Excellent Info regarding Delco Brake System

[Paul93Lotus]

http://www.tpsgarage.com/

Then click on brakes link.

[Jonathan]

Good find, very useful, well shared

[Paul93Lotus]

The more I read about this system, the more I want to see if it is possible to convert to the later w-body style abs that had a vacuum booster. This sytem is just plain doo-doo. Pressure switches and accumulators seem to go out more than replacing spark plugs. And it is starting to look like buying parts new as far as the master cyl is starting to be a problem. The systems are so expensive, that for people that own the cars that had these systems, the cars are usually junked because the system costs almost half the value of the car!! I went to two self serve yards and found one car that had one, but the pressure switch was melted (?!), the accumulator had rust on the bottom, and the master cylinder had brake fluid that looked like used motor oil.....but I was still considering buying it as a spare just for the master. I think I am going to do some measuring to see if the vaccum booster would fit....it's pretty tight under the bonnet of a lotus.

[fmxa]

May be I'm reading this wrong, but are you really looking for a master cylinder in a junk yard? FWIW they only cost ~$100 new from JAE in Santa Barbara (I just changed mine a few weeks back). I also recently saw a vacuum boost conversion on a 93 done by Harry Appleby in Costa Mesa.

The more I read about this system, the more I want to see if it is possible to convert to the later w-body style abs that had a vacuum booster. This sytem is just plain doo-doo. Pressure switches and accumulators seem to go out more than replacing spark plugs. And it is starting to look like buying parts new as far as the master cyl is starting to be a problem. The systems are so expensive, that for people that own the cars that had these systems, the cars are usually junked because the system costs almost half the value of the car!!  I went to two self serve yards and found one car that had one, but the pressure switch was melted (?!), the accumulator had rust on the bottom, and the master cylinder had brake fluid that looked like used motor oil.....but I was still considering buying it as a spare just for the master. I think I am going to do some measuring to see if the vaccum booster would fit....it's pretty tight under the bonnet of a lotus.

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[Paul93Lotus]

I was there for another car I own, but knew which models had our braking system in it, and saw a 1990 turbo grand prix in the yard. I was thinking as a possible spare. Since this braking system is nearing obsolete status (it has not been used in a GM car since 1991...) It won't be long where the only alternative will be a rebuild or used.

I had an anti lock light come on (blinking) last week, and think that more than likely it is either the accumulator or pressure switch. I depressurized the system by pumping the brake pedal 40 times. Turned the key to on...heard the pump run for about a minute, and have not seen the anti-lock light since. But I imagine that it will be back at some point.

[Paul93Lotus]

May be I'm reading this wrong, but are you really looking for a master cylinder in a junk yard?

Edited May 10, 2006 by Paul93Lotus

[fmxa]

Well there isn't much attached hardware on a master other than the rod and cap! Mine was simply remove the rod attached to the old master cylinder (as I didn't want to re-adjust the clutch pedal) and move this to the new unit and install! I have a spare pressure switch out of my S4s if you want to try that (also had the flashing ABS but turns out it was the accumlator)?

As for the conversion, I'm not certain - give Harry a call 714-979-1020

Good luck and hang in there!

P

Well...the complete assembly (master,pump,accumulator,pressure switch,solenoids) runs over $1000 at almost all GM dealers. Are you talking just about the master all by itself? Delco-Morraine not Kelsey-Hayes? Without zero attached hardware?

Was the vacuum boost conversion a GM system? Did it have anti lock?

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[Paul93Lotus]

How much did you get your accumulator for.....and where if I may ask? B) I am leaning toward the accumulator as the pressure switch has a black plug so I guess it had been replaced at some point? Plus I have yet to see the regular red brake light come on, which is a usual indicator of a bad pressure switch?

Well there isn't much attached hardware on a master other than the rod and cap!  Mine was simply remove the rod attached to the old master cylinder (as I didn't want to re-adjust the clutch pedal) and move this to the new unit and install!  I have a spare pressure switch out of my S4s if you want to try that (also had the flashing ABS but turns out it was the accumlator)? 

As for the  conversion, I'm not certain - give Harry a call 714-979-1020

Good luck and hang in there!

P

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[fmxa]

First thing I'd to do is hook the car up to a TEC1 and confirm it is indeed a pressure issue and not a bad sensor etc, any GM dealer should be able to do this for you, may cost you $50, but worth it before you tear into things. If you're near Costa Mesa drop in on Viking, if you ask nice they'll probably hook it up and check the codes for free.

As for price ~$100 sticks in my mind, and I believe it's GM part #25528382 - check out the parts cross reference guide in this forum, it should all be there, then hit your local GM dealer, www.gmpartsdirect.com or call JAE in Santa Barbara. BTW - The newer pressure switch is grey, with the old one being black, so it sounds like you have an old one.

As for the red brake light coming on, I've never seen this behavior with the two pressure switches I've been through, it's always been a flashing ABS light. FWIW I'd replace the switch and the accumulator, as Murphys Lotus Law says you change one component the other will fail within a month.

You also may want to look at disabling the delco ABS; you've probably already figured out it's a load of crap and more of danger than an aid - search the web, there's a site with detailed instructions on how to do this.

Good luck, and if you do replace either component be certain to put lots of rags around the area as brake fluid tends to get everywhere no matter how much you depressurize!

How much did you get your accumulator for.....and where if I may ask?  B)  I am leaning toward the accumulator as the pressure switch has a black plug so I guess it had been replaced at some point? Plus I have yet to see the regular red brake light come on, which is a usual indicator of a bad pressure switch?

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[CarlC]

You also may want to look at disabling the delco ABS; you've probably already figured out it's a load of crap and more of danger than an aid - search the web, there's a site with detailed instructions on how to do this...

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FWIW. I have had my ABS disabled since the back end of last year. Its just two fuses to remove. It gives a slight improvement in pedal feel and I prefer to know where the cars brake limit is. Also means I have to be a little more sensible with my driving, which is no bad thing.

This is just my preferance. But as its so easy to disable it can be worth trying it to see what you think.

[fflyingdog]

How much did you get your accumulator for.....and where if I may ask?

Edited May 15, 2006 by fflyingdog

[fflyingdog]

Ooops !

Edited May 15, 2006 by fflyingdog