Brake failure - Pedal to floor.

[marcus mcgee]

On my trip to Chi town I got caught in heavy traffic on 90 in the middle
of Chicago. Lots of slow stop and go and people pulling across 3 to 5
lanes and always in front of me. Used the pedal alot. On one stop the
pedal kept going down and no stopping (big brown spot on seat). This
happened 3 or 4 times and if I pummped some they came up. Brake light
came on and I could not pul over. Went through a toll booth and got up
to speed and brakes came back to top. No further problems after that or
before that.
Tried 4 panic stops on the way back and everything worked fine withy a
firm solid pedal. Checked fluid and it is clean and full. It was a
very hot day but brakes were fine before and after.

ANY IDEAS AS TO WHY AND WHAT TO FIX?

Marcus

 

[thomas g. warner]

sounds like moisture in you brake fluid. the heat got high enough in stop
and go to make it boil causing gas. Only thing I can think of.

>On my trip to Chi town I got caught in heavy traffic on 90 in the middle
>of Chicago. Lots of slow stop and go and people pulling across 3 to 5
>lanes and always in front of me. Used the pedal alot. On one stop the
>pedal kept going down and no stopping (big brown spot on seat). This
>happened 3 or 4 times and if I pummped some they came up. Brake light
>came on and I could not pul over. Went through a toll booth and got up
>to speed and brakes came back to top. No further problems after that or
>before that.
>Tried 4 panic stops on the way back and everything worked fine withy a
>firm solid pedal. Checked fluid and it is clean and full. It was a
>very hot day but brakes were fine before and after.
>
>ANY IDEAS AS TO WHY AND WHAT TO FIX?
>
>Marcus
>
>
>

 

[mark grady]

Matches my experience coming down Ober Gatlinburg mountain last fall.

As Tom Warner indicates, I'd also suggest that you've got moisture
contamination, and a fairly serious case of it to boot.

Have you ever had your brake system flushed and new fluid installed? If not,
you should consider getting it done. Word of advice from one who has...

Never push the brake pedal all the way to the end of its stroke while
bleeding your brakes.

Chances are very good you will tear the master cylinder piston cups and then
have to get a new master cylinder or re-build the one you have.

I think when you flush your fluid, you'll be very surprised at how bad it
looks when it comes out. I know I was! That little bit of clean clear stuff
in the master cylinder was the only brake fluid that wasn't dirty
brown/black.

Mark

PS - If you don't get your brakes flushed, consider getting really good
insurance and Depends adult undergarments.

| -----Original Message-----
| From: owner-gmcmotorhome
| [mailtowner-gmcmotorhome]On Behalf Of Marcus McGee
| Sent: Friday, July 30, 1999 10:08 AM
| To: gmcmotorhome
| Subject: GMC: Brake failure - Pedal to floor.
|
|
| On my trip to Chi town I got caught in heavy traffic on 90 in the middle
| of Chicago. Lots of slow stop and go and people pulling across 3 to 5
| lanes and always in front of me. Used the pedal alot. On one stop the
| pedal kept going down and no stopping (big brown spot on seat). This
| happened 3 or 4 times and if I pummped some they came up. Brake light
| came on and I could not pul over. Went through a toll booth and got up
| to speed and brakes came back to top. No further problems after that or
| before that.
| Tried 4 panic stops on the way back and everything worked fine withy a
| firm solid pedal. Checked fluid and it is clean and full. It was a
| very hot day but brakes were fine before and after.
|
| ANY IDEAS AS TO WHY AND WHAT TO FIX?
|
| Marcus
|