My carbinator...yeah right...

[zedhed]

Well guyz, got the kohler courage running in my simplicity 16gth and mowed my place just fine. Except for every once in a while it would kinda sputter and seem to loose power. So I started to mow again this weekend and pretty quickly lost power and sputtering. So I got to looking around and messing with it. Even idle-all the way to the slow throttle stop, just a little bit of back firing. This also happens at full throttle and mid throttle. Well as soon as I pulled the aircleaner I saw that I have a little tiny bit a gas "blowing" back out of the carb intake. Kind of a mist, but you can see the droplets of fuel. So per the manual I checked the float setting, and it is per the manual. So I blew out the needle seat and put it all back together but no change. So can anybody tell me what to do from here? Btw, brand new engine, brand new carb, brand new fuel filter. And thanks in advance.

[UCD]

If it was a car engine I would say valve timeing is off

[zedhed]

Yeah Ive been thinking bout this a little bit. Where the carb and aircleaner come together there should be only suction. (I think anyway) So how come gas is being blown back out of the carb? Could this possibly be a blown head gasket? Whatcha think guyz? Oh yeah sometin else to relate to yall, when I get the power loss the motor makes a chugging sound. It goes from its steady normal engine sound to a chugging or chuffing sound and just a little bit of backfire.

[D-17_Dave]

I agree with Maynard that with the spitting gas back out the carb it acts like the cam is off a tooth, but there could be some exhaust blockage somewhere. Might try pulling the muffler and checking for a mouse nest or other forien material.

[Tiny]

You might have a problem with the carb adjustment. Locate the high speed jet and then throttle it up to max then turn the jet screw in and out to where it starts loosing power in either direction and then set it in the middle of those 2 places. I think it's the same exact scenario with the low speed adjustment only do it at idle.

[PatRarick]

I would check the valve clearance first. Sounds like an intake valve is set a little too close. Clearance decreases as the engine warms up. Pat

[UCD]

It is a valve adjustment or a valve timing problem. You have an intake valve or intake valves partially open during part of the compression stroke. This pushes air back out the intake valve, runners and carb. One cylinder trying to suck in gas and the other is blowing it out. The air pressure out over comes the vacuum in and blows gas out the carb there by starving the cylinder. on the intake stroke of fuel This can be caused by valve timing or by a sticking valve or as Pat states valve clearance by the valve stem getting hot and expanding causing the intake valve to stay slightly open after the engine gets hot There is more to it but that is about as simple as I can discribe it.

[zedhed]

Ok, I pulled the head and there does appear to be leakage around the intake valve. In all of the soot it looks like tracking and the intake vlave is all (sooty) black, as is the whole combustion chamber. Gonna pull the valve out for a better look, and check the valve seat etc. Then of course will reassemble and then check clearances. Thanks for all the good info, good team here.

[zedhed]

}:)and on we go... still having the same problem. once the engine heats up, say 10 to 20 minutes its just like someone pulled the choke on, and the throttle does nothing. since my last post i have reset the valves. they were at a tight .003 so i set em to a loose .003 so that the feeler guage would slip out under its own weight. (standard feeler gauge set) i guess im gonna have to build the manifold to do a leakdown test. cant do a typical compression test due to the compression release on the kohler single cylinder courage engines. any more thoughts, send em this way please.

[HubbardRA]

As Maynard said above, you should remove the valve and check to see if there is a varnish buildup on the stem of the valve. I had a car that did that. An intake valve stuck open, and the 6 cylinder engine would barely pull the car on level ground and had no throttle response. I cleaned all of the valve stems, put on new valve seals, and it ran fine.

[MrSteele]

.003?? I am not a plumbing fixture fan, but that sounds way too close. The expansion of the valve as the engine warms would close a gap that close easily on most engines, and I assume that Kohler is among "most". I'd check the stem, too, for varnish buildup, then open the clearance to no less than .010, just because, and that may still be too close.

[zedhed]

ok, not a problem, can do, will do and get back to you all with the results. Thanks!

[zedhed]

And on we go... UH... when I installed the new motor, I left the original fuel filter on the tractor, the motor came with one installed. Last night I was looking at the one on the motor, and noticed that it wasnt getting even half full when the tractro was (trying)to run. So I replaced the one that was originally on the tractor, and HEY the filter on the motor filled right up and the motor ran like it should. This weekend I will actually attempt to mow with it. Hoping that was the prob and hoping for the best.