Brake troubles - soft pedal

[DaleS]

OK, so this buddy of mine... no, really; his name is Gary and he's not imaginary! He claims that his '81 X (he's owned her since new - nice car) has always lost brake pedal if he uses her hard or even if the car sits for a couple months without use.

Obviously, over the 30 years of ownership, he has replaced master cylinder, calipers, etc. but they still go mushy on him with use. We did a track day last Sunday and his pedal went soft in the third run. He claims he can bleed them (he says he gets some air) to bring them back up to par but I've not seen an X do this. Has anyone fixed a similar issue?

 

[wannabfast]

well since you are tracking the car, i would suspect air is getting in the supply hoses due to heavy cornering, hence why most cars now have a reservoir directly on top of the master cylinder

also the brake hoses may need some attention, but the supply hoses may be cracked allowing for air to seep in, causing your issues

 

[TonyK]

Heat.

This year at FFO 2010 on the Tail of the Dragon Run I started getting a mushy pedal. I found that the right front caliper was dragging ever so slightly. I even put the car up on the hoist and checked all the brakes before the trip to North Carolina. With 500 degree silicone oil in the system it began to boil to the point that I had no brakes at all. I suspect that the issue here too could be a slightly stuck caliper causing over heating of the brake fluid.

TonyK.

Grimsby Ontario Canada.

 

[Dan Sarandrea (Phila)]

Hey Tony, that's a notable factoid considering that the last time I saw the underside of your car at FFO '09, I noticed you had fitted some brake cooling ductwork...:hmm:

 

[TonyK]

Well now.

You are correct about the duct work and I really wish I would have repaired or replaced the torn hose under the car body, but I thought, will I need it? Of course I did, and I didn't have it. What luck.

TonyK.

Grimsby Ontario Canada.