Kohler Courage got me stumped

[fordie]

I have a Troybuilt Bronco with a 20hp Kohler engine. I bought it used, about one year old but used sparingly by original owner. It worked fine summer before last during the final month or so of mowing season. I bought a new zero turn this past summer and only used the Troybuilt for hauling my lawn trailer around and some rough area mowing. Mid summer it began to hesitate during startup, like the starter was hanging up. In fact, I would sometimes tap the starter lightly and it would turn over and start. I decided that this winter I would service the mower and replace the starter. Since the original battery was weak I replaced it and since the solenoid was cheap, replaced it also. Bought and installed a new starter after those replacements and cleaning all grounds provided no improvement. Still had the same issue, turn to "compression" and stop. So after some research I removed the valve cover and checked clearances [.005 on intake and .007 on exhaust] also watched exhaust valve for slight bumb from compression release [it did]. While I had the plug out [by the way, it spins great with plug out] I looked for signs of carbon but found none. I am out of ideas, anyone have any insight to help me? Thanks.

 

[banjodunn]

G'day fordie I think you will find the comp release is not working fully I remember going to a school and they told us they were having probs with some of them ( plastic unit on the camshaft they had a mod for it) just can't remember which model it was and cannot put my hand on the relevant book at the moment. If I find the book I will let you know



Jon

 

[deerseeker001]

Welcome from Wisconsin

 

[fordie]

G'day fordie I think you will find the comp release is not working fully I remember going to a school and they told us they were having probs with some of them ( plastic unit on the camshaft they had a mod for it) just can't remember which model it was and cannot put my hand on the relevant book at the moment. If I find the book I will let you know



Jon

I assumed that if I could see the exhaust lift it would indicate the release was working. Not the case huh?

 

[fordie]

Can anyone tell me if the exhaust valve lifts slightly on intake stroke that would mean the compression release is functioning? Can it just not lift enough? I found a site that showed the correct position of the flywheel magnet at TDC and mine seems in the correct position which would rule out timing key problem. That seem correct?

 

[DSM123]

There was a series of that engine that had powdered iron flywheel ring gears. There was a Kohler service bulletin issued regarding this.
I had the same problem with a 26hp and it was a cracked ring gear which eventually failed and destroyed the starter. Approx $300 in parts to repair the thing.

http://www.lawnsite.com/showthread.php?t=373605

Unfortunately the link to the SB no longer works.

 

[fordie]

Ok, I will take a look. Thanks.

 

[dconine]

Change both of your battery cables. A lot of times they put undersized cables on those units and overtime they build up resistance, and in turn you will have voltage drops.

Pretty good chance that may cure your problem. If you can put slightly heavier cables on, I would go that route.

 

[David_Kb7uns]

Friend had shop at local farm store and a few years back they had a bunch of Home Depot mowers with problems on the Kohler Courage engines used on MTD made mowers with the compression release going bad. At the time the parts were back ordered over 60 days out. Turned me off at the Cub Cadet garden tractor was looking at and got the Kubota G2160-60 with the D782 engine.

David Kb7uns

 

[banjodunn]

G'day fordie the ex valve should crack open just before firing on comp stroke, sorry for the delay getting back to you still cannot find my books will have a look out at the farm on the w/end when I am out there.


Jon