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First time posting and I hope someone here can help me with my mystery problem.

Craftsman 917.258671
Briggs & Straton 19.5
Model 42E707
Type 1631-01
Code 9706065B

Problem: I am able to start the mower when cold. Once it warms up, if you decide to stop the mower for any reason, it will turn over but it will not restart until it has sat for several hours. My local Land and Coats advised it might be the Coil which I purchased and replaced. Unfortunately, the problem still exists. I have used this mower for years and this is the first problem I have had with it.

Has anyone else experienced an issue like this in the past? I have seen many people reference that the values could need adjustment on OHV motors but from my research I do not see where I have a rocker arm to adjust on the 42E707.

If anyone else has experienced an issue like this, please let me know what you did to fix your issue.

Thank you in advance for your assistance.

Craftsman46

Have you tried adding choke when trying to start? Or reducing throttle? Or both?

Also take off engine cover and clean out all grass and dirt from cooling fins.

BlazNT said:

Have you tried adding choke when trying to start? Or reducing throttle? Or both?

Click to expand...

Yes. Sorry, I have attempted to adjust the choke and throttle when attempting to restart. No lucky.

The only way to get it to restart is to let it sit until it is ice cold. This past weekend it wouldn't start even cold. I changed the coil thinking that was it and it started first try. After I mowed my yard and my other two neighbors yards, I turned it off thinking my problem was gone and sure enough it was still there. I had to push it to the shed.

BlazNT said:

Also take off engine cover and clean out all grass and dirt from cooling fins.

Click to expand...

When I changed the coil, I checked and I was clean on all cooling fins.

IF and a big IF somehow you do have an over heating engine and IF (especially ) the "coil" is sitting relatively close to the head it is possibly the over heat is killing the "coils" (by this I mean an "electronic module" with fairly fragile semiconductors inside ). Since I do not not know your model and do not know what style ignition you have I should probably just shut up which I will do shortly. IF you have coil only comprised of wound wire it would not die like an electronic module in over heat. What you describe might somehow be a fuel feed problem. If you know what a "proper" plug color is tell us what you have. The living after cold soak makes one think of a semiconductor (like a transistor) which will appear to live at cold , but really be dead at hot, like a zombie.

What should I be looking for when I check the plug color? I pulled both this weekend and neither appeared to be burnt or have excessive carbon build up.

Before everyone chimes in and loads you up with their favourite failure mode lets see if we can cut down the possabilities by 50%

Get an in line spark tester, one of the nenon tube types that plugs into the end of the spark plug lead.
Hook it up and if necessary use some cable ties to keep it off exhaust pipes.
When the mower will not start flip the hood and see if you are getting spark.

And to pick your memory, does the mower exhibit any other problems when running?
If you do not turn it off, does it stop all by itself ?

Welcome to the forum and thank you for posting all the relevant numbers first up.

Thanks, color sounds normal

bertsmobile1 said:

Before everyone chimes in and loads you up with their favourite failure mode lets see if we can cut down the possabilities by 50%

Get an in line spark tester, one of the nenon tube types that plugs into the end of the spark plug lead.
Hook it up and if necessary use some cable ties to keep it off exhaust pipes.
When the mower will not start flip the hood and see if you are getting spark.

And to pick your memory, does the mower exhibit any other problems when running?
If you do not turn it off, does it stop all by itself ?

Welcome to the forum and thank you for posting all the relevant numbers first up.

Click to expand...

@bertsmobile1 - I will look into sourcing a spark tester.

The only issue I can think of came after I parked the mower outside for two days when I was building my shed. The mower got wet one night from a rain storm but I didn't think it would hurt it to get we one time in 19 years.

When I went to start the mower I had trouble getting it to fire up immediately. I did notice that I had to have the choke pulled out about 1/4 of the way to keep it running long enough to drive back to the front yard and back in the garage. The very next week I mowed without any issues however I never turned the mower off until I was done mowing. My issue became painfully clear when I started using the bagger attachment in the fall to pick up leaves. I started noticing a slight sputter / loss of power if I didnt pull the choke out 1/4 of the way as I was under full power. When I would stop the mower to dump the leaves, I was done for the day as I couldn't get the mower to restart when it was hot.

I will add more if I think of it. I hope this helps!

Thanks!

Needing to pull the choke on to get clean running indicates a lean fuel situation in the engine.
This can be an air leak anywhere after the emulsion tube ( brass tube which sticks up in the carb.)
A low float level in the carb
Insufficient fuel supply to the carb.

If this is still happening the engine running lean will generate way too much heat for it to dissipate and that can cause it to be very difficult to restart but usually pulling the choke on full alleviates this situation.
Note it does not fix the problem , just works around it.

However I will wait for the spark test first.
The important thing is you only change 1 thing at a time or every one ends up really confused.

bertsmobile1 said:

Needing to pull the choke on to get clean running indicates a lean fuel situation in the engine.
This can be an air leak anywhere after the emulsion tube ( brass tube which sticks up in the carb.)
A low float level in the carb
Insufficient fuel supply to the carb.

If this is still happening the engine running lean will generate way too much heat for it to dissipate and that can cause it to be very difficult to restart but usually pulling the choke on full alleviates this situation.
Note it does not fix the problem , just works around it.

However I will wait for the spark test first.
The important thing is you only change 1 thing at a time or every one ends up really confused.

Click to expand...

@bertsmobile1 = I appreciate your feedback. I will start with the inline spark tester and report my findings. Should I purchase two testers to see if each plug is receiving spark at the same time or will only one spark tester be required?

If the spark test comes show that I am getting spark to both cylinders when the engine is hot, we will move on to the next step.

If I needed to use the mower this weekend, would I be doing any long term damage by continuing to run the mower in a possible lean mixture situation?

If I have done my homework correctly you have the horizontally opposed twin.
These use a double ended coil and both plugs fire each revolution ( called wasted spark ),
You have a circuit from ground through one plug through the coil through the other plug to earth so if one plug fires, both fire.
If one plug does not fire then neither fire so 1 spark tester is enough.

@bertsmobile1 = You are correct, I do have a horizontally opposed twin. One inline spark tester it is! I appreciate the follow up.

Sounds like you have some moisture in the carburetor. Drain and clean the carb bowl, and also check the fuel tank. Gas floats on water, so the engine will start and run from the gas on top. When the water/gas is agitated, the water maybe gets sucked into the carb and it won't start until the mixture sits and separates again. This is just a guess, but sounds reasonable.

buddha0360 said:

Sounds like you have some moisture in the carburetor. Drain and clean the carb bowl, and also check the fuel tank. Gas floats on water, so the engine will start and run from the gas on top. When the water/gas is agitated, the water maybe gets sucked into the carb and it won't start until the mixture sits and separates again. This is just a guess, but sounds reasonable.

Click to expand...

The mistake that most people make is that they think gas is drawn from the top. It is not it is sucked up from the bottom of the carb bowl and the bottom of the gas tank as well. It does not hurt to clean out the carb.

BlazNT said:

The mistake that most people make is that they think gas is drawn from the top. It is not it is sucked up from the bottom of the carb bowl and the bottom of the gas tank as well. It does not hurt to clean out the carb.

Click to expand...

Only on new carbs with a shut off solenoid.
Older ones draw the low speed idle from higher up in the float bowl because of the reduced lift of the smaller volume of slower moving air.
So you are both right & wrong.
Very common for pull start motors to start quite fine with a bowl full of water and die the instant you throttle on.
Not so common with ride ons.

bertsmobile1 said:

Only on new carbs with a shut off solenoid.
Older ones draw the low speed idle from higher up in the float bowl because of the reduced lift of the smaller volume of slower moving air.
So you are both right & wrong.
Very common for pull start motors to start quite fine with a bowl full of water and die the instant you throttle on.
Not so common with ride ons.

Click to expand...

And yes that is why you have to clean all the little holes in the carb when it is not running right.

I had same problem with my Kohler 26HP. Started fine when cool and would run all day until I killed the engine. Would not restart hot but would run all day hot. Bertsmobile1 cured my problem. He said my ignition modules were bad and he was correct.

Just an update. I was unable to grab the inline spark tester this weekend due to being out of town. I will update as soon as the rain stops here and I can get outside and mow!

After checking spark, coil, and fuel as you other mechanics suggested, I would run a
compression check first cold, then after it gets hot to compare. Could be the
valves have enough clearance when cold to start. But when heated up, they lose
clearance and come off their seats and not enough compression to start until
they cool down and the valve clearance returns and the valves return to their
seats.

I had an MTD for about 20 years with a Briggs and Stratton that did that. I just had to keep it running the whole mow, it had a parking brake thank god. after awhile I had too adjust the choke and throttle at the same time to keep it running with the PTO / mower engaged. I have no idea what caused this, I bought a huge starter, giant battery cables and threw in some hardcore 30HD. cleaned plugs filters etc. It ran, not much better than before, but then I tightened the choke and throttle with bicycle brake wire and it ran much better.

I have a Poulan chainsaw that starts once in a while and if stopped will not start
I have no clue. It has a lot of use though. SO DO AS I DO: FILL WHILE IT IS RUNNING OR TAKE TO A DEALERSHIP.
either way it's $$

bertsmobile1 said:

Needing to pull the choke on to get clean running indicates a lean fuel situation in the engine.
This can be an air leak anywhere after the emulsion tube ( brass tube which sticks up in the carb.)
A low float level in the carb
Insufficient fuel supply to the carb.

If this is still happening the engine running lean will generate way too much heat for it to dissipate and that can cause it to be very difficult to restart but usually pulling the choke on full alleviates this situation.
Note it does not fix the problem , just works around it.

However I will wait for the spark test first.
The important thing is you only change 1 thing at a time or every one ends up really confused.

Click to expand...

@bertsmoubile1 - Sorry for the extremely long delay getting back to you with my testing results. I was able to do some testing this weekend and I do have spark once I turn the motor off. I have noticed over the past two times mowing, that the choke issue I was experiencing before has gone away and now I can run the motor at full speed without having the choke pulled out a little bit.

Waiting for your next suggestion.

Thank you

Craftsman46

bertsmobile1 said:

And to pick your memory, does the mower exhibit any other problems when running?
If you do not turn it off, does it stop all by itself ?

Click to expand...

@ BertsMobile1 I have one more update. I have noticed over the past two weekends if I attempt to start the mower after it has been running, the motor will backfire but never turn over. In my research I thought I read once that this could be a sign of a flooded or malfunctioning needle in the carb.

I hope this extra information helps.