TEVES brake pump/motor and pressure sensor swap.

[Machiner 55]

For some time now I've been having issues with the red and amber brake warning lamps on my 88. At first I was having trouble with the E-Brake switch but fixed that. I drove around a bit feeling quite smug that the issue had been resolved. A brief glance to the dash put an end to the reverie. Since I have two Reattae, I decided to swap out the accumulators. The problem didn't move with the swap. Good thing too, 'cause I didn't want to spend a hundred bucks for that little black ball. Back to the Bible (FSM) for more study.

I also started getting an occasional message on the CRT regarding low pressure in the brake system.

I used the diagnostics in the manual but got stopped when some of the tests required a break-out box and or a pressure gauge with fittings to measure hydraulic pressures in excess of 2500 psi. Neither of which do I have. I decided to swap the pump/motor/pressure sensor assembly. Only after pulling the one from the 88 do I come to find that the pressure lines off the pumps are different. The 88 has a flexible high pressure hose and the 89 has stainless tubing and the hole where they mount on the pump are, of course different. OK then. I decide to just swap the pressure sensor. Since I dont have a wrench that fits the sensor while it's in the car, I pull the pump/motor assembly out of the 89 also. After taking the sensor out of the 88 and comparing it with the one from the 89, I see that the 88 one is really "groady" I take the time to clean them both really well with Berrymans B-12 spray and using compressed air give them both, as well as the pump assemblies, a good blasting. (the pumps had the accumulators removed prior to this.) I then installed the pumps back into the cars they came out of with only the pressure sensors swapped. I checked out and fired up the 88 first.

Success!!! The brake warning lights light up when they're supposed to and, more importantly, go out when they're supposed to. Yeah!

Now on to the 89, the car I wasn't experiencing any problems with. I fully expected the problems I had with the 88 to be transferred to the 89. But they had not!!!!!!!! The brake system and warning light function as though there had been no change!

Wada youse guys and gals tink about dat?

Sorry folks, but my break's over. Got to go.

[Machiner 55]

Finished saga. (bump)

[Barney Eaton]

The problem may have been the sludge in and around the pressure switch. By cleaning it the problem may have gone away.

Whenever I work on a Teves system, I now pull the pressure switch and clean the switch and cavity. If you ever look closely at the cavity into which the switch mounts, you will note there is just a small orface between the switch cavity and the pump area.

Two things (or more) could happen. (1) the orface could become restricted by foreign material and/or old fluid. (2) because this cavity is isolated by the small orface from the rest of the system. The original factory brake fluid is trapped in that cavity. This can have a high moisture content and be contaminated by other materials plus it is very old.

The problem is removing the pressure switch. The hex is 36mm and it needs to be a thin wall. I had a 36mm impact (deep) socket machined on the outside to clear the pump motor and this greatly simplifies the removal. If anyone finds a thin-wall deep socket in 36mm size please post it here.

[Machiner 55]

Whenever I work on a Teves system, I now pull the pressure switch and clean the switch and cavity. If you ever look closely at the cavity into which the switch mounts, you will note there is just a small orface between the switch cavity and the pump area.

[color:\\"blue\\"] Yes, I noticed this.

Two things (or more) could happen. (1) the orface could become restricted by foreign material and/or old fluid. (2) because this cavity is isolated by the small orface from the rest of the system. The original factory brake fluid is trapped in that cavity. This can have a high moisture content and be contaminated by other materials plus it is very old.

[color:\\"blue\\"] Yes, this makes perfect sense.

The problem is removing the pressure switch. The hex is 36mm and it needs to be a thin wall. I had a 36mm impact (deep) socket machined on the outside to clear the pump motor and this greatly simplifies the removal. If anyone finds a thin-wall deep socket in 36mm size please post it here.

[color:\\"blue\\"] That's an excellent idea. If I can't find one ready made I'll try this. It sure beats using a pipe wrench. (leaves ugly little gouges.)

[color:\\"blue\\"] I have to tell you, I'm just eXtatic. (Go ahead, just aXe me!) Of all the possible causes for the problem and it was such a simple and inexpensive fix (cost me nothing but time.) My son has been dogging me about driving it for a couple of months now and I wouldn't let him because of the warning lamp issue. He's as elated as I am about it.

Thanks for your response Barney.

[Machiner 55]

They're baaaaK. The amber and red brake lights have returned after a brief respite. (About three days) But, their return has come in the 89 not the 88 where the problem originated. So it's conclusive now that I must change out the pressure sensor (switch). So, how much do they usually cost and who has them?

[Howard]

The GM part # is 25533700. www.gmpartsdirect.com shows they have this part at $84.10 + shipping. I bought one from that firm about 4 years ago and I think I paid about that for it. As I recalled, it took about a week and a half to receive. I would think there would be other sources that have this item too. Good luck.

[Machiner 55]

Hello Howard,

Thanks for the rapid reply. I found your earlier post using the search function on this site and used the info to search GM Parts Direct. Their drop downs don't list the part. I also tried searching for the part via the part number. It could not be found. In addition, I searched Auto Parts Giant, Advance Auto, Auto Zone and Jegs but no joy. I'm going to swing by Auto Zone on my way home from work (yah, I gotta work Sundays.) Sometimes they can order parts that don't show up in their online catalog. Will let you know what happens.

[Machiner 55]

Sometimes I'm such a dumb a**. I couldn't get the part number search function to work because I didn't delete the script [color:\\"purple\\"] (Enter Part #) that was already in the search box. Once I deleted it and pasted the PN you supplied it worked just fine. Also, I had help from a Chicago Viking who showed me that it could be done and damit, if somebody else can do it, I'll die trying to do it myself.

Thanks to both.

P.S. Auto Zone could not help.

[manikmekanik]

WHOA!!!

You actually got the search function to find what you were looking for???!!???

What are you, a programmer or something!!!

Now this is newsworthy! Whenever I've tried the search function here, all I get is everything ever posted with the word "it" in the title/description!!!

Not that it's what I'm asking for, but the word "it" is the only thing the list of posts returned have in common! Makes it extremely difficult to find needed info. Maybe if I search for something "not" what I'm looking for.

[Jim]

If you don't find a new one I have good used ones at reasonable prices. I have several Reatta parts cars and can be reached at jfinn@cpinternet.com

[Songman]

The brake system on the Reatta that I just bought is stamped 'Ate' in several places. Is this the same as the Teves system? Does this mean that the parts have been changed? I can't find anything that says Teves on the whole car.

[Guest MauiWowee]

ATE makes brake parts. If your Reatta is an '88, '89' or '90, it has the Teves system.

[padgett]

Albert TEves. Is now part of Continental.