Fixing a pesky leak on the transmission shift fork cover

[Kemo]

I've been having a small leak at the shift fork cover on my 915. After researching, I figured I would give it the 'shotgun' approach and attempt the impossible: Make my own gasket out of slightly thicker material designed for use with oil as opposed to paper (or what seemed like paper). And...resurface my shift fork cover And...use a gasket sealant

so I went to O'reily's and got some gasket material:



went to harbour freight and got a punch kit:



drained the oil, removed the cover and was able to salvage the old gasket to use as a template. I soaked the paper gasket in brake cleaner to remove the transmission oil. it dried out quite nice and looked like i could reuse it if I wanted to.



I used the punch set and a box cutter to trim out the gasket



After double nutting the studs on the cover and removing the locator pins, I then laid out some wet/dry sandpaper at 180 grit (I think) and used the bench to flatten out the cover and remove some of the imperfections with WD40 as a lube.



before:


after:


so then i put it all back together with blue locktite and sprayed the side of the new gasket that will be touching the cover with K&W Copper Spray.



here it is ready to re-install:



Its been 24hrs with no drips runs or seepage. I hope this helps anyone out with an annoying leak from this area. I do have some concern as the gasket material is roughly 3x as thick as the paper that i pulled out, id want to say 1/32th of an inch? Probably not an issue.

[Flat6pac]

The usual problem with the inspection plate is the fork coming loose, making gear selection very difficult.
A major builder of 901/911/915 suggest once the fork is found loose, replace the piece because the studs will no longer hold.
Bruce

[Bob Kontak]

Originally Posted by Kemo

I do have some concern as the gasket material is roughly 3x as thick as the paper that i pulled out, id want to say 1/32th of an inch? Probably not an issue.

Nice job.

Just keep an eye on it after you have run it a while and advise.

Operational heat will be the real test.

[pete3799]

I made a gasket for mine 3 or 4 years ago. Put it on dry and have had no trouble with it.

[Kemo]

Originally Posted by Bob Kontak

Operational heat will be the real test.

I will be exercising the new gasket at Texas World Speedway this weekend. Will update afterwards. Just had a Giken OS Limited Slip installed along with a full rebuild, so kinda giddy right now. Looking forward to some track time...

[KTL]

Originally Posted by Flat6pac

The usual problem with the inspection plate is the fork coming loose, making gear selection very difficult.
A major builder of 901/911/915 suggest once the fork is found loose, replace the piece because the studs will no longer hold.
Bruce

Agreed with Bruce and the solution to that is thru-bolt the cover plate like this

third gear squeal


Or just get a new billet piece from CMS or WEVO. A bit spendy, but nice parts and nice guys to deal with.

Go easy on the refreshed trans.!

[gtc]

A friend of mine had his shift fork come loose. I took it out and applied some Loctite 574 between the fork and the cover plate, since 574 is supposed to have good shear strength. Sealed it up with a factory gasket and threebond, and it's been good ever since.
Knock on wood.

[Bob Kontak]

Originally Posted by Kemo

I will be exercising the new gasket at Texas World Speedway this weekend. Will update afterwards.

Does Danny Ochoa still run his white 911 there? Last I saw him was late 90's running at TWS.

We worked together in the exciting world of bean counting.