Sunday, February 1, 2009

Firewall Gooooo! and pack those bearings...

A cracked firewall? Whoever heard of such a thing on anything newer than a De Dion Bouton? Uh, Porsche 944 and 968 owners. That's who.

It seems if you have a perfectly bled clutch and the feel still a bit on the pudding side, you probably have a cracked firewall. It is made of metal thinner than parchment paper and it gives way. 

One can of course, take everything out, weld in a good firewall section from a donor and bolt it all back up. But in many cases that is overkill. It is a hydraulic clutch and it does not have that much torque on it in use. So, I thought I would try a patch I found online to see if it worked. If it didn't, I would waste $5 and a couple of house.

The only reason the job is hard is there is some garbage in the way. Emissions stuff. And in my case, the wires from the firewall were wedged in the way of the bolt. The arrow is pointing to these wires. So, I had to loosen the brake booster from the inside, and was then able to get the wires out.

In image two, you can now see the 13mm bolt that bracket will attach to.

In the third image, you can see the templates I made to figure out the shape and size of the metal. I made a few from cardboard so I would not have to keep making them as they tore.

In the fourth image you can see the 1/8th in steel that I bent into place. I bolted it to the clutch master, and then, once it was tight, drilled the hole through the forward end of the bracket and the chassis.

In the fifth image, you can see it in place.

Tested, it worked a charm. There is no visible flexing or bulging of the firewall. And it lets me put my money into other places for now. Even if this bracket wears out, I made up another while I was at it to have a spare at hand. And the clutch pedal feels so smooth and solid now. 

In the sixth, you can see that I also repacked my front wheel bearings. As this was a last minute project I was glad that my local parts store had the requisite seals to do the job. 


Ben said...

Great blog! I've linked it from my blog,
I'm also reading your 901 book. Just got introduced to that greasy bastard, Patrick Patrick.

I found your blog from the Rennlist 944 forum.

Kevin Gosselin said...

Ben. Thanks for the 2x support.