Whats up ? New to the site and have a question about U-Joints. Im building a 50 merc that has a nova sub, 400/th350, 411 rear. I dont know what the driveshaft came out of, possibly a 78 lincoln or something. Anyway I took the old U-jonts out and matched them up with some new ones at the parts store. The front one by the yoke is smooth and easy to move up and down. The rear on the other hand is hard as a Mother to turn by hand. I havent greased them yet, so maybe that will help loosen it up, but I always thought it was suppose to be fairly easy to move back and forth after installing new ones. Could they be the wrong size ? They sure did look the same from the old one. If anyone knows if this is normal or something is wrong let me know. Im fixing to put the body back on and want everything under the car to be good to go before I do. Thanks for the help fellas
You may have a needle down in the u-joint cap or a pinched yoke. Looks at the seals on the caps, do you see a gap between the seal and the cross on one cap? If so, needle down. No unusual gap, you might be able to loosed up the u-joint by hitting the weld yoke ear behind the cap, hit both sides. If you have a needle down, you will shatter the needle. If this doesn't work, take it to Truck Parts Specialists in Houston to get it repaired. Good luck!
Man, I dont think I dropped a needle. The front u-joints by the yoke are good and smooth, the backs on the rearend just seem way to tight. I was careful when I put them in, but did have to beat the hell out of them to get them in. The clips went on fine, so I dont know, maybe its the wrong U-joint for that shaft ? There are no gaps anywhere on the caps, everything looks like it seated perfectly.
Sometimes we have to thin down the snap ring on a bench grinder, sometimes for both sides. I've also seen trash/shrapnel inside new u-joint caps. On that size of u-joint, there's not another series that has the same cap diameter with a minor cross length change. No such animal. You have one of the following---needle down, trash, or a pinched yoke. You shouldn't have to beat the hell out of one of those shafts to install a u-joint unless you have a rust problem in the cap holes.
Pinched yoke is an easy fix, support the drivesaft "tab" on a soft block at an angle, tap the other ear "the one that is now facing up" with a rubber mallet. The bind on the Ujoint will disappear as the Ujoint is seated evenly.
Where the joint is tight smack the driveline next to the clip area a couple times while trying to move it by hand if it doesn't loosen up hit it again then do the same on the other side,be careful not to screw up the groove for the clip.Hit it again it'll loosen up
There are slightly different thicknesses of the internal "C" type snap rings. Instead of banging on it with a soft hammer - which is ok - use a bench vise to press it apart and together. Sockets make good press tools here.
Snap rings in grooves on the u-joint caps don't apply to his problem. If the right person with the wrong vise and socket routine are used, the driveshaft yoke receiving the intended u-joint parts will get damaged. "Crank on it harder, it'll fit!" They didn't hear the crunch of a broken u-joint needle that had layed down. Snap rings fit just fine, but it feels crunchy, fff it. The next guy grabs a ball peen hammer, dents the end of a precision machined u-joint cap and collapses the outside ring land of the snapring that holds the cap in place. The snap rings won't fit, and the cross is now confined to a smaller dimesion than what it was made to fit within, it was machined the specified dimension. Fools with sockets, vises, grinders, welders, and hammers have helped me make a living since 1989. Vehicle dealerships, big truck builders, big truck dealership service depts, parts stores, dirt and drag car bulders ask for guidance and send "my shop" new, repair, and modification work. I have scars with part numbers associated to them. My right shoulder doesn't like cold weather, and the 3 lb. hammer in my toolbox shows some reason why. WTF do I know? C9, you're cool in my book, I'm just venting.
Having guys like you around is why I don't do my own u-joints. When my dad was building cars he taught me that there are some things that we are better off taking to the "pros". It usually costs less in the long run. Thanks, Mike
When the cap is pressed into the yoke it will actually distort/bend the yoke slightly. Hitting the yokes on all 4 sides will releive the pressure/stress and allow a properly installed joint move freely. Just a quick whap. Not a gorilla swing.
That is fine but Ujoints are really easy! I prefer having the help of a network of pros as well. My local connections also know when I walk in it WILL be a sale and I have a REAL question on fitment that breaks up their boring day! Doesnt hurt to send business with your name attatched on a regular basis! But knowing some of the "black magic" may save a guy struggling with a Ujoint replacement on the way to teh HAMBdrags or another event...... I typed my reply at work, same as the one below mine. No pics then and Photobucket isnt liking my Mac now. If you could see the SIMPLE way of freeing up a STICKY Ujoint you would go DOH!? just like I did a few years back when it was shown to me. Mr. Briitton, I know you know some of this already since you have been around, it was not meant as a diatribe against you but FOR others.
I've done lots of U-joints and sometimes when the new parts are put in, the pressing and/ or pressure you have put on it will make it tight. I simply tap the yokes with a ball peen hammer not too hard. This " relaxes " the metal on the yoke and you'll find it is nice and loose.
Several of us have said the same thing, we all suck since we dont have pics to show it! If a few taps dont do it, a guy needs to take it apart and start over.
And sometimes it's a simple as you went a little too far in with the caps, putting the cross in a bind. The snap rings fell right in, Now ya got to tap the joint apart a little to get the cap back to the snap ring.
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