Pontiac Repair: Brake master cylinder, e mail address, chevy lumina

Question
QUESTION: To: donotreply@allexperts.com
From: hniekoop@scarlet.nl

Re: Brake master cylinder Delco Moraine Powermaster ABS III

Model year 1989 -  2,8 l engine - 85000 miles.

This ABS brake master cylinder was installed in GM "W" cars (Pontiac, Buick, Oldsmobile) from the model year '89 through '91; also in Chevy Lumina 1990 and '91.

Hi Todd,
I reviewed your answer to my previous question and I have some additional information, namely:

With the ignition "OFF", the rear wheels of this car do not brake at all.
When the ignition is turned to "ON", the brake on these rear wheels hold perfectly.
The front wheels brake properly with ignition "ON" and "OFF".
When trying to bleed the rear wheels with ignition "OFF", no brake fluid comes out of the
brake lines; with ignition "ON" the fluid does come out of these same brake lines.
While driving, the car reacts rather well to the brakes being applied, but there seems to be
some hesitation when the brake pedal is pushed down firmly, which of course is not a
pleasant feeling.
Also when depressing the brake pedal (ignition ON), the red brake warning light comes on briefly.

Do you know what could be wrong?
Your help will be appreciated!
Tks.

H. Niekoop – Eindhoven – The Netherlands (Holland)  -  August 18, 2008

(Pls note that my e-mail address is .nl not .com)
E-mail address: hniekoop@scarlet.nl


ANSWER: Hi Henk:

Well first Off It's been a long time since I worked on one of these systems. It was a strange system to work on. My guess is there is some kind of and internal leak in the system and that is why you have the delay in braking and the red warning light comes on. That light somes on due to a difference in pressure from front to rear braking. Is the master cylinder you put in this car brand new or is it a rebuild unit or a used unit. My gut feeling is that the cylinder it's self is bad and it's causing your issue. when the key is turned on the pump builds up pressure and overcomes what ever internal leak there is and when the key is off the pump can't run thus the difference in the pedal feel and being able to bleed out the brakes. Hope that helps you out some.

---------- FOLLOW-UP ----------

QUESTION: To: donotreply@allexperts.com Attention Todd
From: hniekoop@scarlet.nl

Re: Delco Moraine Powermaster ABS III brake master cilinder
Model year 1989 -  2,8 l engine - 85000 miles.

Hi Todd,
Thanks again for your answer to my follow-up question.
I have one last question and I hope you have the patience to help me again.
Is it possible to replace the ABS cylinder on this car by a used none-ABS cylinder
from a similar car? I think these used non-ABS cylinders are easier to get.
If yes, what difficulties can I expect in doing this work?

H. Niekoop – Eindhoven – The Netherlands (Holland)  -  August 24, 2008
hniekoop@scarlet.nl


Answer
It can be done but by the time you convert it back to an non abs system you will more thna likely be at the same pice with parts as getting a new abs system. to convert it back you will have to replace the brake power booster and master cylinder. The lines for the brake are in a different configuration for that master cylinder so you will have to replace the lies at the front of the car. Also a non abs ystem car has propertioning vlaves in the rear lines I belive that is all incorporated in that abs cylinder so those will need to be added in ot the rear brake lines. So as you can see this is a huge undertaking and I do not recomend trying it. Either find the correct parts you need to fix this car correctly or sell the car and get something that is less of a headache. Like I steted before this system on this car was one of a kind a and mightmare from the get go to repair when they were new let alone almost 20 years old and the parts are VERY scarce due to the limited production of the system when the car was brand new.