check out the diff housing, in a drilling right between the holes where the shift rods were, and see if the detent is still sitting there. if the housing was jostled or plunked on the bench after the gears were removed, the detent may have relocated itself. this is a very important detent and has to be in the right place when you reinstall the shift shafts. it often slides up into the top of the bore and is forgotten until the trans goes into two gears at once farther on down the road. there is another one in the end of the intermediate housing.

I'll take a look.

I had it standing on the bell housing when I removed the shift rods. It was sitting on the floor with my feet holding it in place while I pulled the rods. I don't think I jostled it around, but I'll definitely take a look.

Getting anxious to get this thing apart so I can get the parts on order. I'll probably need some help identifying all the parts. I'll post pics of the pieces and will leave it up to you experts.

Randy

John, here's a pic of the diff and the holes where the shift rods were. There is a bored hole that goes somewhat at an angle between the two shift rod holes. My guess is this is what you'rre talking about.

I can see the detent. Looking at this pic, the detent is in a recessed area that runs to the left of the hole on the left, if that makes sense...
http://forums.pelicanparts.com/uploa...1083362736.jpg

If I'm correct, the shift rod on the left is for 1-2, and the one on the right is 3-4. There is another drilling in 1-2 that runs away from 3-4. That is where the detent is.

Anyway, thanks for this piece of knowledge. I wouldn't have noticed that on my own.

Randy

Here's a better shot of the detent.
http://forums.pelicanparts.com/uploa...1083363038.jpg

Randy

edit: John were you saying that this detent should be in the drilled hole BETWEEN the two shift rod holes?

the detent lives in between the two shift rod holes, cross-ways. it is loaded into the bore originally by removing that steel cap on the outside of the case. there's a like steel cap in the intermediate cover for another detent.
how is the condition of the big flat shims that were under the retainer plates? they often get killed by the bearing lip. measure with a micrometer and replace any that are chewed.
how are the cast iron retainer plates? the lip of each bearing should stand just a tad proud of the face of the retainer when you pull them snug with your fingers. the lip should not be below the surface of the retainer, or the shaft(s) will have end play, which makes for a noisy trans.
remove the side cover and remove the ring gear assembly, and get all the metal bits out of there.

this is a pic from the 3-4 setup. The dog teeth seem to be in decent shape (IMHO). You can also see the hub and the thruster block. (Look at me, sounding off like I know what I'm talking about...:rolleyes: )
http://forums.pelicanparts.com/uploa...1083368069.jpg

Here is a pic of 1st gear (I believe). You can see the broken parts of the hub and the missing dog teeth which allowed the ring (Not sure the correct nomenclature) to release and drop the thruster block, allowing it to roam free around the transmission.
The reason I could not shift into first!!!
http://forums.pelicanparts.com/uploa...1083368493.jpg

Another pic of first gear, showing the broken hub, the ring which was released by the failed hub and dog teeth and the thruster block which was floaring around the case.
http://forums.pelicanparts.com/uploa...1083368765.jpg

A closer shot of the above pic showing the broken ub and the ring.
http://forums.pelicanparts.com/uploa...1083369440.jpg

Fixing to tear into dis assembly of this thing in just a bit.

Randy

Go Randy go!!:)
Ryan

Randy,

The "ring" is a syncho band or synchro mesh. It is the part that provides the friction surface to match the RPMs of the operating sleeve and the gear with its dog teeth before they mate and lock. It rubs against the inside of the operating sleeve. The whole setup acts very much like a drum brake: Once the operating sleeve (drum) gets pushed towards the synchro bands (brake pads) by the shift fork the anchor block and the thrust block push the synchro bands apart and eliminate the RPM difference between the two before they mate.

If you shift too hard the synchro's don't have time to complete their work and the dog teeth on the gear grind against the teeth of the operating sleeve. If the synchro band's friction surface is worn out the breaking effect lessens and the tranny grinds more.

Trust me, after you have put everything back together you will take each shift with a deep appreciation knowing exactly what's going on in the tranny. Ask me how I know.

Go Randy go, this one cool thread,
Ingo

915 brake bands and synchronizer (synchro) rings are distinct and separate parts. The brake bands are inside the synchro rings and do not contact the operating or sliding sleeve. They instead, bear against the inside of the synchro ring.

See:

http://forums.pelicanparts.com/showthread.php?s=&threadid=156043&highlight=synchr o

Ooops Jim,

you are right, it's been some time since my 915 was apart and I just looked at PET this time to get the names right. Totally forgot about the brake bands. PET diagrams are borderline. I should have taken the time to look at the factory WSM.

Ingo

Just a reference shot before I beat up my garage floor...
http://forums.pelicanparts.com/uploa...1083424235.jpg

Randy

And another...
http://forums.pelicanparts.com/uploa...1083424728.jpg

Randy

"The Usual Suspects"

First Gear...You can see the missing dog teeth.
http://forums.pelicanparts.com/uploa...1083426305.jpg

First Gear and the Synchro Band. My guees is that the Band should NOT be out-of-round like this one is.
http://forums.pelicanparts.com/uploa...1083426368.jpg

The Toothless Hub :D
http://forums.pelicanparts.com/uploa...1083426422.jpg

I'll continue dissassembly of the shaft and see if anything else looks damaged. I'm sure there will be more pics to come.

Randy

edit: By the way, is there a technique or a special tool I should use to get that C-Clip off of First Gear?

This bearing came from Second Gear.
http://forums.pelicanparts.com/uploa...1083428203.jpg

Everything else seemed to look okay. How far should I tear Second Gear down to inspect it. Here are a few shots of Second.
http://forums.pelicanparts.com/uploa...1083428558.jpg
http://forums.pelicanparts.com/uploa...1083428574.jpg

As far as I could tell, I wasn't having any problems with Third or Fourth, so I think I'm going to leave them alone for now.

Randy

Randy,

I would replace the synchro's on 1 to 4 while you have the tranny appart. If you are really cheap you can at least flip them over. They mostly wear on the side facing the operating sleeve. Take a look at the synchro rings, if you see dark spots on their outer surface near the gap the friction material is about to go. From what I understand new synchro rings have better material and wear less. But that could also be a rumor. The last photo shows the circlip in all its beauty and the dog teeth. But again, take a look at the outside of the synchro rings.

I don't know for sure but I think you can reuse the needle bearing. If I remember I had one cage cracked like that and reused it. No biggy.

Ingo

Randy,

There is a major disparity between the 1st gear dogs (worn and broken) and the 1st gear side of the sliding sleeve (not terrible). Had the sliding sleeve been replaced recently and not the 1st gear dogs? Is there something else going on here?

It seems to me that when things started to fail, attempting to force it into first may have caused this extensive damage. The important diagnostic is what precipitated the first problem.

Best wishes,
Grady

Ingo!

Are you back from Taiwan?

Yeah, I am trying to fix this as cheaply as possible. From what I can see so far, and following your recommendation on the Synchro Bands, this is what I'm looking at:

Synchro Bands: 1st through 5th
Synchro Hub: 1st
Synchro Hub Tool: 1st Gear
Tranny Gasket Kit
Shift Shaft Seal
Needle Bearing: 2nd Gear

From what my inexperienced eye can see, the rest looks okay.


Grady,

I'll get a pic of the sliding sleeve so you can compare. Took me a bit of playing with the parts to figure out what you meant, but I've got it now. Anyway, there has been no work done in this area for at least 5 years....let's say, maybe 5,000 to 10,000 miles.

As far as symptoms preceding this, there were a few. First, there was the other thread I linked to at the beginning of this thread. I was stuck out of First AND Second gears, but jostling the shifter "freed" it up.

Prior to that, I had occasionally experienced a symptom I've seen recently posted here. Basically, it was an extreme difficulty in shifting to Second. It was extremely intermittent and was difficult to duplicate. It happened whenever it wanted to, no matter how it was being driven. Double-clutching seemed to "free" up second.

When I had her in the shop for her 90K service, I mentioned this to my mech. He said he would check it out but was unable to duplicate it. I suppose I should have torn into this at that time, but.....here I am :)

Randy

Here's a pic of the Synchro Band showing just how much it was torn up.
http://forums.pelicanparts.com/uploa...1083441109.jpg

Here's the sliding sleeve.
http://forums.pelicanparts.com/uploa...1083441894.jpg

One thing I noticed was that the points on these gear teeth are offset on one side and centered on the other.

And here is Second Gear with the Dog Gear. The Dog Gear actually has a little play, in that it can actually come 'out" almost 1/16th of an inch. I can pull it out this far and then press it all the way flush as well You can see that in this image.
http://forums.pelicanparts.com/uploa...1083442068.jpg

Randy

Randy,
I don't know how you do it, but everyone of your photos is beautiful, almost lyrical. Great lighting and composition, lovely colors. Someone who can't read might well think this is a thread about the beauty of engineering.
Keep 'em coming!

Let us have a poll... How many pieces do you think Randy will have left over when he is done putting it back together? Seriously, You got balls Randy, boy!

Beethoven,

That's quite a compliment, coming from someone with YOUR musical background! THANKS!!!! :D

Seriously, though, I'm trying to do as accurate a job as I can, with clear pics because this is my instructions for getting this thing back together! Well, this along with the help of John Walker, Ingo, Matt, etc...:)

And Doug, hopefully, the only parts I end up with when all is said and done are the ones that are already trashed! They say that ignorance is bliss, but this honestly doesn't seem that difficult...yet! :) Although I do still have quite a bit to go before it's finished.

Randy

you should replace both 1st and 2nd press on teeth, all syncros, all brake bands, 1+2 shift sleeve, 3+4 shift sleeve. just because 2nd teeth haven't broken yet is no guarantee that they won't in the future. look at all the other teeth. hold them up to the light and look at them cross-ways and see if any are worn into a hook shape, or are getting flattened on their otherwise pionted tips. the 1+2 shift sleeve is going to be worn where the syncro rubs on the inside of it. 3+4 shift sleeve will be worn as well. when you get it off, you generally see that the inside area on each side, that first contacts the syncro ring, is worn a lot wider than when new. might as well do it right, so all your efforts produce a nice shifting trans, instead of one that's still not quite right.

John,

I took a look at the shims (there were 2) under the cast iron retainer plates. The looked fine...they were flat, with no mashed edges or creases.
http://forums.pelicanparts.com/uploa...1083448321.jpg

You also mentioned the cap that allows access to the detent between the two shift rods. How do I remove that? Do I just grip it with a pair of pliers and twist? Pry with a screwdriver?

Gonna have to re-visit my parts list and see how much more it will be to add the extra items you mentioned.

Randy

the caps just pry or tap off, but there's no reason to do it unless the detent gets stuck up under it and won't come down.

I bow my head in awe for Randy. For someone who couldn't tell a rear sway bar from a tranmission crossmember a couple of weeks ago Randy has done one hell of a job. I was frankly scared he would crush himself with the engine landing on top of him. Instead is he is well on his way to fix a serious problem with his tranny. That's what this board is all about. Every time I open this thread it reminds me a little of the Trueman show. :)

And Randy, nope, still in Taiwan. I won't be back until Friday. One more week of mayhem. Think one million scooters trying to get from point A to point B at the same time. No rules, just like Cannonball racing. Traffic is like the lottery here. If you get lucky you make it in one piece.....

Go Randy Go

Ingo, I lived in Taiwan for over 2 yrs and drove there. Like the start of Le Mans every day.

Where did you live? I spent the better part of a year in Hsinchu in 2000 and always drive myself. Driving is more fun here. Still no rules, drunk, speeding, against one-ways, red lights are all no issues when you are foreign. Police sees your foreign face and looks the other way. In Taipei things have changed. Policemen do speak english there. I am lucky since I can pretend to not speak english when getting pulled over. I just show my German passport and usually get away with it :)

Ingo

Ingo, if it wasn't for the guidance I received from everyone on this board, I probably WOULD hav crushed myself! I have to really give special credit for preventing that to Jay and Josh, my local Pelicans. http://www.pelicanparts.com/support/smileys/wat6.gif

And yes, I have to agree with you. I have learned so much about my car by doing this. As fas your "crossmember/sway bar" comment, I have to correct you on one thing. It wasn't "a couple of weeks ago" it was just LAST WEEK! :eek: But I've got it now...thanks a lot!

I've never been to Taiwan, but I have spent time in Thailand, racing through the streets in Tuk-Tuks. You really develop a sense of fearlessness when you ride those things and play chicken with buses and other big rigs.

Randy

Randy!!
Enough with the chatter already! We're all sitting here waiting for your next moves.
Back to work!

Randy,

I can send you the PET6 info by fax or by e-mail as .dat files. E-mail me and let me know; gradyclay@hotmail.com.

In the interim, I’ll compile a part number list to post.

Best,
Grady

I've been doing some searching for parts and ran across the following Synchro Band. What's the deal with the notches cut out of it?
http://forums.pelicanparts.com/uploa...1083519385.jpg

Randy

Lets see if this works.

http://forums.pelicanparts.com/uploa...1083523189.jpg

Best,
Grady

that's the 2nd gear brake band. the 1st band has an offset notch, the longer side of which goes to the left if you look at it with the gap at the top. the notch holds a stop dog, different for 1st and 2nd.

grady, that pet stuff is copyrighted. don't want to get wayne in trouble.

John,

Yes, and there is something called "Fair Use" and this fits within that definition.

Best,
Grady

Randy,

The first number is reference to the diagram. The next number is the part number. It may have been superceded but any Porsche dealer can get you the current number. In “quotes” is Porsche’s description of the part. Next is my US description because occasionally something is lost in the translation.
“This is for the 1-2 gears;
- no 1st gear dogs, available from out host
44 915.302.315.01 “energizer 1st gear”
45 928.302.321.00 “stop”
37 928.302.319.08 “double brake band 1st gear” 1st gear syncro
40 915.302.311.01 “locking ring” circlip
5 999.201.138.00 ”needle cage” 1st gear needle bearing
41 930.302.401.01 “guide sleeve” 1-2 hub
42 930.302.411.02 “shifting sleeve” 1-2 sliding sleeve
- no 2nd gear dogs, available from out host
39 915.302.301.06 “synchronizer ring 1st speed” Actually 2nd gear syncro.
5 999.201.138.00 “needle cage” 2nd gear needle bearing

Now for the rest of the gears;
Some may only benefit from replacement, others may absolutely be necessary. Only careful inspection will tell.

13 911.302.411.20 “shifting sleeve” 3-4 sliding sleeve
10 911.302.301.06 “synchronizer ring” 3-5th gear syncro
plus other parts?

While some reuse these parts if they “look good”, I prefer to rebuild with these new parts every time.
51 915.302.282.00 “shoulder nut” pinion loc-nut
20 915.302.281.00 “shoulder nut” input shaft loc-nut
25 900.309.005.00 “pin 4x26” input shaft castle nut lock pin
47 915.302.268.xx “Pinion shim” adjustment shims for the pinion”
and of course the complete gasket-seal kit.

I think there is an important issue of finding any other parts that were damaged by the errant 1st gear syncro parts. These are subjective and difficult decisions where there is no “right” answer other than “replace everything.”
First, I would inspect all the gear teeth for damage. Next, I would inspect all the bearing surfaces, particularly those under 1st and 2nd free gears. Disassemble everything for inspection and cleaning – these were hardened steel parts that went through the machinery.

When cleaning, use Stoddard solvent or WD-40 at this stage. You don’t want to have any hardened and ground parts “lacquer thinner clean” and dry because they will rust.

Keep us up to date.

Best,
Grady

Randy, your operating sleeve hub looks as though it's been damaged -
JW, can you comment on this?

As far as the 3rd and 4th are concerned, if you choose to replace the syncros and operating sleeves, then you'll need to take that shaft to a machine shop (or porsche shop) to have them press out the bearing, then you'll need my tool for tightning the 41mm collar nut.

If you're trying to save money, the first thing to drop is the syncro for 5th. You can just flip that guy and it's probably not warn anyways (mine wasnt). Then I would say to drop the 3-4 operating sleeve, that will save you another $100. Then, I dont recommend this, you could drop the 3rd and 4th syncros.

If you're really on a budget, then I would do what I recommended to the degree you can afford. I understand what it's like to be on a budget. Good work thus far brother.

Hey, Matt!

I've decided (actually, my wallet decided) to just stick with 1st and 2nd gear. 3 and 4 have behaved themselves so far, so I'm gonna chance it.

I'm going to change out the teeth, the bands, the sleeve, the hub and the brake bands. Hopefully that will get me where I need to be with 1st and 2nd.

This thread will probably slip way back from Page 1 for a while, but when my parts get here, I'll be bumping it right back to Page 1 all over again. I'm trying to document as much as I can so others can benefit from all the wisdom and experience on this board like I have. I'm still in awe at how easy you all have made this so far.

Looking back so far, I think it's kinda cool that I've come this far without once sticking my nose into a Tech Manual. I mean, technically, I've looked through Wayne's book and have read some tech articles from Pelican, but other than the exploded diagrams that have been posted, I have yet to read the manuals. All you guys are fantastic!

Randy

Any confirmation on the operating sleeve hub damage from JW? It sure looks to me like it's damaged pretty good and you'd hate to have it ruin your new operating sleeve at over $100.

We have not yet mentioned this, but your tranny gasket kit will come with new seals for your differencial and other parts. I used the ones which applied to my tranny and she's not leaking one drop. This is a concern when rebuilding a 915 is that it can leak. There's some things to be careful of when replacing some of those and there's a right and wrong way. When you get there, ask questions :) (Like I have to remind YOU of that)