Rejoin 1950 Cub

[Old Man]

1st time I’ve split a Cub. I blocked the front and rolled the back away from the split. The split went fine and I replaced the rear main seal and entire clutch assembly with no problems. Attempting to rejoin the tractor.....not so good.
I am able to walk the back into place with the shaft aligned and get it to within 1 inch of the bell housing surfaces meeting and it stops there. I am even able to thread 7/16” x 3” bolts into the holes at the top of the housing by hand. Should the bell housing close tightly and then be bolted together or is it pulled together using the bolts?

[Glen]

Hi,
Usually the clutch housing will go onto the 2 dowel pins on the engine by hand.
If the pins are rusty, sand them with fine sandpaper, and clean them.

The clutch disc needs aligning as you put the clutch pressure plate on, or the spline in the disc will be out of place, and the Cub won't go together.

If you replaced the pilot bushing, it may be too small an ID after driving it in the crankshaft hole.
Some of the new bushings are too small an ID after installing them.

After installing one, the ID should be checked with a dial caliper, and the running clearance compared with the spec in the Cub service manual.
If you put it together without checking the ID, it may be too small, and the clutch shaft may not stop turning when you push the clutch pedal down. Then the gears grind.
I would take it apart again and check the pilot bushing ID, if you replaced it, and didn't check the ID after putting it in.
The bushing ID needs reaming to make it bigger, if it is too small.
tst has said they should be measured after installing them.

Below is the page from the Cub service manual with the running clearance spec at Spline and clutch shaft.

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

Turn the clutch shaft by hand when the Cub is split, and check that it runs straight, and is not bent.

Put a thin layer of grease on the end of the clutch shaft that goes in the pilot bushing, and a thin layer of grease inside the pilot bushing, before putting the Cub together.

[Dale Finch]

I know this sounds stupid, but are you sure the steering wheel isn't hitting the steering support? BTDT!

You probably already know, but you can engage the PTO allowing you to turn the drive shaft to help get the splines to line up.

Good luck!

[Stevetractor]

Try putting transmission in neutral and PTO in gear. Then by hand spin the PTO shaft to help align splines on clutch disk and driveshaft. They can be a pain sometimes if you don’t have an old shaft or alignment tool to center disk. Just be patient. Good luck.

[Stevetractor]

Your faster at typing than me Dale Shaw.

[Dale Finch]

Your faster at typing than me Dale Shaw.

FYI...the OTHER Dale...Dale FINCH (female)!

[Stevetractor]

Oops. Sorry. Can’t read either Dale Finch

[Matt Kirsch]

Any luck with this? Just a bit of advice, whatever you do, do NOT try to force it together using bolts.

The splines in the input shaft have to line up with the splines in the clutch disk, and then the input shaft has to go into the pilot bearing in the flywheel. You have to wiggle jiggle and twist until it comes together smoothly on its own.

[Old Man]

No luck yet. I’ve worked on this for several days with no luck. I had blocked the front and rolled the back away so I attached a shop crane to the front to give me a little more wiggle jiggle room but to no avail. The pilot bushing is big enough and I used a spline tool to line up the disk. I removed the steering column so it’s not an issue. I decided against forcing it together using the bolts. I’ve had bad things happen when I did that in the past. This is very frustrating and not good for my blood pressure. Lol.
It’s kinda hard to tell for sure, but when I rotate the shaft by hand it seems like the end does a little waggle. Maybe the shaft is bent??? The old parts I removed were a mess. The front and back halves of the disk were loose. The tob was trashed on one side. The pressure plate had been rubbing the tob hanger so much that one of the spring adjusters was nearly worn off. What does that mean? Is the shaft bent??

[tst]

you can just spin the shaft by hand to see if its bent

[Glen]

The front and back halves of the disk were loose.

Hi,
I'm not sure what you mean, maybe the 2 linings had come off the metal part of the disc.
The rivets might have broken off.

The pressure plate had been rubbing the tob hanger so much that one of the spring adjusters was nearly worn off. What does that mean? Is the shaft bent??

It probably means that the pressure plate fingers were adjusted too low, and the throwout bearing had to go too far ahead, to make the clutch release.
Or someone might have adjusted the clutch pedal free play wrong, and the throwout bearing didn't need to push the fingers so far ahead.

The throwout bearing can only go so far ahead, until the metal part of it, or the holder hits the turning finger adjustments on the pressure plate.
The fingers have to be adjusted to the right height, so the clutch releases before the bearing or holder hits the turning pressure plate.

Turn the long clutch shaft while the Cub is split. Turn it slowly, and look closely, use a good light to see it. It should be straight.
They can get bent, one way is probably when someone splits a Cub, and something moves down before the shaft is out of the clutch disc, so the shaft is supporting weight, it can't support weight.