72 input shaft seal leak
 

How hard is it to replace the input shaft seal? Mine is a 72 with the seal behind the housing which means the transmission must be disassembled . Is this an easy job for a DIYer? I have rebuilt my 911 engine but never tackled a 915 transmission. Are special tools required? Thanks!


Kevin
72 911T/E

Last spring I did my '72 transmission rebuild with the help of a very 915 savy friend. My seal leaked the first time I drove the car after rebuild. I pulled the engine/trans and had a professional in town put the seal in, and it leaked once again! The third time out, the professional wrench got it right. My advice is go with a professional. YMMV. The 72 915 have some beautiful brass cages for the roller bearings, something the later years did not use. Replace all you syncro rings and dogteeth while you are in there.
I do not know why we had so much trouble getting the in right.

Bill

Not easy as the transmission has to be partially disassembled (shafts need to come out). Not counting R&R of engine and transmission from car probably around 6 to 10 hours is required for an experienced mechanic with the right tools to do this task. I would plan on 2 to 3 times this long the first time. If you've rebuilt a 911 engine this seal replacement is within your capability. To get to the seal and back you'll need common hand tools and metric wrenches plus a 36 mm socket, a torque wrench capable of reaching 180 ft-lbs, the P360a plate or template to set selector fork rods (some manage to not need this by not disturbing the set-up) and stuff (PVC pipe and fittings) to make pushers to remove and replace the seal. A hydraulic shop press is very handy as is an engine stand adapted to hold transmission. Besides the seal in question you'll at least need the paper gaskets (I'd get the entire gasket and seal kit and replace everything), some new lockwashers for the bearing retainer plates and replacement transmission oil (Swepco). If you take the shafts apart (to replace synchros, dogteeth, etc.) you'll need more time and tools. Cheers, Jim

Thanks guys, Thank God my trans has been rebuilt 3 years ago and this same leak was repaired 2 years ago by the same shop. Well here it is again. What's a fair $$$ for replacing this seal? Is Swepco gear lube red?


Kevin
72 911T/E

I would be suprised to see a good Porsche shop do this job for less than $500 not counting the engine R & R. I would also check the input shaft for runout and to see if it is worn where the seal runs. Swepco is blue colored. Jim

Jim, any idea what brand the red oil might be?Thanks!


Kevin

There is no reason that makes sense ... to assume a certain colored gear oil is one brand or another!!!

Swepco 201 SAE 90 gear oil is golden brown.

Swepco 201 80W-90 gear oil is blue.

Swepco 210 85W-140 gear oil is dark reddish-brown.

Swepco 212 85W-140 gear oil is greenish/grayish golden brown.

<b>There are several other brand products out there you may find in your 915 that are red!!!</b>

As Jim posted. $500 is about right. What I don't understand is why two years later it is leaking again. Makes me wonder about the shop that did the rebuild.

Yes, it was foolish to assume Swepco is always blue. I was thinking though of Swepco 201 80W90 which is blue and is commonly used with good results in 915 tranmsissions. Cheers, Jim

The red stuff is probably Redline. It's at least a SWEPCO equivalent...if not a bit better.

Like Jim mentioned, I would check the input shafts surface where the seal rides. Make sure its smooth and there is no runout with this shaft. Also, splined parts love to tear seals upon installation.

I replaced this very seal in a 74 915 w/out removing the input shaft. I just removed the diff and made some installation tools and no leaks. Removing the diff requires no set-up tools, just replace the o-ring on the diff cover plate.

Good luck.

Chris