replacing shift seal on 915

nocones · 04:23 PM

The seal around the shift shaft (correct term?) leaks on my 915. I ordered and recieved a new one from Pelican but I am unsure on how to install it. Can I remove the old and install the new seal from the outside? or do I need to remove the cover and do it from within?

Thanks!

slammed1000 · 01-13-2007, 05:07 PM

you will have to install the seal through the inside cover. i think i ended up dropping the trans mount to gain enough access when i had to remove it. you will have to take the coupler out. i made a seal driver out of a piece of pvc conduit to drive it in.( i could ajust the size of the driver by cutting it to get the most swing out of the hammer this way)

Early_S_Man · 01-13-2007, 06:18 PM

Here is a Pelican tech article showing/telling how to replace the seal with the transaxle in the car:

http://www.pelicanparts.com/techarticles/mult_shifter_rod_seal/mult_shifter_rod_seal.htm

nocones · 01-13-2007, 07:37 PM

Thanks!

nocones · 02-03-2007, 03:32 PM

Now I'm confused...

I finally had time today to drain the transmission (it's already out of the car) and remove the old seal.
First off, as per the article linked above I was able to hook the old seal and extract it without removing the cover from the end of the trans.

Here's where I start to get confused.
The shift-shaft does not exit the hole in the trans cover in the center. With the trans sitting on end, shifter-end-up, the shaft is angled down slightly (toward the bottom of the trans). Is this normal, or should the shaft be centered?

Also, the article above notes to install the new seal with the metal ring out. This is the reverse of how the original was installed. The photo in the tech article looks like the seal is installed with the rubber out also.

Any help here is appreciated.

nocones · 02-03-2007, 06:47 PM

Anybody? Bueller...

nocones · 02-05-2007, 07:59 AM

I'm fairly certain that the seal should go "spring in".

Still would appreciate any feed back on the shaft angle though.

Monday bumparoonie.

PhatA55 · PhatA55's Garage

On a seal the spring always points toward the fluid you are trying to contain.

Walt Fricke · 10:03 AM

Mark answered question 1. Someone put that seal in backwards. That might have had something to do with the leak also, though that is not, I think, a highly stressed seal (compare the flywheel seal, rotating at 6,000 rpm with 60 psi oil wanting to get by it).

Question 2: I gather that your shaft does not appear to be concentric with the hole it goes into? Your photo shows it angled down (if the tranny were in the car).

Well, it should be centered as you supposed, for the reasons you had: how can the seal seal otherwise.

First guess: that shift shaft is bent. Remember the advice to disconnect the shift coupler before trying to take the transmission (most often attached to the engine) out? Maybe the guy who put the seal in wrong forgot about the coupler when dropping the rear of the engine so he could back things out. If he lowered it way down (or something slipped off a jack), that might bend the shaft down. The shaft isn't feeble (I often rest that end of the assembly on the shaft sticking into the chassis hole), but if constrained it can bend.

You can verify this by shifting by hand and watching what happens as you rotate it and shoving it in.

Anyway, a bent shaft also ties in with the leak, backward seal or no.

Walt Fricke

nocones · 02-05-2007, 10:02 AM

Thanks Mark.
That was my instinct on the seal and I had it confirmed by a mechanic friend this weekend.
The above tech article states the opposite. Perhaps an edit is in order?

Still hoping someone with more 915 experience than me can comment on the shaft position...

Walt Fricke · 10:11 AM

And, on reflection, replacing a bent shaft may be a big job. I can't quite remember if you can get it out without pulling the middle part of the case off of the differential end (the nose piece has to come off no matter what unless you try to whack it straight in place). Pull the 4 bolt shift guide plate to free the dongle, but will the dongle fold up and fit through the large passage?

Walt

aldente295 · aldente295's Garage

I'll be tackling this seal tonight, and I'm still a wee bit confused on which way the spring on the seal should be facing. The tech article has a comment at the bottom, and Wayne himself has come back to confirm that the article is correct:

Comments: great article, very helpfull, however, are you sure the ring on the seal should be facing out? i thought the ring in the grove serves the purpose of stopping the oil...
just a thought, regards,
September 14, 2009
Followup from the Pelican Staff: On other applications, yes. But there's no oil involved here. - Wayne at Pelican Parts

Normally I wouldn't question Wayne...