Even MORE gearbox trouble: any ideas please?

[911hillclimber]

My 73T has a 3.2 in it with it's box, both 1985.

The gearbox which was oil tight but noisy 2nd speed has just had a £3200 rebuild by a specialist in this field.

The box was supplied loose.

Returned after another screw-up by another reputable specialist, the box did a journey to see Mike's RSR, 201 miles and I had a pool of gearbox oil under the bell housing about 8" in diameter and dripping.

Re-builder said he was sorry I had this problem.

I took the box out after 201 miles and found the seal to have a pronounced flat on the lip of the input shaft seal. The shaft journal where the seal runs is stained black round the diameter. It will not come off with thinners.

The specialist sent me a new seal which I fitted last week and after a test drive of 50 miles the box is leaking in the same place.

I can only conclude the input shaft is scored though it felt totally smooth to the touch and free of radial scoring.

I now need help before I throw the car away and leave the Porsche world forever.

1
How DIY is removing the input shaft alone and would I need any special tools to get it out and reset the forks(etc)?
I have rebuilt Porsche engines etc so not too bad with a spanner.
From the cross section diagram in the Haynes manual i should be able to leave the pinion/diff shimming alone?

2
With the shaft out and presumably it is scored how to rectify the damage?

I thought of metal spray the journal and have it ground back to diameter.
Get another one that might be ok, but would need first gear too?
Get a new one. How much would that be?

3
If I chicken out and get the box to another specialist, anyone recommend me someone?

[stuby]

Sent you a PM

Stu

[haasad]

These little problems are what make classic car ownership so involving and certainly aren't exclusive to Porsche. After fault finding my ignition yesterday I helped with a TVR Tuscan racer with seemingly endless cooling issues the owner must be doing his crust and next to it was a 70's vette with its gearbox in a million pieces not to mention the 105 alfa that hasn't turned a wheel in anger yet. At least folks like you and I can DIY

Metal spray and grind is common for bearing and seal surface reclamation and gives great results if done properly. I'd be surprised if it was the shaft if its truly smooth and at full diameter. What was the seal tension like after you got it onto the diameter?, did it have a spring collar and if so is it still there, are you sure the seal lip wasn't damaged during installation the clutch splines are quite sharp? Did you get the "black stain" off before reassembling. Is the shaft concentric with the seal bore and straight? And was the replacement seal seated true and square in its bore
All obvious but necessary to establish.

Keep at it

Andy

[911hillclimber]

Hello Andy:

I am sure you are right, race car fall apart all the time as with my Lola.....

I think I've had enough of Porsche Classic Car ownership. I am sick to death of taking this box out.in.out almost every weekend.

The box was oil tight before it came apart for a slightly crunching 2nd.
£3200 later...
It is now leaking.

To the seal questions:

The box had a new seal fitted during the rebuild. After 201 miles it had a 2mm land on the 'lip' very noticeable with a new one to compare it to.
The gearbox is the later 915 so has the seal in a separate tube (thank god).

The seal had its tension spring and was in the right way round.
The tube itself has a smaller diameter form inside the tube into which you drift the seal. The seal was full in the smaller dia 'collar'.
The tube itself is sealed to the box case using a thin diameter O ring which is present.

The seal I have installed is a porsche part, in the right place and the right way round. I ran masking tape onto the input shaft spline, wetted it with gearbox oil and slid the tube with seal over and along the spline rotating it as it went along.
The seal and shaft journal were wet with oil when everything when fully home. The new seal had a new tension spring.

To the black mark:
I could not chemically remove it, carb cleaner or cellulose thinners had no effect.
I was reluctant to abrade the surface risking an uneven surface (it is not the most accessible part of the box.)

The only thing I can think of now is to strip the box to get that journal right.
I obviously feel well naffed-off having paid a fortune for this to happen.

[Bootsy]

I'm sure if you discussed it with the specialist on the phone you'd come to a better plan of action. Or maybe you've spoken to them already?

[911hillclimber]

Via emails yes.
Had a new seal sent down to me for me to fit.

Did that and still leaks. It must be the shaft that is damaged, but the box was dry before the rebuild.
Hard to keep any enthusiasm with this adventure and the 3 years of porsche related adventures in the Lola.

Quite fancy a Spitfire 1500 and join the National Trust. Far more sensible.

Rebuilt gearbox and overdrive = £495, Rebuilt Diff = £295, 911 = £3200
Rebuilt engine long block £500 911 = £4500
etc.

[Bootsy]

I'd give him a call and discuss your current issues and I'm sure youll find a solution with him

[hukent]

Try Dom Delany at S.V.P. he's not too far from you.

[911hillclimber]

Indeed very close to me!
Thanks.
I try not to use specialists if I can help it, only surrendering due to tools needed that I don't have or special knowledge etc.
I'll see what unfolds this week.

It is best the car sits in the garage as the hillclimb season starts next weekend which is why this is all so frustrating. I had hoped this would all be done before that circus kicked-off as well.

I'm booked in for the big Silverstone weekend, so hope to get things sorted before then.

[haasad]

[quote="Bootsy"]I'd give him a call and discuss your current issues and I'm sure youll find a solution with him[/quote]

Deffo' the very first thing to do.

Andy

[johnM]

I can not believe that a thread like this will help the situation.

I can understand your frustration but why go to the trouble of writing this thread when you could pick the phone up and actually speak to the man. I am sure he will do everything he can to resolve this problem.

Kind regards.

[911hillclimber]

The threads purpose is clear:
I asked for help on 3 questions.
I gave the back ground to the issue to detail things.

[johnM]

The threads purpose is clear:
I asked for help on 3 questions.
I gave the back ground to the issue so I hope to detail things, and yes, I'm naffed off for the reasons I've given.

And with regards to question 1 & 2 am am sure a gearbox specialist would be able to answer them questions better than anyone else.

[Bootsy]

My thoughts John which was kind of my point with my previous 2 posts. Have a chat with him and I'm sure you'll find an agreeable solution

[911hillclimber]

I will let you know!

Over the last 4 years I've have nothing but grief from all quarters, and I always expect the worst out-come, I'm rarely wrong.
Maybe this time will be the exception.