Cub trans that the gears clash when shifting.. what can be done?

[69ranger]

So after yesterday's success with the China carb fix... Thanks again Don!
I played with both cubs, and the 130, until way past dark. I started them and drove them around. Neighbors must think I am nuts, but It had been a while, since this stuff was out, and I was like a kid playing with his toys. I was on a roll with Red Tractors yesterday, and last night, was a good night in the I-H barn.

So now there is another small problem that I have always had with this Cub.. I guess it is more of an aggravation than a problem.
When I put in into gear the after its been sitting at idle the gears clash a little bit. This seems to go away, or be less noticeable at idle speeds than when the engine is running faster. Also if you press and hold the clutch down for 15 or 20 seconds, before shifting, it goes in with no clash.

So here is the History on this Cub. The clutch disk, and release bearing were both new, 5 or 6 years ago.
Dad and I changed then both out and the pressure plate fingers set to the proper height and adjusted with a dial indicator for run out.
The clutch is smooth as glass, and works as it should, so I think that is right. Trans is quiet, or as quiet as any of the 8 or 10 different cubs that I have been around. I just have the aggravating gear clash when going into gear, and I would like to make it go away.

So is this caused by wear in the trans, and the gears just coasting, or is their something deeper that may be troubling this thing?
Also new gear oil in the trans and the finals, when I had all that stuff apart and changed the brakes and all the final drive seals.
Like I said this is more of an aggravation to me than a problem. It just bugs me, since the other cub I have does not do this..

Thank in advance.
Brad

[Gary S.]

I have the same minor problem especially when it's really cold on the '49 Cub. By reading threads on here I suspect the pilot bushing in the end of the crankshaft- when driven into place it mushrooms out and then "drags". The fix is it should be reamed to either the proper clearance or at least checked after install.

[Waif]

IF your experiencing what I get...Plan on "run on" after you depress and hold the clutch. Your transmission shaft is coasting a while before it quits turning. As mentioned , it could be a snug pilot bushing. Some owners have managed to get spray lube to track into it with the tractor parked downslope. The time to work it is during replacement. By checking internal diameter...

Same grind cause can be expected with the P.T.O. trying to engage it. Just let it (trans. shaft from engine) coast to a stop.

You could double check your shifter where it meshes with gears. Just in case it's not your trans. shaft overrunning.

[Eugene]

If you press and hold the clutch down for 15 or 20 seconds, before shifting, it goes in with no clash.

Normal.

Stopped tractor, I wait the count of 5 seconds after depressing the clutch before shifiting gears. Your tractor may need a higher count.

[69ranger]

Thanks for the info. I did also replace that bearing. Never really thought to check it for size, just assuming it would be correct.
Dang, that means to cure this I will have to split it again. Well thats another project.

[Don McCombs]

Did you give the pilot bushing a shot of grease after installation? I would try Waif's suggestion first, before you split again.

[ricky racer]

Nobody mentioned greasing the TOB, not that greasing it will end the problem but it sure can't hurt. The TOB should be greased a couple times a year.

Most all Cubs have that issue to some extent. I typically disengage the clutch and wait a few seconds before pulling the shift lever into gear. A lot of times I can hear the gears in the tranny slowing down so I know when to put it in gear.

[69ranger]

Thanks again for the responses.

TO answer a couple of questions and update you on what I have done.

I suspect that the bushing is probably too tight. I see in my notes that it was for sure replaced, and I am sure it was not reamed to resize it, as I did now know that was necessary until yesterday.
I took the top off the trans and looked in on things, and it appears that the shaft is running after the clutch is depressed, and no matter how long you hold it down it continues to do so to some extent.

I probably did some thing stupid, but I checked my grease level, and it was ok, so drained about a 1/4 of grease out and replaced it with some double 0 0 gear lube. I had some around for an old snapper mower. This about the same as corn head grease, and since I never run the tractor in the winter time, my hope is that it will stiffen up the grease and maybe help keep the shaft from spinning so freely.
Also, I did grease the release bearing, as it has been a while since it was done. It has not ran very many hours, but its been 4 or 5 years ago, since it was all put back together. I usually grease the one on the work cub, a couple times during the mowing season.
Well thats the latest, and it seems better. It will bug me if I dont look in on it further, so I will probably split the tractor one of these days and do thing right. I have to take the hood and gas tank off any way, to fix the leaking hydraulic unit. Probably will get a kit and rebuild the touch control.
Thing will never really work again, as long as I have it, but I want it to be right.

[Matt Kirsch]

I'd be more concerned if it never stopped spinning. If it stops spinning in a reasonable amount of time, I would not fix what is not broken. It will get better with time and use, and if it doesn't then go ahead and split it.

[Glen]

Hi,
Below is a page from the Cub and LoBoy service manual, showing the running clearance for the clutch shaft in the pilot bushing, at Spline and clutch shaft.

http://www.farmallcub.info/manuals/gss- ... 005-02.jpg

Member tst on here repairs lots of Cubs, he has said the pilot bushing ID should always be checked after replacing the bushing. Some of them shrink after being driven in the crankshaft hole, and are too tight on the clutch shaft, making it keep turning when you press the clutch pedal down.

Ream the new bushing so it has the clearance shown in the manual.

They have said on here use cheap grease to grease the throwout bearing, so the oil in the grease will adsorb into the graphite material of the bearing.
If you used better grease, they have said buy cheap grease, and pump it in the bearing, and flush out the better grease.
The grease will come out the small hole at the top of the bearing, as you pump grease in the grease fitting, if the bearing has the hole.
You can use a grease gun just for the cheap grease, if you have more then 1 grease gun.