Kohler K321 Issue after rebuild.

[M i k e 33]

Ok this is probably going to be an easy one for the Kohler masters out there.  Just got my K321 (14hp) rebuilt with new piston, rod, rings, bearings, gaskets, etc.  Will only start with the choke full on.  Once it warms up I ease off the choke and it dies very quickly, like the ignition was shut off.  As long as the choke is full on, it actually runs really well, and sounds nice with no smoke.   I think I'll take the carb off and recheck things but have no idea what would cause this?

 

Thanks,

Mike

 

[wallfish 17,507]

That's a carb/fuel delivery issue. Starving for fuel or getting too much air from leaking throttle shaft and/or gasket.

Was the carb cleaned and rebuilt too?

If it has a high speed needle adjustment, adjust it. Usually the one right on top. The Kohler service manual will cover the full process of how to dial it in.

 

 

Kohler K-Series SM TP-2379 LR.pdf

Edited August 28, 2016 by wallfish

[Ed Kennell 40,513]

    Air leaking in around the carb.  Check the throttle shaft and the gasket and bolts.

[prondzy 3,883]

When you installed the fuel pump after rebuild did your place the fuel pump plunger lever on the topside of the camshaft (plunger will work) or did you accidently put the lever on the underside of the camshaft (plunger will not work)?

[pacer 3,176]

13 hours ago, prondzy said:

or did you accidently put the lever on the underside of the camshaft (plunger will not work)?

 

Oh Boy! I'm familiar with that one! MAJOR frustration............

[953 nut 57,994]

Is this the same carb that was on it prior to the engine rebuild, if so how did it run then?

[rmaynard 15,927]

I'm going to agree with all the above. You have a fuel problem. Whether it's carburetor or pump related, you are being starved for fuel. First test that I would do is to remove the hose going from the pump to the carburetor, crank over the engine and see how the flow is from the output side of the pump. If it is strong, then pull the carburetor. Check what was said in posts 2 & 3 above, and be sure that the main jet needle is clean on the inside (it's hollow with little holes in it).

[M i k e 33]

Hey thanks for the feedback guys.  To answer the questions, yes, it is the same carb that was on the engine from before.  It was itself rebuilt several years prior to the engine rebuild.  The engine ran fine with no air/fuel related issues.  The carbs adjusting screws were not moved before, during, after the engine rebuild.   The fuel pump is the same one that was on the engine from before.  It has not been opened up or tampered with in any way.  I don't believe the fuel pump is installed incorrectly as the engine runs very well even at higher RPM in its current state, just must have the choke full on.  My understanding is that if its not installed properly it wouldn't run at all, or extremely poor?   

 

Have another carb rebuild kit, will probably try that since the engine sat for several years in my garage without being ran.  Perhaps the gaskets dried out?  Let me know.

 

Thanks,

Mike

[953 nut 57,994]

1 hour ago, M i k e said:

Perhaps the gaskets dried out?

Or perhaps a little critter crawled inside and built a nest. amazing what a mess a small spider can make; I now bag up small parts being stored.

[prondzy 3,883]

18 hours ago, M i k e said:

  I don't believe the fuel pump is installed incorrectly as the engine runs very well even at higher RPM in its current state, just must have the choke full on.  My understanding is that if its not installed properly it wouldn't run at all, or extremely poor?   

 

 

Thanks,

Mike

Beleiving an checking/knowing are two different things,  and isn't the issue you described above considered poorly if you have to run it with the choke on? Your starving of fuel and the only way to get the fuel into the carb is by drawing a strong vacuum with the choke plate closed. It's not impossible but if you didn't do anything to the carb it's probably not the carb, check the fuel tank, fuel lines, filter, and the fuel pump first.