Caught fire now smoking

So you are saying that the fuel shut off valve isn't sufficient to stop fuel from leaking by, I did replace the gaskets in the carb, I assumed it was the float leaking past .

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The float is going to leak anytime fuel is reaching it. If the engine is off, it fills the cylinder(s) and drips down into the crankcase. If the engine is running the excess is going to get pulled into the cylinder and burned. The excess will make the mixture rich, which will be washing down the cylinder walls making for metal on metal contact with no oil protection. Just because it is running will not make the float behave. The float is going to constantly overfill the bowl regardless whether it is running or not.

Make sure the fuel tank cap is venting, because if it gets plugged then the fuel in the tank expands when it warms up, and that can push the needle off the seat.

jlwoods99 said:

The day I originally fueled it up and got it running, when I was done shut it down, it backfired when I shut it down, so I'm assuming it is still sticking. Any good ways you recommend cleaning the carb? Someone mentioned a ultrasonic cleaner? Also what is your thoughts on reassembly, do I need to set the clearance on the rocker arms, I was surprised how sloppy the were when the valves were closed.

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If you do not have a service manual search on-line for how to set the valve lash at .003-.005. (and sometimes on some older engines the valve lash will change again after the engine is operated awhile requiring a adjustment for a 2nd time. (so do not be surprised if you have to do such) Adjustment of the Intake valve is the critical one so as to get a compression release. I try to set it at .003.
Also you will find it's usually best to install a carb kit into old Nikki carbs before you put them back together replacing ALL the gaskets and o-rings.
I just do away with the anti backfire valve (ABV) on my eq if it starts giving trouble and YES it does not prevent flooding. It's to prevent (reduce chance) backfire when you kill the engine.
A in-line fuel filter is also a good thing.

The fuel solenoid does not stop fuel from leaking into the crankcase.
It's a antiback fire solenoid. Just let the engine idle for awhile before killing.
It's not really needed. Some guys just cut off the plunger instead of spending big buck to replace something that is not needed.
Also it's best to pressure test that type Nikki carb by connecting to the input fuel barb and turn the carb upside down and see if it blocks 5 lbs of input pressure. If not gently hold down on the float or the needle. If still won't hold pressure it's the upper rubber gasket above the float leaking.

You need to put the engine together and start it up and see if the smoking has stopped.
Lots of oil has made it's way/dripped onto the muffler below the valve area.

You can get a replacement carb for that engine for less than $20

Appears corrosion has got the best of your carb.

Let us know what you find. Getting hard to keep up with 3 pages of posts. I may have mentioned something that's already been said.

On this engine the one is steel and the other is aluminum. This is normal and the reason the colors are different.

Forest#2 said:

The fuel solenoid does not stop fuel from leaking into the crankcase.
It's a antiback fire solenoid. Just let the engine idle for awhile before killing.
It's not really needed. Some guys just cut off the plunger instead of spending big buck to replace something that is not needed.
Also it's best to pressure test that type Nikki carb by connecting to the input fuel barb and turn the carb upside down and see if it blocks 5 lbs of input pressure. If not gently hold down on the float or the needle. If still won't hold pressure it's the upper rubber gasket above the float leaking.

You need to put the engine together and start it up and see if the smoking has stopped.
Lots of oil has made it's way/dripped onto the muffler below the valve area.

You can get a replacement carb for that engine for less than $20

Appears corrosion has got the best of your carb.

Let us know what you find. Getting hard to keep up with 3 pages of posts. I may have mentioned something that's already been said.

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Where can you get a replacement carb that cheap?

This is the Briggs parts manual for your model number. It shows a Nikki carb and Walbro. The Nikki carb is part 794572. I couldn't find the Walbro. People here have recommended replacing the Nikki with a Walbro, but I don't know the part number. Hopefully someone will speak up with that.

With the carb part number, Amazon has many inexpensive options, though it can be a crap shoot with Chinese replacements. I've had pretty good luck. Don't pick the cheapest, and pick something that has a decent number of reviews. My thought is to buy something that they've sold a bunch of. You can often find carbs in the $20 range. The other option is to go for OEM, though that may be Chinese too. Partstree.com, ereplacementparts.com, partstree.com and others are out there. Jack's Small Engines has been getting some bad reviews.

This shows 700 reviews, seems they've sold a few. https://www.amazon.com/Mckin-794572...sprefix=31c707-0603+carburetor,aps,212&sr=8-3

Mark H_NO said:

This is the Briggs parts manual for your model number. It shows a Nikki carb and Walbro. The Nikki carb is part 794572. I couldn't find the Walbro. People here have recommended replacing the Nikki with a Walbro, but I don't know the part number. Hopefully someone will speak up with that.

With the carb part number, Amazon has many inexpensive options, though it can be a crap shoot with Chinese replacements. I've had pretty good luck. Don't pick the cheapest, and pick something that has a decent number of reviews. My thought is to buy something that they've sold a bunch of. You can often find carbs in the $20 range. The other option is to go for OEM, though that may be Chinese too. Partstree.com, ereplacementparts.com, partstree.com and others are out there. Jack's Small Engines has been getting some bad reviews.

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Hello M.,

All carburetors are basically made by various overseas companies these days, some are just better than others.

I also suggest to pick the middle of the price range if given the choice. The best deal is not always the best part.

Not sure about what has been happening with Jacks small engine parts lately either.

I've had good luck with the clone carb's from HIPA on Amazon.
Most generally Amazon has a FREE return full refund also with a certain number of days so look for such. If it won't work ok and you think it's the carb just return..

You will find that the WALBRO carbs are NLA. If you try to use a Walbro carb part number you will be defaulted to a Nikki or Ruxing type carb making you think you are getting a Walbro, but it's a clone sub.

I keep couple of the NLA Walbro carbs around to test engines to see if the carb is a fix, if so I either rebuild a OEM NIKKI carb or buy a clone. When trying to find kits for a Nikki or pieces use Briggs as the part number instead of NIKKI.
Also the Nikki have at least two different kits, one for a steel bowl and other if for aluminum bowl. You can find info for both on-line, You tube videos kitting. You will find once a Nikki is taken apart you will need a kit before going back together.

Sawzill.com has Briggs Nikki parts. A clone carb is not worth kitting usually.

Also a static governor adjust may be required to get the throttle correct when replacing a carb.

jlwoods99 said:

So 17.5 hp vertical shaft. I had a senior moment the head end caught fire for a minute or two, now when I start it ,it's burning oil something bad. I'm assuming valve seals or something? It will start run a few seconds then die, it'll restart. Like it's starving of gas. Also the smoking. Any thoughts. Please be kind.

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Yeah,
Not sure you want to start this thing until you first find out why it is catching on fire. The fact that it will not start could be a blessing