teamking

I can't get out the brake booster.

As background, when I was driving back from VIR after the Chin event the first weekend in December, I figured I must have boiled my fluid because the brakes would stay on and slowly release after I had released the pedal.

Troubleshooting last weekend, I realized that the pedal itself was returning very slowly after I had moved my foot off it. So the brakes were doing exactly what you'd expect given the position of the pedal.

So, doing some searching here on Rennlist, I realized I had all the symptoms of a brake master cylinder that had very slowly leaked into the brake booster, and then the brake booster had gone bad.

Sure enough, when I got the brake master cylinder off, there was a pool of brake fluid in the bottom of the brake booster. Score another victory for Rennlist!

Anyway, getting the three nuts off the inside of the firewall was a pain, but I was prepared for that and it gave me an opportunity to clean more *heavy* insulation out of the footwell. Great!

But, I can't disconnect the freakin' shaft from the pedal. The pin is literally fused to the yoke. I've tried penetrating fluid, a hammer, trying to spin the pin by torquing it through the hole in the pin, no help.

So, I figured I'd do it the hard way, and just loosen the adjuster all the way until the shaft unthreaded from the yoke. The freakin' locking nut is fused to the freaking yoke, too!

I tried penetrating fluid on that as well. No luck.

So, then, I broke out the torch (which made me really uncomfortable working in that tight a space and the fumes and who knows what might catch on fire so I had my wife and daughter standing right outside the car with a wet towel and a bucket of water and I unpinned the fire system just in case) and heated the crap out of the pin and the yoke and the retaining nut and guess what... NOTHING WILL BREAK FREE!!!

I've got it soaking in more penetrating fluid.

I think the score right now is:
Rennlist: 1
Brake Booster: 3
Me: 0

Any ideas?

Mike C.

Holy smokes that's amazing it could have gotten that rusted!

teamking

OK... Score one for the penetrating fluid!

The locking nut finally broke free when I found a way to use a screwdriver jammed up into the yoke to provide counter-torque and I squeezed the the wrench and screwdriver together. Still managed to bust my knuckles when the nut finally gave way. Working in the footwell sucks!

Nevertheless, the brake booster remains.

I've got one more line to move out of the way (the clutch hard line) and I think I will be able to get it out.

It'll have to wait for tomorrow...

xsboost90

we had that on the dragon- i just sucked the fluid from the booster w/ a vac pump and put on a new MC. wala!

333pg333

Good to know. I'm looking at pulling the whole thing out to replace with a dual m/c setup. Reading your troubles made me start thinking the worst.

V2Rocket

seems like a good excuse to do a brake system delete. rotors and calipers x4 plus the lines, booster and master cylinder and fluid has to be approaching 100lbs.

scrub speed off by going sideways into turns


i agree though the booster is a bitch, did that a few years ago. tools didnt seem to work but brute force and four-letter words prevailed as always

teamking

Wish I'd done that six months ago when I first noticed abnormal brake fluid loss. I couldn't find a leak so I figured that the pads were just wearing quickly (I'd recently switched to PFC 97's) and that the fluid was dropping to compensate for the pad thickness loss. WRONG!

Just keep an eye out for the pedal not returning properly.

It's funny that I didn't notice it on the track. But when you think about it, you're supposed to be easing off the brakes slowly as you apply steering input. My brake booster was doing it for me!

teamking

OK, I just took a break for lunch and was complaining to my wife about how inadequate the Haynes directions for removing the brake booster are. As I was reading it aloud I glanced at the pictures and realized that the normally aspirated cars (on which the book is based) don't have the heat shield that forms a little "compartment" for the brake and clutch m/c's.

Can anyone with a turbo tell me if the booster can be removed without loosening/removing this shield?

It's days like these that I wonder why the turbo was ever built. It's just too much plumbing in too tight an area.

I really like driving it, but I HATE working on it!

teamking

Victory!

Loosened the two attachment on the top of the heat shield and had enough wiggle room to get the booster out!

Wow-- that was a PITA! 10 hours... to get it out.

Don't know if I'll be able to get the new one back in like this or not... I may end up taking the whole shield out anyway. I gotta replace the electric water pump that is mounted just to the outside of the shield anyway... so access will be MUCH easier if I can get it out.

Clutch m/c is coming out soon, too!

I really don't know what I would have done if I had been planning on keeping the a/c lines. I've been cutting them to get them out of the way. Adding lightness.

The rest of the a/c system will be coming out soon, too.

I've go a lot of work before this thing runs again!

TroyN

I'm in the same predicament except loosening the top bolts on the heat shield have not given me enough room to get the booster out. What did you end up doing??

Dino951

Bumping an old thread to obtain some advice. I am in the same predicament; the brake booster shaft pin is rusted to the yoke. Heat, PB Blaster, nothing is working thus far. I see that OP was able to loosen the lock nut and back the shaft out that way. I take it if I did it that way, I basically just leave the rusted pin in for life? Any advice? Suggestions?

Tiger03447

Glad to see this thread. Further, glad to see that the booster interior is accessible after the M/C is removed. I plan to replace my m/c since all the calipers are off, the brake and fuel lines removed, and the new M/C is near my foot as I type this. I have intended to suck any fluid out of the BB, but really didn't want to replace it. The engine is out of the car so it makes things a LOT easier..The clutch m/c and slave worked well prior to engine removal so will wait on that PITA until it fails...probably right after I reinstall the engine with the new clutch..and it's 3 times harder to access.

Tiger03447

Took off the M/C today and looked inside the booster..pristine..YAAAY~! but the outside is rusted pretty badly..gotta take it out and repaint/restore it. WIINT guess I'll do the clutch master as well...I might re-evaluate that once the booster is out..

tempest411

You can get a brand new booster for not too much money. I got mine from 944Online.