Found my noise!

[Josh D]

Gear lash noise under load + gear lever in 2nd moving backward under load pointed me to output shaft walking. Well, I was right......

Pulled motor/trans and first pulled side cover and diff. I caught it right in time as the R&P are still in perfect shape, but there was about 2 MM of for/aft axial play on output shaft. Further dissassembly showed why.

4 point bearing had axial play as well a trashed inner race (on the pinion side). The bearing retainer and pinion shims were beat to hell, and the roller bearing race was spun in the case.

The good news was that the rest of the trans was in great shape! All teeth present and accounted for! Plenty of friction material on synchro bands.

Out she comes! First time drop. Did it in just under 4 hrs by myself!


4 point bearing race


Shims beat to hell


Beat up retainier


This surface should be flat. Look at the trough that had been beat into the retainer by the bearing


Rest of the guts

[ChrisBennet]

A lot of times the bearing race is loose in the case. I *think* that bearing is supposed to be a slight press fit. They seem to pound out the case and get loose. Could you spin the bearing race easily in the case with your fingers?

[Josh D]

Originally Posted by ChrisBennet

A lot of times the bearing race is loose in the case. I *think* that bearing is supposed to be a slight press fit. They seem to pound out the case and get loose. Could you spin the bearing race easily in the case with your fingers?

Yes, I mentioned that in my original post. I dimpled the raceway and used Permatex bearing mount to hold the race in place. I know not everyone on Pelican recommends doing this, but this was suggested by a well respected Porsche independent shop owner in Tempe, AZ who has performed this fix many times with good results. There was no side to side play between the case and the race, it had just become a slip fit.

[Joe Bob]

Recommend the WEVO bearing retaining support. Welcome to Windrush Evolutions - WEVO - Porsche Products

[john walker's workshop]

a wevo tensioning plate is a wonderful thing.

[tctnd]

You don't have a jeep, do you?

regards,
Phil

[Charles Freeborn]

Originally Posted by Josh D

Yes, I mentioned that in my original post. I dimpled the raceway and used Permatex bearing mount to hold the race in place. I know not everyone on Pelican recommends doing this, but this was suggested by a well respected Porsche independent shop owner in Tempe, AZ who has performed this fix many times with good results. There was no side to side play between the case and the race, it had just become a slip fit.

Depends on your anticipated use and expectations. If a case is out of line or spec, well, then it's.....

-C

[Joe Bob]

When I did my repair, Aase Brothers cut the bad section out, pressed in another with a new bearing shell, added the WEVO retainer and it's been great for 5+ years.

[Jcslocum]

Originally Posted by Josh D

Gear lash noise under load + gear lever in 2nd moving backward under load pointed me to output shaft walking. Well, I was right......

Help out a noob here, I have a '66 - 912 with the 901 5 speed. I notice that the car will rock back and forth in gear a bit more than I have ever seen in another car. I also have a G50 Targa but that is another animal altogether.

Is some slack/rocking normal in the 901? There are no noises at all in any gear and she shifts OK (as good as this trans can) after I added the new shifter and coupling.

Right now I have RedLine NS gear oil in there but I'm thinking of making a change to Swepco or Kendall to see if the shifting can get even better.

[Josh D]

Originally Posted by tctnd

You don't have a jeep, do you?

regards,
Phil

Jeeps have been my passion/hobby for over 20 yrs. I've had up to 5 running and driving at one time. I'm down to two; a highly modified '95 YJ and a mildly modified '71 J2000 Gladiator pickup. If I run into too many more expenses with the 911, I might have to sell the '71 Jeep pickup to cover the costs!!

[Josh D]

Originally Posted by Joe Bob

Recommend the WEVO bearing retaining support. Welcome to Windrush Evolutions - WEVO - Porsche Products

I want to do the single piece retainer, as well as a machined case with steel sleeve, but it's just not in the budget right now. I broke my cardinal rule of function over form and spent a bunch of money on ducktail and paint work for ducktail, F/R bumpers, F/R valances, as well as Euro H4's a couple months back. I also had a bunch of while your in there expences with the engine and tranny out. The CFO is not happy with all the money I've spent on a car that I told her "needed nothing" when I bought it! Trans is getting a new 4 point bearing and good used retainer and shims I picked up for $60. I figure the trans will need a total rebuild in another 50K miles or so, and will do the upgrades then. In the mean time, I'll just have to take it easy on the launches!!

[Josh D]

Originally Posted by Jcslocum

Help out a noob here, I have a '66 - 912 with the 901 5 speed. I notice that the car will rock back and forth in gear a bit more than I have ever seen in another car. I also have a G50 Targa but that is another animal altogether.

Is some slack/rocking normal in the 901? There are no noises at all in any gear and she shifts OK (as good as this trans can) after I added the new shifter and coupling.

Right now I have RedLine NS gear oil in there but I'm thinking of making a change to Swepco or Kendall to see if the shifting can get even better.

I'm not a 901 expert (or a 915 for that matter). There is a lot of potential 'slack' points that could cause what you describe, such as mounts, CV joints, etc.

[Joe Bob]

Good luck....I just hope you don't have to pull it apart down the road...again.

[Josh D]

She made it almost 100k miles without the single bearing retainer, I think she'll go a little longer. Would be nice insurance though.

[Joe Bob]

Well, yes....but now it's a repair with a dimple to keep the bearing shell from coming loose again.

And to be fair, my failure was after a 3.6 install and hard launches in a couple of seasons of hard DE and AX use. The bearing got loose and took out second gear. It was a PITA and I sure don't want to consider doing it again.

I had an assist from a friend and even better sources for the machine and parts......

So....the plate install is pretty straight forward....bolt in w/o mods. The plate is stock in the 930 trans. I just think it's good insurance for a couple of hundred bucks.

[Josh D]

So once the new 4 point bearing arrived I did a test fit into the used replacement bearing retainerr and the fit was recessed rather than flush or proud of the retainer. I went ahead and did a test mount of the bearing with the retainer and shims on the cases without the shaft in place and it was not good. Way too much slop in both radial and axial planes. Not going to work!

So I took the advice of JW and Joe Bob and went with the single bearing retainer from CMS. It's a very nice piece of hardware!



So now that the mainshaft has to come apart, some tool fabrication was in order. I took a page from Jim Sims book and welded the smallest 1/2" drive socket I had as a spare and welded it onto a 1 5/8" socket. I had to cut down the 1" drive 1 /5/8" and bored out the center with a torch to slip over the shaft. Gutted the old clutch disc to hold the the mainshaft at the splines which fits perfectly in the jaws of the vice. Supported everything with a pipe fitters tripod. It all worked great!





I got the gear stacks reassembled with the one piece retainer in place. I found it easier to do the pinion shaft first, then ziptie the two gear cluster togeher in two places (didn't take a picture), then press on the mainshaft 4 point and roller bearing. I couldn't find any threads on how others had done this with the single piece retainer, but this method worked for me. I then mounted the shafts and gear clusters into the case with the replacement shims.



This is as far as I've gotten with the tranny while awaiting the shift fork jig, which is taking painfully long to get shipped.

In the meantime, I've spent a majority of the time cleaning the engine and all the other parts. Sodium hydroxide works great for this!



After some spit and polish, paint, and a bunch of new seals and gaskets for the engine and CIS, the engine is anxious to return to duty! Still awaiting the new plug wires and clutch alignment tool to finish.



With tins


I've been agonizing not being able to drive my car. It's only been about 6 weeks since I stopped driving it due to the tranny issue, but it's downright painfull. I don't see how some of you can put these cars away for the winter or only bring them out on nice sunny days!

Thanks again to all the Pelicans that have travelled into this territory before and left many great threads to learn from and those that are always there to help steer in the right direction.