Sheng

Just looking for some help on separating a part of the transmission

I have included some pictures that show which transmission it is (it is out of a 95 C4)



This picture shows the damage


Finally the red line shows where I am trying to separate it.


I am just trying to figure out if there are any special steps required to taking it apart.

Regards,
Sheng

Pete Debusmann

A good welder can fix that without you taking it apart. If you want to take it off you need to completely disassemble the tranny. You start by removing the rear cover.

Pete

Sheng

Are there any special tools required for removal?

Pete Debusmann

Yes there are.

There is a locking tool to hold the input shaft so you can get the big nut off the other end of it (under the rear cover). You also need some really long pullers to get some of the gear clusters off of the shafts.

Pete

Pete Debusmann

Why do you want to take it apart. If you plan on replacing the diff housing due to the crack then you will need some very special tools to set the pinion depth when you put it back together.

Pete

Sheng

The welder recommended that it be taken apart, then welded and finally machined. Just trying to get the process and the tools required for the job. Unfortunately, welding the piece as is, is not available

Thanks for the insight so far Pete!

bobt993

As Pete mentioned you need some special tools and a ton of experience on G50's to avoid getting it back together incorrectly. Your best bet would a salvage bell housing and sending it to an experienced rebuilder who will adjust and inspect everything before it comes back to you. If your going to remove the damaged area you have to start at the tail and basically take the entire trans apart. There are several tricks that are easily missed Chris Cervelli is really good at these and he is in Denver CO area. You can also check with GT Gears on this forum for a shop closer to your location.

Pict 1 is the first section. Gears must be pulled to continue.
Pict 2 is the second section where most of the fun is. You can remove the cluster almost complete as you work towards removing the mainshaft and gaining access to the bell housing.
Pict 3 is some of the gears and you must carefully place all the parts in an orderly layout for reinstall.

I did this with a 30 plus year experienced Porsche mechanic and have no interest in doing it again (and helper's mug shot in pict 2).

e3photo

The down side is that you are opening a can of worms.... the upside would be that close ratio gears can now be "while you are in there"

Sheng

This looks like a fun project to tackle... Thanks for the new pictures I'll use it for the tear down!

Garth S

I have ventured into the G64 trans as far as the main case - and knew enough to confirm that I didn't know enough to go further: here's the link that shows replacement of the intermediate case, which was the objective at the time.

Were I to face repair of the bell housing damage you have, I would first scribe and cut a piece of 1/4" aluminium plate to precisely fit the bolt holes and dowel pins on the engine ......... then bolt that plate tightly to the damaged bell housing: with the alignment secured, pull/tap the damaged areas back to 'spec', and have the welder do his best.

The area in question does not appear to have anything requiring critical alignment, so as long as the engine mating surface remains true, I would go for the welding as Pete D suggested.

matt777

I would be interested in knowing what an acceptable weld procedure was for this aluminum case. I know it can be successfully weld repaired. My concern is the required preheat which may require removing it. There was a post regarding transmission repairs and I thought the cost to dismantle and reassemble was around $1500-$2000 plus parts.

bobt993

I am sure Pete has been down that road. Really no different than having the ears repaired on the clutch fork shaft. Just make sure you have a good welder and cover up the axle flanges or put them back in place.