Help! Brake Questions

[TWJ]

I recently purchased a new set of flexible brake lines (from our host) to replace what I believe to be the original ones on my '72 T. I am doing it to, hopefully, fix my "sticky" brakes and improve performance, safety, etc. However I found other problems...

The rear chamber of the brake fluid reservoir was empty empty and after refilling it, it seemed to drain again overnight. Is this rear reservoir (the larger one) for the rear brakes or the front? What could be the probable cause of it leaking? Connecting hose to the master cylinder? Leaking Master Cylinder? Other? Strange thing is I don't see any puddle of fluid anywhere.

Comments? Questions? Help?

Thanks much

[KTL]

Trace the braided hose that comes out of the reservoir and which feeds the master cylinder with fluid. That brake fluid is going somewhere. Start looking around in the front trunk area and down below beneath the floorboard by the pedals. I bet you find a pool of brake fluid there.

And I feel for you brother, I just had the worst brake fluid spill I could ever imagine. The pressure bleeder hose split right at the reservoir and sprayed misted fluid all over the trunk, hood, windshield, fenders, driver floorboard, pedal cluster, firewall areas of my car. I spent at least 3 hours flushing every place with alcohol-based glass cleaner and I still have fluid dripping from the gas tank area and the front of the chassis......... bad news that brake fluid!

[911pcars]

Power brakes?

If there's no visible signs of leaking brake fluid, it's probably being sucked into the engine via the power brake diaphragm and the PB vacuum line. Check this out.

Sherwood

[KTL]

Sherwood,

It's a 72. Boosted power brakes weren't available on the 911 until '77, no?

[911pcars]

Originally Posted by KTL

Sherwood,

It's a 72. Boosted power brakes weren't available on the 911 until '77, no?

Then look inside the tunnel where the shift tube, brake, fuel lines reside. Once upon a time, I had a mysterious loss of brake fluid. Something wore a small hole in the solid brake line in the tunnel. It got to the point of the fluid finding the nearest opening before I could spot the leak.

Bad news. Replacing the brake line, as I recall, means dropping the drivetrain. Maybe extraction from the front is possible. It was a long time ago. Like changing my kid's 10,000 diapers, it's an event not to recall.

Others with more recent experience can chime in.

Sherwood

[TWJ]

Looks like KTL was correct...there was about 1/2 pint of brake flood around the pedal cluster. So any ideas what the likely culprit is here? Reservoir feed lines? Master cylinder?

Also, I know that brake flood destroys paint but is it corrosive or bad for any other surfaces, materials or finishes?

[911pcars]

Master cylinder. The rear seal is broken. This allows fluid to leak onto the pedal area and floor. BF is a great paint remover. You can flush with water (it's water soluable), use wet/dry shop vac, then figure out how to dry out the floor insulation if it hasn't separated from the floor pan already. Floor prep may be a necessary part of the job to prevent future corrosion.

This is better than a leaking tunnel line and a relatively common repair job.

Sherwood

[TWJ]

Thanks 911pcars & KTL!

I think that about 1/2 of projects like this is (for a lot if us) figuring out the problem. It's great to get to have a resource like this forum to allow you to focus on fixing it and getting back on the road.

TWJ