1st Engine Drop and Tranny Rebuild

[infraredcalvin]

Gents, I just completed my first engine drop and I admit it was much less painful than I thought, it was actually quite simple. Man there's a lot of oil in these things, sad to say I've never done an oil change on this car myself. The need always seemed to coincide with other items being done at the shop (smog, alignment...). The reason I dropped the engine is because I started to get the dreaded 3 gear grind. I checked the bushings/ball cup, aligned the linkage, checked and topped tranny fluid to no avail. I also read this thread:
930 transmission overhaul
It scared the crap out of me until I sat down with the workshop manual and started reading up. I've decided I'm going to try and tackle myself... Famous last words...

Proof:

(ugh, I just looked at this on my computer, sorry for the sideways pic, it's rightside up on my ipad...)

[infraredcalvin]

Ok, so I've started a parts list and I'm stuck on a few items. I really need help from the brain trust.

Remember, I have a 76 930, it has the 930/30 transmission according to workshop manual. The 77 is a 930/33 and the 78 is a 930/34 - this becomes important in a minute...

1) The shift sleeve(1st/2nd) P/N 930-302-411-00 for the 76 is NLA, pelican and the PET reference P/N 930-302-411-011 M100 as the superseded part for the 77 930, but does not mention the 76. Can this be used in the 76? Any other items need to be replaced as a result of using this part, like the gear itself?

2) the Synchro hub (dog teeth for 3rd & 4th) is only listed in PP by P/N 101550 319 M157, for 77&78 MY, again no mention of the 76. Can this be used in the 76? Any other items need to be replaced as a result of using this part???

Finally in the workshop manual in the disassembly portion it states: "Place reverse gear shaft in bore of gear housing. Slide on reverse gear II as illustrated and place in 4th." Anyone have a dummies step by step pic of what they're talking about, the illustration doesn't look like it's showing anything different, maybe it'll make more sense when I open it up. But if this locks the shaft in place so I don't have to use an impact wrench I'd rather do this. I'm afraid the jarring of the impact wrench may be helping the needle bearings come apart which might have been what Aseem had experienced, leading to a seized tranny.

Any help would be greatly appreciated...

[Oheggem]

No help from me but please post progress pics Subscribed!

[krasuskyp]

I always feel like less of a man reading these posts! Never dropped yer own fekkin oil yet there's yer motor on the floor.

AND

yer DIY'in the trans to boot

I've changed plenty of oil on mine, still trying to muster the stones to do the drop. Prob will await 'need' lol.

No insight for you beyond confidence building reverse assimilation. Git'rdun / youcandooooit!

[infraredcalvin]

Thanks for the encouragement so far, I need it!

I did some searching around, and stumbled on the correct parts (I think), here is my parts list. I belive these are the main wear items, if I pull apart and see something else I'll order at that time. If anyone sees something out of line (unnecessary or missing), please feel free to tell me I'm a dumba$$. On another thread someone suggested leaving 4th synchro and dog teeth alone since there's not much action compared to the other gears, any thoughts (would save me a couple hundred bucks)?

Part Name Part #s from PET
Case
Gear Housing to Trans Case Gasket 930 301 191 00
Trans cover to gear housing gasket 930 301 351 00
Inspection cover gasket 915 303 225 00
Ground Strap 999 611 920 20

Drive Shaft
Collar nut 930 302 451 00
Synchronizer ring 3rd & 4th gear (2) 930 302 303 00
Shift sleeve (AKA slider) 3rd/4th 911 302 411 20

Pinion Shaft
Synchronizer ring 1st & 2nd (2) 930 302 301 00
Shift sleeve (AKA slider) 1st/2nd 930 302 411 00
Collar nut 930 302 453 00

Dogteeth
Synchro Hub 1st symmetrical 930 302 241 03
Synchro Hub 2nd 930 302 242 00
Synchro Hub 3rd & 4th (2) 930 302 243 00

Tools
Synchro Hub Removal Tool 930 1st & 2nd P224
Synchro Hub Removal Tool 930 3rd & 4th P223

Brake Bands/stops
Stone 1st/2nd gear (2) 930 302 315 00
Double barricade tape 1st gear 928 302 319 08
Stop 1st gear 928 302 320 01
Brake band 2nd gear (2) 915 302 316 01
Stop 2nd gear 930 302 321 00
Brake band 3rd/4th (4) 911 302 316 00
Stone 3rd/4th gear (2) 930 302 325 00
Stop 3rd/4th gear (2) 911 302 317 01

[jwasbury]

Good on you for rolling up the sleeves and taking this on DIY style.

I've read (or been told) that a transmission overhaul on these cars is lower on the difficulty scale than an engine overhaul. And I while I've had my hands in several engine overhaul projects including my own, that transmission still mystifies me and I must admit I have a hard time accepting that it's an easier thing to work on.

Big respect, and let's see some pictures of blood and guts. We will cheer you on.

[Oheggem]

Originally Posted by jwasbury

that transmission still mystifies me and I must admit I have a hard time accepting that it's an easier thing to work on.

I think the exact same thing. I can`t see how the tranny works like a can with an engine. So the thought of just opening up a tranny frightens me. Also i can`t find really good DIY picture guides or any 3d videos on how the tranny operates.

[infraredcalvin]

I'm in the same boat, Oheggem, I agree, spent countless hrs trying to find just that, I like to know how things work before tearing into them, although I'm getting a better idea just trying to research the parts, the workshop manual and PET have been helpful. My goal is to take a lot of pics and provide a little more of a step by step...

So there will either be a good guide to a 930 trans rebuild, or a nice documentation of the destruction of my box!

Jwas, seeing some of your posts has inspired me to dig in. I appreciate the support!

Krasusky, MAN UP! And drop her panties! J/K. I'm thankful to have access to a lift it make it so much easier to raise the car while the engine is on a dolly. I'm also a 914 guy, Ive dropped her engine who knows how many times, always by myself, so I'm no virgin...

I must admit, hands down the 930 drop was/is easier than the 914-4 drop. Less to disconnect, and a little more room to do it... Although 2x as heavy!

[aseem]

I'm glad I did my transmission myself, even though I ended up braking it. It was rewarding, although costly...

Based on your list, I think you're probably replacing more parts than neccessary. I did the same thing, but to a lesser extent.

My advice is as follows:
- Take your time, take lots of pictures, and note exactly which way things are comming off.
- Inspect all bearings, and replace if in doubt. I suspect the needle bearings under the free gears caused mine to seize
- Keep your workplace and parts clean
- Ask this forum for advice, but post picture and progress. This is the best way to get feedback from the crowd. I don't think I could have done it without PP forum
- Make it a point to understand how everything is working. I sat down and studied the syncro mesh for hours. Its a cool design that porsche sold to a lot of manufacturers

Good luck, its a fun and rewarding project.

[infraredcalvin]

Arnljot, I was hoping you'd chime in with some words of wisdom (and encouragement), your posts were the inspiration for this project, although the end scared me. I ordered all the parts last night, a lot were special order for the 76 gearbox. This will be a slow and steady project as I don't get much time to work on the car between family & work. Thanks!

[Matt Monson]

I think you have figured this out but all of the asymmetrical updates to 1st that were done to the later gearboxes can be done to your 1st gear teeth and slider.
The important thing is to keep them matched. Just make sure whatever replacement teeth you choose you get a 1-2 slider that matches, symmetrically or asymmetrically.

The debate which design is better is never ending. Either will work.

[aseem]

Originally Posted by infraredcalvin

Arnljot, I was hoping you'd chime in with some words of wisdom (and encouragement), your posts were the inspiration for this project, although the end scared me. I ordered all the parts last night, a lot were special order for the 76 gearbox. This will be a slow and steady project as I don't get much time to work on the car between family & work. Thanks!

Only too happy to be of some help, and glad that my transmission project can inspire others. I've had some PM's over the years abouth this topic, and I always encourage people to do the transmission them selves. As I said, its very awarding. I read through all of my transmission threads yesterday after reading your post. I must admit, it was a bit emotional. LOL

I'm an engineer (computers), so understanding how stuff works has always triggered me, and I think that is why I enjoyed the project so much. shait happens, and that's when the learning really begins. So on that note, I attach this page from Paul Frére’s “Porsche 911 Story” where he explains the Porsche syncro mesh. It is a neat design, much better engineered than comparable designs from Borg-Warner. But more expensive, and somewhat harder to shift. However, when you study the design, you realize that the mechanism strives to syncronize the speeds of the two gears, and that the harder you work your shift lever before they are synchronized, the harder the syncro mesh will oppose the force.

Please let me know if I can help you in any way during your project. I will follow your thread, and provide moral support underway. Good luck and have fun.

[infraredcalvin]

Waiting for parts, but it's amazing what a toothbrush and a power washer can do to the case...


In the mean time I was noticing what looks to be all of 38 years of dirt and grime on my motor, so I popped the valve covers to see...
76 930 3.0 engine rebuild, where to start?
Here we go, down a very slippery slope...

[infraredcalvin]

Originally Posted by Matt Monson

I think you have figured this out but all of the asymmetrical updates to 1st that were done to the later gearboxes can be done to your 1st gear teeth and slider.
The important thing is to keep them matched. Just make sure whatever replacement teeth you choose you get a 1-2 slider that matches, symmetrically or asymmetrically.

The debate which design is better is never ending. Either will work.

Thanks for clarifying, I found some info that vaguely suggests that.

In my parts search and subsequent purchase I was sent the following that I'd like to verify are corresponding shift sleeves and dog teeth as mentioned above:

930.302.411.02 - 1-2 shift sleeve
930.302.241.03 - symmetrical 1st gear dog teeth

I'm not sure but it looks like I might have the asymmetrical sleeve and the symmetrical dog teeth. I'm waiting on parts supplier to get back to me.

[infraredcalvin]

I think I just answered my question (I stole the pics from aseem's thread).

Asymmetrical dog teeth



Asymmetrical shift sleeve:



Please confirm???

[infraredcalvin]

Here are the parts I received:

1st gear dog teeth (symmetrical):



2nd gear dog teeth:



1/2 slider (asymmetrical):



Looks like I'm waiting for more parts...

[Matt Monson]

Yep. You want to get the asym teeth for first.

[infraredcalvin]

Ok, parts received, gears removed - BEWARE using the SIR tools P224 & P225, if you use them as they are designed to fit they are prone to failure, then you'll be stuck halfway through your disassembly and fighting with Mister Sir himself (who by the way has never actually used these tools before, but has extensive notes ) to replace the broken tool. More on that later, still not resolved BTW...

Moving on, big question for the rebuild gurus, what sealant to use on the housing with the paper gaskets. Previously someone had used what looks like a dark red or purplish red sealant. My box did not leak before, I would like it to be leak free again...

Thanks in advance!

[paganrj]

Infraredcalvin,
Are you done with your gearbox repair? Were you able to find the 36mm pinion collar nut? I am trying to complete my repair but I can't find that nut (930-302-453.00) anywhere. Any suggestions?
Thanks!

[infraredcalvin]

Ha I guess I dropped the ball on fininishing this thread, but yes she's all buttoned up, new hardware except that damn collar nut, I had to reuse, even tried to have the dealer special order from porsche... No luck. There were a few places that said they had it and allowed me to order, but they had to call back and refund due to NLA. Try reaching out to Matt Monson who posted earlier, he may have a source, and he's a nice guy to boot. I got frustrated and didn't think to do that until after she was all buttoned up.

Good luck!