Sunday, May 15, 2011

Getting reacquainted with the front brakes

It's been many years since I've done a front brake job on an old VW. The last time the front brakes were done on this car was about 12 years ago, when NOS wheel cylinders were installed by a local mechanic. Initially I thought I'd be able to get away with a brake fluid flush and adjustment, but the right front brakes were locking up. Stuck wheel cylinder(s)? Collapsed brake hose? The car has probably only seen 1000 miles since the brakes were done so how bad could things be?

I was stopped in my tracks soon after starting by an odd thing: Both lock nuts turned together when I tried to loosen the outer one on the right side. That shouldn't happen. I didn't have a thin 24mm wrench so had to source one. Luckily Lanner Kahn at VDUBEngineering in Canada offers a nice purpose-made 24/27mm spindle wrench, so I ordered one up. Once I got things apart the problem was obvious. Someone had used a larger diameter lock plate from another VW. This is the kind of hackery that can cause you to lose a wheel on the road. Not only that, all the expendable parts were shot—bearings, seals, the whole lot. Luckily, with a little help from Bill and Steve's, I was able to find everything I needed to put things right. Here are the old and new parts for comparison—it's as if the last bearing repack was done using only a crow bar and a sledge hammer. Nothing like seeing someone else's shoddy work to remind you that you're better off doing it yourself!

Turned out it was the wheel cylinders that were the braking problem -- gummed up from lack of use. I cleaned and honed them and I think they'll be all right for awhile, though I'm going to start searching for another complete set of NOS front cylinders just in case.


Paul Colbert said...

Have you thought of going to DOT 5 fluid since it looks like you are tearing it all apart? Paul

Scott said...

Hi Paul. I have thought about it but I've had less than satisfactory experiences with DOT 5 in the past. But then again maybe it was because I relied on others to do the work, and there's plenty of evidence now that their work wasn't very good. My understanding is that DOT 5 only really works well when all brake parts and lines are new or reconditioned. Flushing the system isn't really enough. True?