I decided that it was time to address the problem. You also mentioned, a sheared flywheel key, bad carburetor or valves not seating properly. Are you still leaning toward those issues? If so, other than replacing with a new carb, how do I go about repairing the other two items? Thoughts?

May 1, 2017#27

primerbulb120

If it tries to starts and stalls with the carb cleaner but won't start at all without it, it must be a carb issue. I would replace the carb and see if that fixes it. You really don't want to get into the cylinder to check the valves unless it's absolutely necessary, as you're supposed to have a torque wrench to tighten the head bolts during reassembly. Checking the flywheel key is a difficult job as well.

Don't buy a carb just yet, let me look one up for you. You have to be careful as there are lots of junk Chinese carbs out there.

May 1, 2017#28

K

Kennykenny

primerbulb120 said:
If it tries to starts and stalls with the carb cleaner but won't start at all without it, it must be a carb issue. I would replace the carb and see if that fixes it. You really don't want to get into the cylinder to check the valves unless it's absolutely necessary, as you're supposed to have a torque wrench to tighten the head bolts during reassembly. Checking the flywheel key is a difficult job as well.

Don't buy a carb just yet, let me look one up for you. You have to be careful as there are lots of junk Chinese carbs out there.

Thanks so much!

May 2, 2017#29

U

unluckywithmowers

Hi, I definitely don't want to divert from this thread, especially since it sounds like you're getting pretty far along, but I think I'm having similar problems.
I submitted my problem as a new post.
I'm also certainly following your thread very closely. If it seems like there might be some overlap or any wisdom, I'd appreciate a look. I do seem to have a bit more success with the starting, but less success with the continued running. Happy to provide any other details anyone thinks might inform this thread in any way.

Thanks!

May 2, 2017#30

primerbulb120

If you decide to go with a new carburetor, here's the one I would get: https://www.amazon.com/Briggs-Stratton-799866-Carburetor-Replaces/dp/B00CNWWNGW

Might be worth a shot to try troubleshooting the old one before spending $32 on a new one, since I'm not 100% sure that the carb is your issue. As far as what's wrong with the current one, I'd suspect either the float or the needle seat. This is assuming that

- The gas tank contains fresh, new gas.
- The fuel line is not obstructed.
- The carburetor has been thoroughly cleaned otherwise.

When I clean/rebuild a carburetor of this type, I typically replace the following parts:

- Float
- Needle valve
- Both bowl gaskets
- Needle seat

These parts can be obtained by purchasing the following two kits:

http://www.ebay.com/itm/WALBRO-OEM-...ash=item41c3856d73:m:mitMQjpy0Jjt171UugWDZVA\
http://www.ebay.com/itm/GENUINE-Wal...960839?hash=item3f44211e87:g:A08AAOSwdIFX0dFG

Thanks for posting the history of the problem! Did it appear over time, did it appear all at once while mowing, or did it begin between mowings (mower ran fine one week and wouldn't start the next.)?

May 2, 2017#31

K

Kennykenny

primerbulb120 said:
If you decide to go with a new carburetor, here's the one I would get: https://www.amazon.com/Briggs-Stratton-799866-Carburetor-Replaces/dp/B00CNWWNGW

Might be worth a shot to try troubleshooting the old one before spending $32 on a new one, since I'm not 100% sure that the carb is your issue. As far as what's wrong with the current one, I'd suspect either the float or the needle seat. This is assuming that

- The gas tank contains fresh, new gas.
- The fuel line is not obstructed.
- The carburetor has been thoroughly cleaned otherwise.

When I clean/rebuild a carburetor of this type, I typically replace the following parts:

- Float
- Needle valve
- Both bowl gaskets
- Needle seat

These parts can be obtained by purchasing the following two kits:

http://www.ebay.com/itm/WALBRO-OEM-...ash=item41c3856d73:m:mitMQjpy0Jjt171UugWDZVA\
http://www.ebay.com/itm/GENUINE-Wal...960839?hash=item3f44211e87:g:A08AAOSwdIFX0dFG

Thanks for posting the history of the problem! Did it appear over time, did it appear all at once while mowing, or did it begin between mowings (mower ran fine one week and wouldn't start the next.)?

Is it just as cost effective to purchase a new carb vs buying pieces?

May 2, 2017#32

primerbulb120

Around $12-$15 for the parts, $32 for a new carb.

May 2, 2017#33

primerbulb120

With your situation, after considering it some more I would recommend the new carb. With the new carb there's no chance something else in the carb is clogged or broken. :thumbsup: And you also have to consider the labor involved to fix the old carb.

If you were closer, I would tell you to go and pull the carb off the running Toro Recycler behind my shop and put it on yours to see if that fixes it. Unfortunately you live too far away. :frown:

May 2, 2017#34

K

Kennykenny

primerbulb120 said:
With your situation, after considering it some more I would recommend the new carb. With the new carb there's no chance something else in the carb is clogged or broken. :thumbsup: And you also have to consider the labor involved to fix the old carb.

If you were closer, I would tell you to go and pull the carb off the running Toro Recycler behind my shop and put it on yours to see if that fixes it. Unfortunately you live too far away. :frown:

I agree with your idea about the labor of a new one vs rebuilding and piecing an old one. To answer some of your followup questions:

Did it appear over time(Yes did appear over time), did it appear all at once while mowing(No), or did it begin between mowings (mower ran fine one week and wouldn't start the next.)-(No, once it started to run poorly--surging fast and slow, fast and slow, it has continued since).

- The gas tank contains fresh, new gas.--Yes I have put in new gas and oil when I went through your diagnosis checklist
- The fuel line is not obstructed.---assuning that the fuel line is the rubber hose from the gas tank to the side if the carb--no, it is clear, I checked that.
- The carburetor has been thoroughly cleaned otherwise.---cleaned well twice.

May 2, 2017#35

K

Kennykenny

primerbulb120 said:
If you decide to go with a new carburetor, here's the one I would get: https://www.amazon.com/Briggs-Stratton-799866-Carburetor-Replaces/dp/B00CNWWNGW

Might be worth a shot to try troubleshooting the old one before spending $32 on a new one, since I'm not 100% sure that the carb is your issue. As far as what's wrong with the current one, I'd suspect either the float or the needle seat. This is assuming that

- The gas tank contains fresh, new gas.
- The fuel line is not obstructed.
- The carburetor has been thoroughly cleaned otherwise.

When I clean/rebuild a carburetor of this type, I typically replace the following parts:

- Float
- Needle valve
- Both bowl gaskets
- Needle seat

These parts can be obtained by purchasing the following two kits:

http://www.ebay.com/itm/WALBRO-OEM-...ash=item41c3856d73:m:mitMQjpy0Jjt171UugWDZVA\
http://www.ebay.com/itm/GENUINE-Wal...960839?hash=item3f44211e87:g:A08AAOSwdIFX0dFG

Thanks for posting the history of the problem! Did it appear over time, did it appear all at once while mowing, or did it begin between mowings (mower ran fine one week and wouldn't start the next.)?

The link that you provided for the carb led me to a used carb. I am assuming that it is not the one that you were suggesting? I saw the following one on Amazon for $32, https://www.amazon.com/Briggs-Strat...tton+799866+Carburetor+Replaces+796707+794304

Is this the new one that you were suggesting?

May 2, 2017#36

B

BRYANB

Kennykenny said:
I have a Toro push mower 20332 that has a B & S engine 6.75 HP. I am having a problem getting the engine to start and then when it does start it runs rough. I have disassembled the carburetor and cleaned it thoughly and reassembled it. The spark plug is good and has been changed.

Any suggestions on anything else to try or what the problem could be?

DOES IT HAVE THE BOWL WITH THE FLOAT OR DOES IT HA A DIAPHRAM

May 2, 2017#37

B

BRYANB

IF IT HAS THE BOWL WITH THE FLOAT CHECK THE NEEDLE AND SEAT BUT I THINK IT'S THE BREATHER IN THE BOLT THAT HOLDS THE BOWL IT HAS BREATHER HOLES I CLEAN MINE WITH A PAPER CLIP OR AN OLD BREAD TIE

May 2, 2017#38

K

Kennykenny

BRYANB said:
IF IT HAS THE BOWL WITH THE FLOAT CHECK THE NEEDLE AND SEAT BUT I THINK IT'S THE BREATHER IN THE BOLT THAT HOLDS THE BOWL IT HAS BREATHER HOLES I CLEAN MINE WITH A PAPER CLIP OR AN OLD BREAD TIE

It has the float etc. I have cleaned the holes of the bolt a couple of times with no change.

May 2, 2017#39

primerbulb120

Kennykenny said:
The link that you provided for the carb led me to a used carb. I am assuming that it is not the one that you were suggesting? I saw the following one on Amazon for $32, https://www.amazon.com/Briggs-Strat...tton+799866+Carburetor+Replaces+796707+794304

Is this the new one that you were suggesting?

That's weird, when I click the link it gives me a new one. :confused2: The one I was recommending is part number 799866. Price is $32.12.

This engine really has me confused. It's got to be the carb, valves or flywheel key, but I'm not sure which one is the problem. :confused2:

My first guess is carb for the following reasons:

- Valves on these engines typically don't go out of adjustment. Neither have I encountered many of these engines with sticking valves.

-Flywheel keys typically don't shear for no reason. Normally they shear after you hit something with the mower, and a sheared key typically causes sharp kickback when you try to start the engine.

May 2, 2017#40

B

BRYANB

Kennykenny said:
It has the float etc. I have cleaned the holes of the bolt a couple of times with no change.

HOW OLD IS THE GAS CAP SOMETIMES THEY CANT BREATH AN CAUSES A VAPOR LOCK

May 2, 2017#41

K

Kennykenny

BRYANB said:
HOW OLD IS THE GAS CAP SOMETIMES THEY CANT BREATH AN CAUSES A VAPOR LOCK

original cap. think that might be the problem?

May 2, 2017#42

B

BRYANB

Kennykenny said:
original cap. think that might be the problem?

IT COULD BE, SOMETIMES WE OVERLOOK THE SIMPLE THINGS

May 3, 2017#43

primerbulb120

If it was the gas cap, the engine would start, run fine for a while and then stall. It would not exhibit a no start condition, and it would run great when the gas cap was loosened.

May 3, 2017#44

K

Kennykenny

primerbulb120 said:
If it was the gas cap, the engine would start, run fine for a while and then stall. It would not exhibit a no start condition, and it would run great when the gas cap was loosened.

Ordered the new carb. We'll see in a couple days whether or not this solves the issue. Will let you know. Cross your fingers....:thumbsup:

May 3, 2017#45

primerbulb120

:thumbsup:

May 4, 2017#46

K

Kennykenny

primerbulb120 said:
:thumbsup:

It Works!!!!:smile: Awesome diagnosis and assistance!!!! It now starts on the first pull. It hasn't done that since the mower was new. Only one tiny issue, the attached pic is a small part that fall off and I am not sure where it goes. ???? Thanks again....

May 4, 2017#47

primerbulb120

Yes!!! :thumbsup::biggrin:

Glad it's working now! That was a hard one to diagnose. Briggs carburetors are typically easy to clean, maybe yours had something else wrong with it. If it was a Tecumseh engine, replacing the carburetor would have been my first suggestion. Tecumseh carbs are nearly impossible to rebuild correctly.

Don't know where the part came from though. I'll take a look at my Toro tomorrow and see if I can figure out where it came from. (If I remember, that is. Don't hesitate to keep reminding me. :laughing

May 4, 2017#48

K

Kennykenny

primerbulb120 said:
Yes!!! :thumbsup::biggrin: Glad it's working now! That was a hard one to diagnose. Briggs carburetors are typically easy to clean, maybe yours had something else wrong with it. If it was a Tecumseh engine, replacing the carburetor would have been my first suggestion. Tecumseh carbs are nearly impossible to rebuild correctly.

Don't know where the part came from though. I'll take a look at my Toro tomorrow and see if I can figure out where it came from. (If I remember, that is. Don't hesitate to keep reminding me. :laughing

Excellent thanks. I am thinking that the part came from the air filter area but am not sure.

May 5, 2017#49

K

Kennykenny

primerbulb120 said:
Yes!!! :thumbsup::biggrin: Glad it's working now! That was a hard one to diagnose. Briggs carburetors are typically easy to clean, maybe yours had something else wrong with it. If it was a Tecumseh engine, replacing the carburetor would have been my first suggestion. Tecumseh carbs are nearly impossible to rebuild correctly.

Don't know where the part came from though. I'll take a look at my Toro tomorrow and see if I can figure out where it came from. (If I remember, that is. Don't hesitate to keep reminding me. :laughing

Primer,,

Checking in, any luck figuring out where the pictured part went on my mower?

May 6, 2017#50

primerbulb120

Haven't got a chance to check my mower yet. I did look up the parts list and I'm not seeing it.

I think it's either

A. Not part of your mower
B. A broken piece from a larger part.

Keep reminding me and I'll eventually check my mower. :laughing:

May 6, 2017#51

K

Kennykenny

Thanks. I really do think that it is part of my mower...Thanks for checking.

May 8, 2017#52

BlazNT

It looks like a part to hold a relay on to your engine or frame.

May 8, 2017#53

primerbulb120

I looked on my mower, and I'm not seeing it. :confused3:

As long as the mower runs, I wouldn't worry about it. :thumbsup:

May 8, 2017#54

K

Kennykenny

primerbulb120 said:
I looked on my mower, and I'm not seeing it. :confused3:

As long as the mower runs, I wouldn't worry about it. :thumbsup:

Agree.....was just hoping to put it all back together. Thanks for the followup.

May 8, 2017#55

primerbulb120

My guess is that it's part of one of the sheet metal shrouds on your engine. It probably got broken off during repair. The engine should operate just fine without it, it's probably used for attaching one of the optional features that your engine does not have.

May 10, 2017#56

U

unluckywithmowers

primerbulb120 said:
If you decide to go with a new carburetor, here's the one I would get: https://www.amazon.com/Briggs-Stratton-799866-Carburetor-Replaces/dp/B00CNWWNGW

Kennykenny said:
It Works!!!!

I see your problem got resolved, congratulations! I just wanted to post in here an extra thank you to the diagnosers for the suggestions, as well as a thank you to the legwork by Kennykenny for trying all of the suggestions. Your efforts helped me resolve my similar issue the same way (replaced carburetor).
Thanks everyone!

May 10, 2017#57

K

Kennykenny

unluckywithmowers said:
I see your problem got resolved, congratulations! I just wanted to post in here an extra thank you to the diagnosers for the suggestions, as well as a thank you to the legwork by Kennykenny for trying all of the suggestions. Your efforts helped me resolve my similar issue the same way (replaced carburetor).
Thanks everyone!

Agreed....the help was awesome. This site is great. I will be back on it again soon as I am needing some advice on a Stihl blower. :wink:

May 11, 2017#58

primerbulb120

unluckywithmowers said:
I see your problem got resolved, congratulations! I just wanted to post in here an extra thank you to the diagnosers for the suggestions, as well as a thank you to the legwork by Kennykenny for trying all of the suggestions. Your efforts helped me resolve my similar issue the same way (replaced carburetor).
Thanks everyone!

:thumbsup:

May 21, 2017#59

K

Kennykenny

Help!!! The same lawn mower still has issues. Upon using the mower for the third time since the replacement of the carb, other issues have begun. I started the mower,
it took 4-5 pulls to start. The RPM's was running really fast and it seemed very loud. The mower ran for about five minutes and then the RPM's dropped very slow. The mower did not die but it sounded like it was going to. The mower was also sputtering a bit off and on. I countinued to mow hoping that things would "fix itself" and I could just move on with the mowing. The RPM's continued to run slow and the mower did eventually die. I could not immediately get the mower to start on the lawn. I moved the mower to the flat driveway and the mower started after 3-4 pulls. The mower once again ran with a high RPM and then dropped slow. The mower continued to do this 4-5 times until I finally gave up and borrowed a mower to finish. :thumbdown:

I did just remove the blade and shapened and balanced it. I reinstalled it correctly(it appears). I just say this in case for some remote possibility that this could help lead to any problem.

Any new diagnosis? Very frustrating.......

May 21, 2017#60

primerbulb120

Make sure all the governor linkage and springs are still connected.

May 21, 2017#61

K

Kennykenny

primerbulb120 said:
Make sure all the governor linkage and springs are still connected.

All connected as far as it looks to me.

May 21, 2017#62

primerbulb120

According to your picture, the throttle valve is not hooked up to anything. Thus, it is randomly vibrating around and causing the engine to run at random speeds. I'm on my tablet so I can't circle the problem, but here's a page that shows how everything is supposed to be attached. Note that the engine pictured does not have autochoke.

Compare it to your picture and I think you'll see the problem. http://outdoorpowerinfo.com/repairs/briggs_lms_carb_linkages.asp Don't follow any of the instructions on the page, just hook up the linkage the way it's shown.

I'm surprised the mower ran long enough for you to use it the first two times!

May 21, 2017#63

cpurvis

I'll try to do it for you.

The rod with the small red circle around it has and end that is not visible in this picture. That end goes in the hole in the throttle shaft in the big red circle.

I think.

May 21, 2017#64

primerbulb120

cpurvis, You nailed it. :thumbsup:

May 21, 2017#65

K

Kennykenny

primerbulb120 said:
According to your picture, the throttle valve is not hooked up to anything. Thus, it is randomly vibrating around and causing the engine to run at random speeds. I'm on my tablet so I can't circle the problem, but here's a page that shows how everything is supposed to be attached. Note that the engine pictured does not have autochoke.

Compare it to your picture and I think you'll see the problem. http://outdoorpowerinfo.com/repairs/briggs_lms_carb_linkages.asp Don't follow any of the instructions on the page, just hook up the linkage the way it's shown.

I'm surprised the mower ran long enough for you to use it the first two times!

Wow, really??? How could I have missed that....If I had not put that back in place when I put on the new carb, like you say, I am surprised that I would have gotten a few mowings out of it. I will put that back on and let you know how it goes.

May 22, 2017#66

primerbulb120

I'm guilty of missing it a few times as well. :ashamed:

May 28, 2017#67

K

Kennykenny

primerbulb120 said:
I'm guilty of missing it a few times as well. :ashamed:

My misery with the Toro mower continues. The mower ia finally running smooth. Now I go to start it and no luck. Upon looking over the mower I notice the slack in the cable and a hanging spring under the handle(both in the pics). I am assuming that this is now my new problem. I am assuming that thiis is causing there not to be enough gas to going to the carb.(?)

How do I go about fixing this one? Any idea what part number for the spring or at least the name of it so I know what to look for to get one?

I think that this mower is possessed.

May 28, 2017#68

cpurvis

I think that cable controls the blade brake and kill switch.

I'm not sure that spring is broken, either.

May 28, 2017#69

K

Kennykenny

Attached is another pic. I know that the spring controls the cable that has slag in it now. When I used a vice grip to move the cable toward the front of the mower(as in the picture) and had someone else pull the rope, the engine started.

I am still attempting to figure out the name of the broken spring and how to replace it. Any help?

May 28, 2017#70

primerbulb120

Here's what's going on:

1. The cable that connects to the engine is basically a kill switch. The other end is connected to the operator presence bar (the bar you release to stop the mower.) In your case, the cable has come loose from it's mount on the handle, so when you hold the bar down it doesn't put tension on the cable. See the white zip tie on the handle? It's hanging next to a plastic bracket. The plastic bracket has a large hole in the top, parallel to the cable. I'm not sure how the cable got out of that hole, but it needs to be going through that hole in order for the mechanism to work properly. Disconnect it at the engine (easier than doing it at the handle) and thread it through the hole. Then hook it back up to the engine. If cpurvis sees this, hopefully he can circle the parts I'm talking about. I'm on my tablet again and can't edit pictures.

2. The broken spring (yes, it is broken) has nothing to do with the engine not starting. It's part of the self propel mechanism. Unless the self propel systems starts acting weird (the mower doesn't want to stop moving) I would leave it alone. I think I disconnected that spring on my old Toro to make it easier to operate, and I don't remember having any issues as a result.

May 28, 2017#71

cpurvis

Cable (circled in blue) must go through the 'holder' (circled in red). That cable should attach firmly to the holder. That might be what the zip tie is for, although I've put zip ties on handlebars to hold the operator presence bar in place so as to not have to keep restarting the engine. But this one is in the wrong place to do that.

Hope this helps.

May 28, 2017#72

K

Kennykenny

primerbulb120 said:
Here's what's going on:

1. The cable that connects to the engine is basically a kill switch. The other end is connected to the operator presence bar (the bar you release to stop the mower.) In your case, the cable has come loose from it's mount on the handle, so when you hold the bar down it doesn't put tension on the cable. See the white zip tie on the handle? It's hanging next to a plastic bracket. The plastic bracket has a large hole in the top, parallel to the cable. I'm not sure how the cable got out of that hole, but it needs to be going through that hole in order for the mechanism to work properly. Disconnect it at the engine (easier than doing it at the handle) and thread it through the hole. Then hook it back up to the engine. If cpurvis sees this, hopefully he can circle the parts I'm talking about. I'm on my tablet again and can't edit pictures.

2. The broken spring (yes, it is broken) has nothing to do with the engine not starting. It's part of the self propel mechanism. Unless the self propel systems starts acting weird (the mower doesn't want to stop moving) I would leave it alone. I think I disconnected that spring on my old Toro to make it easier to operate, and I don't remember having any issues as a result.

I will give it a try tomorrow. Yes pictures are always the best for me :wink: Without having the mower in front of me while reading your note, everthing that you menion doesn't totally click. One thing is, Disconnect it at the engine--Where does it disconnect at the engine? Thanks as always for your help!!

May 28, 2017#73

K

Kennykenny

cpurvis said:
Cable (circled in blue) must go through the 'holder' (circled in red). That cable should attach firmly to the holder. That might be what the zip tie is for, although I've put zip ties on handlebars to hold the operator presence bar in place so as to not have to keep restarting the engine. But this one is in the wrong place to do that.

Hope this helps.View attachment 32400

Thank you for the picture. The zip tie has nothing to do with anything. I should have cut and removed, just didn't do it.

May 29, 2017#74

BlazNT

Model number of the mower? You may have posted it already but I am too lazy to find it.

May 29, 2017#75

primerbulb120

cpurvis said:
Cable (circled in blue) must go through the 'holder' (circled in red). That cable should attach firmly to the holder. That might be what the zip tie is for, although I've put zip ties on handlebars to hold the operator presence bar in place so as to not have to keep restarting the engine. But this one is in the wrong place to do that.

Hope this helps.View attachment 32400

Thanks!

Just one correction though: the cable doesn't attach firmly to the holder, it's supposed to be able to slide in the holder.

May 29, 2017#76

primerbulb120

Go back to the picture you attached in post 69. That's a picture of the cable where it connects to the engine.

May 29, 2017#77

K

Kennykenny

BlazNT said:
Model number of the mower? You may have posted it already but I am too lazy to find it.

20332

May 29, 2017#78

cpurvis

primerbulb120 said:
Thanks! Just one correction though: the cable doesn't attach firmly to the holder, it's supposed to be able to slide in the holder.

The cable housing doesn't slide in the holder, does it? I don't see how a cable can work if the housing is free to move.

May 29, 2017#79

K

Kennykenny

cpurvis said:
The cable housing doesn't slide in the holder, does it? I don't see how a cable can work if the housing is free to move.

That is kind of what I was thinking. I understand the part about unhooking from the engine piece(shown in #69). Then the cable goes throught the housing on the handle and reattached on the engine piece and that's it?

May 29, 2017#80

cpurvis

That is indeed 'it' if the final result is that the kill switch/blade brake lever on the engine moves forward when the operator presence handle is in the "run" position.

May 29, 2017#81

BlazNT

Spring is broken. Part number 114-7924

May 29, 2017#82

K

Kennykenny

cpurvis said:
The cable housing doesn't slide in the holder, does it? I don't see how a cable can work if the housing is free to move.

I guess I am still a bit confused about how there is tension on the cable when, as you stated in this post, " I don't see how a cable can work if the housing is free to move."

May 29, 2017#83

cpurvis

Kennykenny said:
I guess I am still a bit confused about how there is tension on the cable when, as you stated in this post, " I don't see how a cable can work if the housing is free to move."

I think primerbulb120 may be right.

This "cable" arrangement works differently than a normal cable. In a normal cable, the cable itself is what moves whatever it is that needs to be moved. In this application, the cable housing is what does the work. Since the end of the cable is fastened to an immovable fitting on the engine, when one operates the operator presence bar, the cable itself is trying to pull on something that can't move. Because the cable end cannot move, the cable housing must move toward the cable end. When it does, it pushes the moveable kill switch/blade brake lever on the engine.

So I think primerbulb120 is exactly right--the cable housing must be free to move. Not loose in space as it is now, but held in its holder in a manner which lets it slide forward.

When you think about it, this is a pretty ingenious use of a cable. I would have never thought of it but it saves a lot of cable length and also having to make a 180 degree bend in the cable if it were to be used in a normal fashion.

May 29, 2017#84

K

Kennykenny

cpurvis said:
I think primerbulb120 may be right.

This "cable" arrangement works differently than a normal cable. In a normal cable, the cable itself is what moves whatever it is that needs to be moved. In this application, the cable housing is what does the work. Since the end of the cable is fastened to an immovable fitting on the engine, when one operates the operator presence bar, the cable itself is trying to pull on something that can't move. Because the cable end cannot move, the cable housing must move toward the cable end. When it does, it pushes the moveable kill switch/blade brake lever on the engine.

So I think primerbulb120 is exactly right--the cable housing must be free to move. Not loose in space as it is now, but held in its holder in a manner which lets it slide forward.

When you think about it, this is a pretty ingenious use of a cable. I would have never thought of it but it saves a lot of cable length and also having to make a 180 degree bend in the cable if it were to be used in a normal fashion.

I got it!!! Back in business. Thank you to all for the assistance.:thumbsup:

May 29, 2017#85

primerbulb120

:dance1::thumbsup:

The cable housing has to slide freely in that plastic holder on the handle. Reason being, the Personal Pace mechanism slides up and down on the handle, and the cable is attached to the Personal Pace mechanism. If the cable was secured firmly to the handle, you wouldn't be able to activate the self propel.

Oct 16, 2017#86

K

Kennykenny

primerbulb120 said:
:dance1::thumbsup:

The cable housing has to slide freely in that plastic holder on the handle. Reason being, the Personal Pace mechanism slides up and down on the handle, and the cable is attached to the Personal Pace mechanism. If the cable was secured firmly to the handle, you wouldn't be able to activate the self propel.

Hey Primer, I'm back again with the same mower and more issues. The mower ran throughout this mowing season but I now can't get it to start at all. I pull and pull with no luck. I replaced the spark plug with a brand new one recently and believe it or not it started once but after that one time I couldn't get it to start again.

What suggestions do you have of something that I can try? Thanks!

Oct 17, 2017#87

Boudreaux In Eunice La.

I have read all 8 pages of this saga. Wow what a pisser for you to go thru all that and now it doesn't run ~!~!

Do you have spark ?? If you don't then your cable is more than likely bad. The cable you have to use to start and kill the mower when you take your hand off of the handle. It is not traveling all the way.

That is one likely thing............ If you have spark then take the air filter off and squirt GAS in the carb with a old DAWN bottle. It will give you a good straight squirt in the carb. NEVER EVER use starting fluid.

If your choke is closed open it by hand and squirt the gas in it. Try to start it. If it don't start then you have a compression issue. Maybe ................

Did you take the head off the engine ?? If you did you should have put a new gasket on it and torqued it to specs.

Let us know Mon Ami ~!~!

Oct 19, 2017#88

K

Kennykenny

Boudreaux In Eunice La. said:
I have read all 8 pages of this saga. Wow what a pisser for you to go thru all that and now it doesn't run ~!~!

Do you have spark ?? If you don't then your cable is more than likely bad. The cable you have to use to start and kill the mower when you take your hand off of the handle. It is not traveling all the way.

That is one likely thing............ If you have spark then take the air filter off and squirt GAS in the carb with a old DAWN bottle. It will give you a good straight squirt in the carb. NEVER EVER use starting fluid.

If your choke is closed open it by hand and squirt the gas in it. Try to start it. If it don't start then you have a compression issue. Maybe ................

Did you take the head off the engine ?? If you did you should have put a new gasket on it and torqued it to specs.

Let us know Mon Ami ~!~!

I checked for spark...had a spark. I squirted gas in the carb. The mower started for a second or two and then died and wouldn't start again. No, I did not remove the head off of the engine.

Oct 19, 2017#89

Boudreaux In Eunice La.

Time for another carb clean Are you taking the old seat out when you put a kit in it ??

Oct 19, 2017#90

primerbulb120

Kennykenny said:
I checked for spark...had a spark. I squirted gas in the carb. The mower started for a second or two and then died and wouldn't start again. No, I did not remove the head off of the engine.

Sorry, didn't see this thread until now. By "wouldn't start again", you mean that it won't fire at all even if you give it starting fluid?

Oct 19, 2017#91

K

Kennykenny

Boudreaux In Eunice La. said:
Time for another carb clean Are you taking the old seat out when you put a kit in it ??

Sorry but which part is considered the "seat?" When I replaced the carburetor this past spring, I replace the entire carburetor, it was one kit. Is the seat considered one of the
rubber gaskets?

Oct 19, 2017#92

K

Kennykenny

primerbulb120 said:
Sorry, didn't see this thread until now. By "wouldn't start again", you mean that it won't fire at all even if you give it starting fluid?

No worries Primer. The mower fired up for a couple of seconds after I sprayed gas, not starter fluid, in the carb as suggested. Then died and wouldn't restart.

Oct 19, 2017#93

Boudreaux In Eunice La.

Something is up with the carb take the bowl nut off and clean the holes in it and wipe the bowl out good.

Let us know ~!~!

Oct 20, 2017#94

K

Kennykenny

Boudreaux In Eunice La. said:
Something is up with the carb take the bowl nut off and clean the holes in it and wipe the bowl out good.

Let us know ~!~!

I took the carburetor apart and it seemed to be spotless since it was fairly new. I also cleared out the fuel line while I had it taken off the carburetor. It was clean too but cleaned it anyway. Put it all back together and the mower now starts. Not sure exactly what the problem seemed to be but I guess it was one of the things that I checked and cleaned. Thanks for the advice. I hope I don't have to check back with you guys again anytime soon on this mower.

Oct 21, 2017#95

B

Bill95

You checked the flywheel key Right?
You could do a leak down test to see if you have a leak in a seal or gasket.
Clean and gap your Valves?

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