930 Gearbox Disassembly
 

Does anyone know a good way to break loose each of the nuts at end of the two shafts? They are torqued on very tightly. Is it safe to use a breaker bar on each to get the necessary leverage? Would an impact wrench be better than breaker bar? Here is a picture of the problem.

http://forums.pelicanparts.com/uploa...1124175360.jpg

I use an impact wrench to remove them...never damaged anything that way.

Thanks. Is there a good way to keep the shafts from spinning?

I use an old clutch disc, and I have a "clutch disc lock" that is just a plate, that is studded into the clutch, and through the engine/transmission mount holes. It's like a flywheel lock and works flawlessly.

Steve, I'm contemplating changing some gears in my 930 box. How difficult has it been for you? I figure I could send it to a shop to have them change to a lower geared R&P or I could change out some of the gears myself. Are there any critical shims or settings that need to be set when it goes back together? Can you leave the R&P intact and just change the gears? Thanks.

Changing the gears in a 930 trans is dead easy. You don't even need a press, just a gear puller with long arms. Possibly not even that. Removing the dog teeth from a gear is a pain for 2nd and easy for the other gears if you have the special tools and a press. If you are getting new gears or used gears with the dog teeth already removed you can install new dog teeth without special tools (but you'll still need a press).
I'd advise you to have a shop set up the R&P.
-Chris

Hey Chris, after our conversation on Sat regarding the same subject. I saw there is a tool for $125 if I recall specifically for the dog teeth on 1st and 2nd gear.. Would that make it a simple ( relatively) task? Seems we'd blow that much having a shop do it..
Todd

The "tool" only works for 1st on 930, at least with the stock 2nd gear.
-Chris

Hi David,
I'm not sure how difficult it is yet, but I think Chris' description of the process is accurate. Once the tranny is out it should go smoothly. I have a unique tool that will make reassembly and shift fork adjustment more accurate. I found a case where the guy milled out the side of it, thus exposing the shift forks and the entire gear set. I will post a picture of it tonight. It is in place of the shift fork alignment jig which is difficult to find for the 930. I think many guys do the job without jig or the cutout case. Since this is my first time working on a tranny I need all the help I can get.

Other than being dimensionally different, the 930 is pretty much like the 915. The shift fork alignmnent "tool" is just a flat plate with some holes in it. The holes are for the various shafts and rods that go through the end of the main case, so they simulate the case being in place.

The idea of a dummy full case piece is intriguing (a use for a case somehow damaged?), but seems overkill. You can, indeed, usually get by without this tool at all, because the shafts and rods are held firmly enough by their bearings/bushings located in the bulkhead between the gears and the ring and pinion, so they keep their alignment even when unsupported.

However, it should be pretty easy to make this tool out of a piece of wood. Use paper to trace where these openings are (some ingenuity required) and drill suitably sized holes in your wood piece.

Naturally, if you have some kind of tool available, why bother making one.

Walt Fricke

(who used the worn out clutch trick to hold the input shaft, then eventually disassembled a rubber centered clutch to get the splined part to weld onto some scrap steel and bolts to duplicate the factory shaft holder)

Walter,
What's your experience with removing the dog teeth from 2nd gear.
Irrationally Exuberant Chris say's it's all but impossible ( or expensive !! or both).

Chris,
http://www.pelicanparts.com/cgi-bin/ksearch/PEL_search.cgi?command=show_part_page&please_wait= N&make=POR&model=911M&section=TRANSM&page=2&bookma rk=4&part_number=PEL-TOL-P224
This clearly says 1st AND 2nd gear.. so who's right ?? you or Pelican??

Anyone have a picture of the dog teeth tool? I can usually make any tools I need at work.

It's not impossible, it's just that it's much harder than the other gears because the synchro hub removal tool doesn't work for 2nd. Perhaps there are some 930 2nd gears that have larger diameters so the tool would work with those? That's off my map of experience though.
BTW: My friend Palmer cuts off the 2nd gear dog teeth with his milling machine for me. It's good to have friends. :D
-Chris

SIR Tools makes the ones I have. Here is the one for "1st and 2nd" gear (that really only works for 1st):
http://forums.pelicanparts.com/uploa...1124216276.jpg

-Chris

9D

For the 915 tranny you need two dog teeth removal tools. The dog teeth have different IDs and ODs depending on the gear, but two covers the lot. Sounds like maybe the 930 second gear is an "oddball" for which the proper tool is not available? At least not at a reasonable price for DIY?

Milling the old out sounds fine - I have heard of people using a cutoff wheel on a Dremel to do much the same thing - break the compression forces so you can push the old off. As I recall, a less precise improvised tool can be used to press the new ring on.

But having the right tools sure is nice.

Walt Fricke

Here is a picture of the cutout case.
http://forums.pelicanparts.com/uploa...1124248342.jpg

Thanks for the pic Chris. After thinking about my gearing for weeks: R&P, change gears, or G50? I've decide to do nothing. I figure I'm making a big change with the engine and EFI so I might as well see where the power band is before I go and make gearing changes.

Wouldn't hurt to replace or at least flip some synchros and stone the burrs off the sliders. Don't need any fancy tools and the paper gaskets probably cost under $5 I bet. (The 3 for a 915 are about $1 each.)
-Chris

The tranny was shifting good when I pulled the engine. Another reason not to go into it is that this project is way over schedule so I'm trying to cut the scope back. With everything fresh and clean it should be easy to pull the engine and tranny and change gears a couple months after I get it running.

it's true that the tool does not work for 2nd gear. on 1st, the gear is larger than the toothed hub, so there is something to push against. on 2nd, they are the same size. i use a knife edged chisel and hammer to work the ring off. once you get it away from the gear a bit, you can pry it off the rest of the way with a larger tool. wear eye protection and clamp the gear crossways in a vise with soft jaws.

Sort of off the 930 topic, but raised in a response:

The paper tranny gaskets cost even less if you don't bother to use them. Loctite 574 (orange case sealer, anyway) works fine. I first learned this when I had to pull the shift fork guide cover plate, the gasket tore, I had no gasket, and needed to get things fixed and back so my wife could race the car the next day. That was the advice I got from a shop owner buddy I called in a panic. I liked this so much I did it with the larger mating faces as well on later transmission adventures. No more leaks than I had experienced with those flimsey paper gaskets, and no apparent significant dimensional changes either.

Walt Fricke
(915, not 930, experience)

So can someone give a list of the special tools that you need to do a 930 tranny right?

I'm sure JWW can chime in on this. But since I do my engines now, I may as well learn how to do my tranny too. My tranny is currently in the shop for a rebuild, and while I'm sure it will be a while before I will need those services again, I'd like to be prepared to tackle it myself next time.

Brian

Tools for 930 rebuild
 

Brian,

Here's a list of the 930 transmission tools off the top of my head.

synchro hub removal tools
These are thes only "special" tools. Pelican sells them.
1st gear tool PEL-TOL-P224
3rd/4th gear tool PEL-TOL-P223
You can get by without these rather expensive tools, they just make things much easier/quicker.
Note: These tools are weaker than there 915 equivalent. I found it necessary to heat the dog teeth in order to pull them off without damaging the tool.

gear puller You will need a puller with long arms. The one I use is made by Kukko, I have a 2nd set of longer arms (not pictured) that I use.
http://forums.pelicanparts.com/uploa...1124328894.jpg

hydraulic press to R&R the synchro hubs (aka dog teeth)

hope that helps
-Chris

Thanks Chris!

Brian

I know this is an old thread - but I'm pulling my 930 box apart at moment.
I did a 915 box a year or two ago, and recall locking the shafts in two different gears to hold the shafts from turning while taking the end nuts off.
Can't remember how I did it, but will it work for the 930 box - can't remember which gears I used - and there is an extra one in the 915.
Alan