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Discussion Starter #1
Good morning - I've been reading alot of posts on here and they've helped me get a handle on what might be wrong with my snapper mower. Unfortunately, the problem is still happening (with some improvements)

I got the mower used and was told it hadn't been used in over a year. So first thing I did was to try and figure out it's condition. I cleaned the exterior, checked the plug & oil - everything seemed OK (except the battery was dead, but I expected that). I put some gas in that I'd been using on my Honda all summer, and tried to pull start it. Almost immediately I noticed gas dripping out of the carb bowl. So I took out the gas line, and figured it was probably stuck ...tapped it lightly with a wrench ...dripping stopped. I gave it a pull and it started right up (with a big cloud from the excess gas). I ran it for a minute or 2 and everything seemed fine. Shut it down.

The next day I go to mow the lawn and it starts right up ....but then after like 2-3 minutes it starts to sputter then dies. I noticed the carb was filled with gas. So I opened it up, the float seems fine, the needle valve holds air pressure, the carb itself seems fine. I did notice the gasket around the bowl was deteriorated - so I figured some flakes of rubber had held the need vlalve open or something ...sprayed it a few times with carb cleaner, replaced the gasket & the main jet, replaced the spark plug just to be safe, new fuel filter, treated the gas a little (just in case) with seafoam. re-assembled it, gave it a pull. It started right up, ran great - responded to throttle real well. ....For about 2 minutes.

Then it started to sputter again. shut it off. Restarted it...rough start and idle. Once it sits and cools for a few minutes it's fine. I checked the air intake - no noticable gas anymore ... but it could be the carb again, I guess.

It seems to start sputtering once it runs for a few minutes (once it warms up). It's got an old warbol(?) carb without the solenoid. Should I reclean (more thoroughly) the carb? Any other ideas ?

appreciate any help,

- Bill
 

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Check the gas cap and make sure the vent has not plugged up. Dirt, critters, etc... can plug that up creating a vacuum in the fuel tank.

Test by loosening the cap all most all the way and then test the mower.

I'm assuming the gas overflow issue has definitely been solved.

-Larry
 

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Discussion Starter #3
I've actually taken the gas cap completely off just in case- same thing.

As far as the gas overflow issue - I think it has been solved. By that I mean... before it filled the air intake right as it died - you could see the gas with the air filter off. ...Now, I've never let it die all the way since I 'cleaned' the carb...as soon as the sputtering gets intense I turn it off. And there's no gas in the air intake (which doesn't mean there might not be some in the carb ...it's just not overflowing all the way up into the air intake) If I let it sputter til it quits, it might ..but I haven't tried that since the carb work was done. So I think it's solved - but that might still be the issue, actually

Thanks for the reply, BTW ....
 

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Discussion Starter #4 (Edited)
Another note - I did check the needle valve against air pressure with just gravity holding float down (upside down) and it seemed to seal and hold just fine ...could heat affect the way that needle valve seals ?
 

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I'm afraid I'm stumped at this point :)

However I do remember someone mentioning somewhere that sometimes when coils go bad they will work for a few min, then fail when the engine warms up?


-larry
 

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It sounds like a carburetor problem to me, I would make sure it is completely clean, especially the the air bleed and bowl vent, inspect the inlet (float) needle and seat and replace if worn. While you have the carburetor off I would also check valve lash, these engines have a tendency to to stretch the intake valve stem and loose clearance, allowing blow by back into carburetor and can make engine sputter.
 

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Discussion Starter #9
I think you might be right, about the carb (I'm hoping that's all it is). I'll definitley re-clean it, thanks.
I don't know where the bowl vent is on these models though - is it in the bottom mounting bolt? I don't remember seeing a vent hole in it ....
oh ...and how do I check the intake valve stem - just make sure it's still flush and not pulled up?

Thanks a bunch
 

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I believe that carburetor is internally vented, look for a little hole just inside the throat of the carburetor that opens up into the top of the carburetor, should be clean and allow air to flow into and out of carburetor.

Just behind the carburetor on the side of the engine block you should see a plate with two small cap head screws holding it on, also comming out of this plate is a rubber hose (oil breather) that attaches to the carburetor. This is the oil breather, remove the two screws and take the breather out taking care not to tear gasket. With the piston at TDC on the compression stroke, using a feeler guage check the clearance between the the valves and the lifters.
 

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Discussion Starter #11
Yes, I know the vent you mean now....

Oh .. the oil breather ...I see what you're talking about yes I recall it was a little floppy...do you off- hand know the clearance gap it should be at TDC?
 

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I agree with 30yeartech something in the carb is the problem
Check that there isn't some crud in the gas tank or filter.
Bowl gasket maybe braking up also.
 

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Discussion Starter #15
Well, It appears to be fixed (ran for over 30 minutes with very little if any sputtering). I did reclean the carb (although everything looked OK). I did notice some oil residue in the air vent (and on the spark plug) - and thought I'd better check the oil. Well, it was way too high in level and when I emptied it -it was like tea ...totally liquid. So I changed the oil. It was probably a combination of both the carb and the fouled oil.

Thanks for the help guys !!
 

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I don't know how we all missed it, but you said the carburetor was leaking when you got it. A flooding carburetor will fill with gas and then the fuel will flow into the cylinder and eventually the crankcase. You had gas mixed in with your oil and when you would start running the engine it would eventually come out of the breather and into the carburetor causing a "rich" running condition (sputtering).

Make sure the carburetor does not leak anymore when it is just parked and not being used. Check the oil level before use and if it has increased, drain it and change it.
 
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