With the Fun Projects pinion I don't need to face the drive shaft bushing for a thrust surface, but I do need to shave it back a bit for the U-joint and drive shaft holes to line up. Before I whoop off sixty bucks for the facing reamer, I'll ask if there's a cheap and easy way.
From an earlier thread:
Did the bushing fit the drive shaft before you pressed it in?
If so you don't have to buy an expensive reamer for a one off job - you can just drive the bushing out again and make some holder out of screws and washers so you can mount the bushing in a drill press and take down the outer diameter some with a file or / and sand paper - that's if you don't have any lathe.
Then when the bushing is a slip fit in the driveshaft housing, you can glue it in place with your favorite epoxi with the drive shaft as a guide
(Just be sure to drill the grease hole in the bushing too)
There is another reason to give the bushing a slip fit, that's so you can test fit the axial play in the drive shaft with the u-joint in place, if there isn't any play or if it's too small, the bushing can be removed for easier adjustment of the thrust lip end. Another expensive reamer you don't have to buy
Steve, just knock it back out and use your belt sander. The 'hand' reamers they sell are junk in my opinion. I found a vintage one that I use and it is ten times the tool they sell.
I have both original and the new facing reamers - neither work efficiently on brass/bronze or whatever the reproductions d.s. bushings are made from BUT they "cut like butter" on N.O.S. Babbitt ones !
Why bother facing it all? I never put the ujoint pin in when I use a modern pinion cartridge, have yet to have a problem with this method after thousands of miles. It also makes changing the ujoint later on tour in the parking lot one step easier.
What jeff says is true, only way I do over 50 k on the last one and still going. KGB
Its been a long time ago since I did my tail shaft, but from memory I cut a piece of ply into a round disc glued some wet and Dry paper to it drilled a hole and placed a bolt through the centre tightened a nut to clamp the disc and placed it in a drill and sanded it down until the pin would fit through the uni joint and shaft.
My driveshaft was worn enough I did not need a reamer. I faced off the flange to the same thickness as the one I took out and the u joint and pin lined up with almost no play. The thrust is always going to push the pinion outward so there should be minimal wear on the face of the bushing. On both rear ends I have taken apart the u joint pin was sheared . Jeff is correct, things should be fine without it . With no pin the u joint will find the place it wants to be and be happy.
I just installed a NOS babbit front bushing in my '13 last week. It didn't need reaming, but I did have to face it to be able to get the pin through. The driveshaft had .001 wear.
I don't have the time right now to explain the "rest of the story" but, I'll suggest that you don't just lop off a chunk of the flange, but instead, trim it back to give maybe .005/.010 clearance from the back of the u-joint. That way, it's not in contact but, should the F.P. locking collar slip on the driveshaft, the bushing flange should take over.
This is NOT a criticism of the F.P. set-up but I did a rear end rebuild where the collar did slip and caused the driveshaft to slide down way too far into the rear axle housing. I have since added a spacer behind the u-joint as insurance against a future occurance.
"With no pin the u joint will find the place it wants to be and be happy."
No, it won't. It will slide fore or aft until it begins to cause the joint to bind, at which point it will scoot in the other direction to the point of binding, and so on, and so on, until the u-joint is worn out. Read the F.P. instructions, I believe it suggests you use the pin. The u-joint only operates efficiently and correctly when its hinge point coincides with the center of the torque tube ball & socket assembly. Any other location will cause wear. I'm not saying it will be gone in 100 miles, but it WILL wear faster.
Steve, you could always face off the rear of the u-joint, rather than the bushing.
Jerry is correct that leaving out the pin is not a good idea. Also there is no reason that the collar should ever slip unless something is wrong. That collar can handle more than 10 times the side force it "should" be dealing with. The collar only carries the proportional weight of the upper ujoint and all of the drive shaft parts. If the drive shaft were vertical then the collar would carry all of the weight of the items fastened to the drive shaft and all of that weight would still be well within the side force that the collar could deal with. If installed loose or if the ujoint is not pinned then the various parts can "hammer" against each other and that presents a larger side thrust load. The new ujoints being oversized and not fitting smoothly into the back end of the drive plate on the transmission could then ram the shaft down but the collar if installed on the smooth 1.000 diameter portion of the drive shaft is not going to move without something wrong somewhere big time like the over sized new ujoint issue recently uncovered. I just opened a rear end (my own) with over 50K miles on it and there was no wear on the collar nor any endplay in the drive shaft assembly. Always check the ujoint for a nice smooth slide into and out of the back of the motor before you install it to the driveshaft if you are going to use one of the new ujoints.
I have some n.o.s. babbit ones if anyone needs them, Bob
Steve, you don't say how much needs to be removed but you can always remove some from the U joint itself on a belt sander just food for thought
You state, "...there is no reason that the collar should ever slip unless something is wrong"
I agree. The situation that caused the collar to move on the car in question was as follows. First, the u-joint did slide freely in the output shaft. The main problem was that the owner of the car put a gasket on both sides of the fourth main flange. The gasket between the ball retaining ring and the 4th main flange caused excessive fore-and-aft play in the ball joint. Even though the u-joint slid freely in the output shaft under no load, it would not slide freely when loaded with braking or driving torque. So, while braking, torque tube ball was pulled back against the retaining ring. When starting out in low, the ball was thrust forward into the excessive clearance created by the gasket, (which was a really thick one to boot). At the same time, the u-joint, while loaded with torque, could not slide freely in the output shaft so it put a rearward thrust on the driveshaft and ultimately, against the F.P. locking collar. After repeated stop-start cycles, the driveshaft was driven back until it hit the differential carrier and wore a big groove in it.
So, the moral of the story is DON'T use a gasket between the ball joint retaining ring and the 4th main bearing. And, be sure that the ball socket is not otherwise worn such that it allows excessive fore-and-aft play. (There is a shim available to take up this wear.) I also feel that removing only what is necessary from the bushing flange to create a minimal clearance is also good insurance.
Again, I don't blame John's design for this issue but it's a possible situation to be aware of.