Farmall cub - grinding gears hunting engine

Hey all -

I became an owner of a '52 Cub about a year ago. We've done a lot of work to it and it's been a fun little tractor. I found a snow plow for it and have been having fun in the snow (though a set of chains are being sought).

Since I've had it, nearly every time I shift gears, they grind some. Something in there is not fully stopping when the clutch is pressed. Am I just not waiting for things to slow down inside of the gear box before shifting? Oil was changed and replaced with 85-90 gear oil and filled to the "full" side drain plug.

Any clue to what is going on here?

Also....as the engine is settling into a load (as in getting up to speed in 3rd gear), the engine lops 3-5 times, then settles out. Once the load is established, it settles out. Any place I should start diagnosing ?

Thanx all !

Pete

On the clutch here is the ..know all end all.. test to know if it fully releasing. With tractor warmed up probably at least 10 to 15 minutes operating in colder temps with the engine at idle put transmission in gear. Pull it back in neutral while continuing to hold the clutch pedal down, count 1001, 1002 then try to put it back in gear. If it goes in gear with no or minimal grinding as in maybe just a couple teeth clashing against each other it is releasing properly. If not and you get the ..buurack.. sound the clutch is dragging due to insufficient release or the pilot bearing..bushing is dragging. On the hunting there is a buffer spring on the governor that can probably be adjusted to cure that. Unfortunately I cant tell you the procedure for that. Maybe someone else will chime in to direct you.

Concerning the hunting, make sure the linkage between the carb and governor arm is correct. If I remember correctly push the throttle wide open which pulls the yoke back on the carb side. Remove the pin and pull carb arm all the way back and adjust clevis until the pin goes back in. Once done if still a problem there is a spring either on the front of the governor cover or the bottom (can't remember for sure) that needs adjusting. Should be a cap over it and inside a bolt with a screw driver slot for adjustment. Its quite possible the spring is broke so take out the bolt and see if the spring is broke or possible stuck. New springs are available. Put it back together and screw in until hunting stops. On my tractors it screws in most of the way. If you screw it in too far it will affect idle speed. You can probably google the adjustment procedures to make sure I have my directions right as the subject has come up quite a bit.

Try "Double Clutching" to eliminate grinding.

Nothing appears unusual here. The transmission is completely without synchronization. Anytime you try to make a moving shift the gears will grind. To double clutch you need a foot accelerator and I never heard of anyone doing that. The only time you need to shift on the move would be when shifting into high gear while on the move. Choose your poison, either you ride the clutch to start from a dead still in high gear or you shift on the move and the gears will grind. My dad (and I am 71 years old) had us shift on the move and it always would grind the gears. When shifting from a forward gear to a reverse or from reverse to forward make sure the tractor is completely stopped before you shift out of gear and it will stop most of the grinding. If the transmission oil is thick and cold it will need to warm up before the oil will stop spinning up the idle gears when you are stopped. If the transmission is spinning and the clutch is depressed put it into high gear first to stop the free wheeling gears. If the tractor is not moving it should go into any gear without grinding. If you have any type of PTO attachment that tends to free wheel, you will need to knock it out of PTO engagement to get the tractor into another gear. With experience you can get the PTO back into engagement while you are bringing the transmission back up to speed but you will grind the PTO engagement gear. Hope this helps.

Double clutching an M is easy, especially when down-shifting from 5th to 4th!