Blown Head Gasket on John Deere 140

[wilamayb]

I was mowing with my late model 140 with a Kohler K321. I noticed it started sounding funny. I raised the hood to see that oil was oozing out between the block and head (I also assume compression also under load is what I was hearing). This thing has eaten about 4 head gaskets in the last 15 years. The head has been replaced in an attempt to get a flat one, which did not cure the problem obviously.

Does anyone else have this problem? What gives? Engine does not run hot or lean. Even puffs a little black smoke under acceleration.
 

[wisbaker]

I had a lot of head gasket issues with K181s on Toro sand pros and on K321s on trucksters but never any problem with 321s on a greensmower III. I always associated the sand pros and trucksters head gasket problems because they got lugged a lot, that is full throttle but loaded so much they ran less than 3600 rpms. To fix clean and check the head and block deck for straightness, check all your bolts & studs make sure none are stretched and all threads (male and female) are clean- run a tap or die on them. Torque the head gasket in three steps using the Kohler manual for pattern/sequence. This was back in the days of leaded gas and Kohlers had a habit of building up hard carbon deposits in the combustion chamber, if you didn't get all the carbon off the block they didn't seal well, if you didn't get it off the top of the cylinder wall it would build up until it broke the top ring on the piston. I was pulling heads and cleaning combustion chambers every 200 hours of use, with that care they were a 3000+ hour motor.
 

[Roger in Iowa]

Recently bought a 314 that ran rough. Found it had a failing head gasket. Replaced gasket and still ran terrible. Found points set at over 0.30 which made the timing too fast. Set the points at 0.18 and runs well.
 

[Roger in Iowa]

Correction: points set at 0.30 would make timing slow (retarded).