Timing drive shaft damage

You are spot on about the fatigue bit

 

Mike, on second thoughts, I think I was actually wrong in this case-- getting old :-( As with conrod bolts, the huge 3824kg clamping force is well beyond the cyclic bending moment on the shaft so the fatigue is not such a big issue.

 

Has anyone replaced the small inner bearing on the timing cover? If so how did you pull them out? Many people made tools for the outer but nothing is written on inner.

 

Absolutely. It would be most interesting to learn, how this exotic damage could happen and not only how to fix it.
The damage looks as if it developed over a prolonged period and not suddenly. Failed/seized bearings are causing different damages like badly worn bearing seats on the shaft where the inner race is located.
I fear, that the steel suffered structural damage and fatigue and the part is far beyond its original strength specs. Restoring such a damaged part to its original specs would be more expensive than a new part. Welding material onto it and cutting without further structural tests is a hack job IMHO.

Best from Germany
Martin

 

Martin I wish I had a good explanation on how it happened. I always try to find the cause of the failure to avoid it from happening again but in this case I really have no idea. (it was there before me ) I still have the shaft at the machine shop and I'll wait until they get back to me with the results before going any further. It is concerning me and I will not put any part on the vehicle not feeling 100% secure about it.

 

This is the damage that was caused to the gear. It's not as bad as the shaft.


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Derek I have just received new bearings and it appears that some of our vendors are switching the bearing. Without requesting it they send me the 2RSH/C4.

 

The nut was loose so the cyclic force was on the key/slot which wore over time. As I mentioned before, the nut should clamp the pulley to the gear via the bearing’s inner race.

 

Agree the woodruff key walked out to the point of near failure....which could not occur without jam nut backing out.
Machining it new is certainly within reason, or agree with everyone this is a very important component...

We would joke, "find a low mileage GTS driven by a hair dresser" and salvage that....but that's no longer PC.
Ordering a new one I suppose is!!

 

I have started assembly of the lower cam gears and noticed that on one of the (outer) bearings I have a wobble . I have ordered a new bearing and I'm experiencing the same issue. Is this normal or I ran in to 2 bad bearings? The vendor supplied me with the 6203-2RSH/C4.

 

No mystery. Someone left the pulley nut loose at some point. They dont come loose, they are left loose. Not worth fixing. There are a huge number of junk, blown up and parts core engines out there. Get a used one.

 

Well the problem with the bad shaft has been taken care of. Is it acceptable to have some play on the outer bearing after the shaft has been installed?

 

No. You still have a bad shaft from the sounds of it. It should be a tight press fit

Can't imagine why you repaired it. I was just offered all the used ones I wanted for under $100 each. Guy told me he had a box full of them.

Do you know how many 308 engines have been parted out?

 

Is it the repaired shaft that is wobbling? That’s a clue. If the wobble goes away when you tighten the pulley nut then your shaft is not tight in the bearing. I’m assuming the timing cover is on with new inner bearings? Don’t forget the thin conical washers facing the right way against the inside clips.

 

The shaft went on the bearing nice and tight. Before I installed the cover I moved the shaft back and forth and saw some play on the bearing NOT the shaft.