U Joint Maintenance?

[xman]

This year I did tires, and did all the rear end and pinion shaft maintenance. I cleaned and greased the drive shaft spline before pushing it back into the rear side of the U joint. I assume the U joint has sealed bearings and no zert fitting, correct? I read how tough it is to get the U joint boot on, so before touching it to take a look in there, I ask? Do you need to grease the engine spline into the Ujoint? If so how do you do it?

Thanks Tom

[John Schmidt]

Getting the boot back on the engine is no problem. However getting it back on the swingarm presents problems for most due to lack of clearance. If you do pull the boot off the swingarm, before trying to reinstall it lift the rear of the swingarm(s/a) as high as possible. That creates the most clearance between the frame and the top of the front edge of the s/a. As for installing the driveshaft, you'll find it easier to mount the final drive if you install the driveshaft in it first, then insert the driveshaft into the u-joint. Pressing the final onto the d/s after it's already in place into the s/a can sometimes be a difficult proposition.

[xman]

Thanks John, but before I do anything.

What is there to do under the boot?

My guess, inspect the U joint and apply fresh grease to the engine side spline. Can you do this by taking off only the engine side of the boot?

Also, I don't have the drive shaft out so maybe this has to wait until I do rear end maintenance.

Tom

[Hoser]

Just goop up the end of the driveshaft splines and reinsert it, you can get enough grease into the ujoint splines that way.  Waterproof grease btw.  Hoser 

[John Schmidt]

You can pull the boot back from the engine and see part of the frontal area of the u-joint. Not sure how much though. If grease is visible when you pull the boot back, then I'd say you could wait until you pull the rear end off. Just be sure to do as suggested and use waterproof grease on that area.

[JaysGone]

Just a question?
Can you pull the boot back at the top and just fill the boot with a liberal amount of grease using a grease gun??
Cleaning up the mess later........

[GOOSE]

all you are going to do with that thought is to make one heck of a mess.

[JaysGone]

I know but if it coats the entire u-joint.
Then to me a little clean up is worth it.
If most think it would just shead it.
Then not owrth it.
Rather then taking the rear end off again.
I just did the splines and stuff recently.
It had seemed getting the boot off at the time was more trouble then it was worth.
So I didnt even try.
I dont know that its ever been touched in 13 years.
I dont mean fill it up.
Just a good blob injected in there.

[Bone]

You probably won't get many replies from people that have done what you suggest. Almost all of the area you will cover doesn't need lubrication. I just replaced a U-joint. I do a final drive maintenance every 10k this failure happened 5k after the last maintenance.


The cup the needles ride in wore away on one side. The joint needed lubricant pulling it completely the joint wouldn't have been lubricated without total disassembly. Greasing a Zerk would have injected grease where needed. I didn't notice any thing wrong 5k ago but honestly I just greased things.
95k on the joint that failed.

[Willow]

Just a question?
Can you pull the boot back at the top and just fill the boot with a liberal amount of grease using a grease gun??
Cleaning up the mess later........

Depending upon how much grease you put inside that boot, the slinging of that grease against the inside of the boot may dislodge or damage it resulting in a leak.

I can't see that it would do any good thing.

[Ricky-D]

Most damage to the bearing cups can be attributed to bad mechanical practice.

Namely allowing the swingarm to come to stop (bottom out) after removing the rear shock absorber bolts.

The edge of the cups are extremely fragile due to the machining for the seals.

Many threads have warnings about supporting the swingarm when disconnecting the shocks.

***

[Bone]

If I'm disconnecting shocks I do support the swing arm. I have a wooden support cut to correct length to level out the swing arm for drive-shaft reassembly. I could have damaged a cup and didn't know it I noticed the one cup with a very thin side from wear.

[xman]

Rick, you may have something. U joints can't be turned when they are past a specfic angle. I know it won't turn with the swing arm down. That said as long as you don't make it turn it should be ok. As Rick said droping the swing arm hard may bottom out the joint, pull it apart.  When I did the rear tire  and service, I used a overhead come along to raise and lower the swing arm.

So as I understand the U joints 4 bearing are maintenance free, no greasing. The drive shaft spline gets cleaned and good glob of Belray when you pull the pumpkin and drive shaft.

Greasing the other side of the joint spline, say a prayer it makes it  until you have to pull it apart to to replace the joint.

Tom