G engine knock

[JLG]

My 1950 "G" has developed a knock. I've noticed it off and on for a little while, but today I plowed a little and it's definitly gotten worse. The only time I don't notice it is when the engine is at a slow idle. If I listen with a piece of hose, the knock is very obvious when you listen at the center of the flywheel. You don't hear it much at all if you listen in the crankcase breather ( meaning I assume it's not the rods). It almost seems like there's someone tapping under the operator platform with a ball peen hammer.

I've replaced the flywheel bolts, thinking maybe it was a loose flywheel. That hasn't seemed to help. Could it be in the clutch? Any other ideas? Am I going to have to mentally prepare myself to pull the crank this winter, because if thats the case I better start on that now, ha. Thanks.

 

[Anonymous-0]

could be a rist pin,seems worse sometimes than other times, because it turns????

 

[bdpuller]

Check the clutch driver or the crank end-play. Both will make you think something's very serious.

 

[sick48a]

My 48 A had a knock to it, ended up being the clutch bearing.

 

[Kurt_JDB]

Could be the first reduction gear is loose on the shaft. Pull the clutch pully and reach in and grab the first reduction gear and see if you can wiggle it around.

Kurt

 

[jd b puller]

A loose flywheel will drive you crazy. You'll swear it's inside the motor or even on the other side. Go get a pair of new bolts from Deere and see if that cures your problem.

 

[Resting Relics 1]

Hey jlg,
Had a 1949 A once that had a bad rod bearing and ruined the crank. It only knocked when under load.I had to have the crank welded and reground. It's not a big job to pull the crankcase cover and pull the rod caps just to be sure if other things like the flywheel and clutch don't show any obvious problems.
John