Check your splines!

[marrmanu]

Putting my B2620 back together and the mid front axel drive U joint line would not go onto its drive shaft. A closer look reveled this! Cost of a new U Joint $130 cost of further damage .

 

[Henro]

Can't see internally, but are you sure the shaft that is inserted is not machined the same way so it can only be assembled one way?

My monitor shows so little of what is inside that wide area, but what little I can almost see does look like a spine could have broken off...

 

[GeoHorn]

Looks like it is “keyed” to assemble only one way…..this would keep U-joints properly in-phase.

 

[BruceP]

I see nothing wrong with your photo. It is normal for shafts with Universal-Joints to be keyed. (especially within the slip-yoke). This prevents improper assembly.

U-joints MUST be properly phased so the matching joints at each end are bending at the same time.

Technically: The shaft itself is not spinning at a constant speed....but the phased Ujoints at the ends cancell each other out. This is why you NEVER see a shaft with just a single Ujoint on it.

This is one reason FWD cars use CONSTANT-VELOCITY (CV) joints. There is no need for phasing becasue the velocity (rotational speed) remains constant regardless of angle. CV joints are more expensive and cannot handle the torque when compared to Ujoint of the same size.

 

[dirtydeed]

I understand the Keyed reasoning. But, it looks like in the OP's photo that a spline actually broke. The machined edge doesn't look straight in the photo (looks like piece broke off instead).

 

[Tughill Tom]

I blew up the photo and its a broken spline.

 

[BruceP]

If it really is a broken spline... I would just run it the way it is. (and hope the broken peice did not get into a gearbox)

It is not the splines which hold the joint together so even if ALL the splines were to shear off, the worst it could do is spin on the shaft.

BTW: The splines on my G5200 driveshaft are nearly non-exantant. All of them come to a sharp point and there is a lot of slop. Been that way for many years and keeps on truckin. (it spins at ENGINE SPEED to drive the HST in the rear)

 

[imnukensc]

Nothing wrong with that u joint. The splines are keyed as previously discussed.

 

[BruceP]

I blew up the photo and its a broken spline.

I am not sure how you can tell.

Think about the machining process to make this component. It may be easier to make ALL the splines then machine one off later when the phasing is known. This could leave behind something which APPEARS to be the remnants of a spline.

 

[Tughill Tom]

I am not sure how you can tell.

Think about the machining process to make this component. It may be easier to make ALL the splines then machine one off later when the phasing is known. This could leave behind something which APPEARS to be the remnants of a spline.

Nothing I ever broached /keyed looked like that

 

[lynnmor]

Spline is broken off, not only that, but the tips of adjacent splines are knackered as well.

 

[lugbolt]

I wouldn't be afraid to throw it back together.

Have seen them MUCH worse

typically when splined shafts are worn, they are slick. No splines left. Or extremely narrow splines.

That one is a master splined shaft. They just broke the one spline off instead of machining it. Probably cheaper to manufacture that way.

 

[marrmanu]

Geohorn and BruceP you nailed it! Your post very much makes sense and after spending 3/4 of a day and driving over 100 miles, the second dealership I went to told me this spline is not broken, it is missing to act as a key. The drive shaft end to which it mates to has a bur on the end (I almost filed it off in preparation for the new U joint) to which the U joint would line up to.
Done lots of work on cars, trucks and motorcycles, but just starting my learning curve on this type of equipment.
Thanks all for throwing in to help.