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Intek 12.5HP cranking but not starting fuel coming out exhaust manifold gasket the bolts holding the exhaust manifold on are tight. could a blown manifold gasket prevent ignition?
The carb was run dry as I do whenever done mowing , I drained the old fuel inside take.

The engine turns over my battery has 12.25VDC. 1st I noticed fuel dripping from the bottom of the carbs bowl then I noticed fuel coming out the exhaust manifold gasket which was actuely wanting to start a fire, this is when I stopped trying to start her.

I have a spark tester but not sure if it can be sean during daylight I didn’t see any lighting. When I saw the redness of the fire right at the exhaust manifold gasket I figured shes getting spark.

I always start w/ the choke on,Of course last year spark plug got gas fouled now the brand new spark plug is also gas fouled.

This usley happens every lawn season at first mow I have been getting away w/ just swapping the Spark plug champion RC12YC spark plug but not now. w/ spark plug removed trying to start I see fuel coming out SP hole.Thanks for any advise.
Additionally I replaced the engine 5 years ago w/ same intex 12.5HP been running good probably could use a valve adjustment I just haven’t gotton the hang of adjusting the valves.

2007 Snapper RER.









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update: there wasn't a exhaust manifold gasket, the manifold itself was cracked.


could this prevent ignition bc most of fuel in the cylinder was being pushed out?

luckiely I saved the old engine so I swapped the old manie on. guess I'll buy another spark plug an try again.thanks for advising

Looks like an old school Snapper. I have a mid 80's model.

Replace the float needle in the carburetor. Option 2 would be to replace the carburetor. A cracked exhaust will not cause this starting issue, but fuel left in the machine all Winter will. The tank has to be emptied at the end of the season and only new fuel used when you get ready for the next season. No stored fuel keeps more than a month or two regardless of miracle additives (snake oil).

Could it be possible that the engine was flooded by continuing to crank it with the choke fully engaged? Did you pull the plug and see if it was soaked with gas? Is your oil level okay? Did you store it without fuel stabilizer? As Auto Doc's mentioned, the needle valve in the carb could be stuck open...you can try rapping lightly on the bottom of the carb with a wrench, which may work to get it to seal, or you may need to remove and clean the carb. Steps I recommend: Replace the spark plug: Drain any stale fuel from the tank and clean the carb; after those steps are done, please let us know if it helped. I would have that exhaust welded before it completely fails.

fuel should never drip out of the bowl even if you crank for hours unless there is something wrong with the seat, needle or it is the kind of carb that has gaskets between sections that help contain the fuel and they went bad.

sgkent said:

fuel should never drip out of the bowl even if you crank for hours unless there is something wrong with the seat, needle or it is the kind of carb that has gaskets between sections that help contain the fuel and they went bad.

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I believe he said it was blowing fuel out the exhaust rather than the carburetor. Respectfully. Kevin.

Bottom line, fix carb needle/seat.
Do NOT try running it with fuel diluted oil.
Dump oil and filter if it has one. New SAE 30w to the full mark.

Pull the carb off. See if fuel is running out of the carb throat. Float, needle and seat should seal off like a toilet. Inverted carb body/needle/seat needs pressure tested at 7PSI for 30 mins.

slomo said:

Bottom line, fix carb needle/seat.
Do NOT try running it with fuel diluted oil.
Dump oil and filter if it has one. New SAE 30w to the full mark.

Pull the carb off. See if fuel is running out of the carb throat. Float, needle and seat should seal off like a toilet. Inverted carb body/needle/seat needs pressure tested at 7PSI for 30 mins.

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Alternately, with the carb off the engine, remove the bowl and let it dry of gas. Invert the carburetor and use your mouth to create pressure by applying a "pucker" technique. Then, place your tongue over the inlet to see if it holds pressure.

kbowley said:

Alternately, with the carb off the engine, remove the bowl and let it dry of gas. Invert the carburetor and use your mouth to create pressure by applying a "pucker" technique. Then, place your tongue over the inlet to see if it holds pressure.

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I will bet it is a Nikki carburetor. Add fuel shut off valve. Read and use the above information.

I don't know why every DYIer thinks a fuel shut is a cure all for leaky carbs. They should learn how to cure the real problem. I have many tech to bitch about the Nikki single barrel carbs being hard to repair when it is not when you know what you are doing. Most fuel leakage with Nikki carbs is just the fuel bowl gasket set needing to be replaced. Yes the spaghetti gasket is picky at times as it has to be nearly prefect. Otherwords no defects or it will leak.

And not all of us have a set lungs (I know I don't) that can develop the pressure needed to test these or are able hold the pressure long to actual see a leakage. Beside putting your mouth on as filthy as engine parts isn't very safe but of some people will let their pet cat lick them in the mouth after it been licking it anus and privates yet they are worried about germs.

Personally I have found a pressure/vac tester the best to test the carbs for pressure leaks. And even these test a rare time you could have a carb to pass minute and fail the next test. I just had old Tecumseh carb that had random needle seat problem. One time it would hold and the next time would not. Finally end up having to replace the carb to resolve the leakage problem. New rubber seat and needle valve would not solve the problem. And before someone ask I did make sure installed the seat correctly.

And Btw that crack muffler flange needs to be welded up. I have seen them to cause the cylinder head to over heat and loose a valve guide.

1st I noticed fuel dripping from the bottom of the carbs bowl then I noticed fuel coming out the exhaust manifold gasket

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again, fuel should never drip from the bottom of the carb's bowl. It means that the needle is not sealing, or if one has the two piece float area, that many section gasket may be bad. If the engine is so rich that fuel is dripping off it, it will not start. Drain the oil, rebuild the carb and start over. If that feels uncomfortable, take it to a reputable shop who can.

Notice the many section gasket, and the plastic bottom next to the float in the photo. If it is this type carb, the seat or that many section gasket in the center of the photo can be bad and leaking. Picture is from Amazon.

StarTech said:

some people will let their pet cat lick them in the mouth after it been licking it anus and privates yet they are worried about germs.

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Go StarTech, go StarTech............. Love it.

I tried rebuilding a Nikki with OEM Briggs parts. I failed at it. Bought a Chinese clone of the Briggs single cyl Walbro. Ran like a top.

slomo said:

I tried rebuilding a Nikki with OEM Briggs parts. I failed at it. Bought a Chinese clone of the Briggs single cyl Walbro. Ran like a top.

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You can buy the o-ring kits for Nikki carburetors in 5 packs.

StarTech said:

I don't know why every DYIer thinks a fuel shut is a cure all for leaky carbs. They should learn how to cure the real problem. I have many tech to bitch about the Nikki single barrel carbs being hard to repair when it is not when you know what you are doing. Most fuel leakage with Nikki carbs is just the fuel bowl gasket set needing to be replaced. Yes the spaghetti gasket is picky at times as it has to be nearly prefect. Otherwords no defects or it will leak.

And not all of us have a set lungs (I know I don't) that can develop the pressure needed to test these or are able hold the pressure long to actual see a leakage. Beside putting your mouth on as filthy as engine parts isn't very safe but of some people will let their pet cat lick them in the mouth after it been licking it anus and privates yet they are worried about germs.

Personally I have found a pressure/vac tester the best to test the carbs for pressure leaks. And even these test a rare time you could have a carb to pass minute and fail the next test. I just had old Tecumseh carb that had random needle seat problem. One time it would hold and the next time would not. Finally end up having to replace the carb to resolve the leakage problem. New rubber seat and needle valve would not solve the problem. And before someone ask I did make sure installed the seat correctly.

Click to expand...

I see very few fuel shut off valves on equipment that comes in my shop for the first time. I install them mainly so the customer can run the fuel mostly out of carburetor so it won’t gum up, and need to be cleaned after storage. Which is why they often come to me in the first place, because the carburetor is dirty.

Tiger Small Engine said:

I see very few fuel shut off valves on equipment that comes in my shop for the first time. I install them mainly so the customer can run the fuel mostly out of carburetor so it won’t gum up, and need to be cleaned after storage. Which is why they often come to me in the first place, because the carburetor is dirty.

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I install on every mower possible. And a crappy filter if there is room on the line. Got to get drastic with all these fuel related issues.

slomo said:

I install on every mower possible. And a crappy filter if there is room on the line. Got to get drastic with all these fuel related issues.

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I think a lot of shops don’t install fuel shut off valves so the customer has to bring it back in to have another carburetor installed or cleaned in the future.