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Paul in SC
08-06-2012, 10:56 AM
Would someone please supply an exploded view from the manual of the MC with the proportioning valve for a 93? I do not have a manual and would like to verify the correct install of the valve.

I installed a DRM bias spring and the instructions show what appears to be an older model MC with the valve being backwards if compared to the actual on the one I removed. Since install, my brake warning light has remained on...another issue.

Thanks :handshak:,
Paul

ghlkal
08-06-2012, 09:25 PM
Paul, would the diagram of a 1990 MC help? If so, I can email it to you (for some reason my photobucket account is locked out right now) - pm me your address.

ghlkal
08-06-2012, 10:20 PM
[Cliff is a genious ... someone give him a raise ;)]
http://www.zr1.net/forum/picture.php?albumid=184&pictureid=1296

Paul in SC
08-07-2012, 08:22 AM
Thanks for the reply. That is similar to the view of the valve that is in the instructions with the DRM bias spring. When I pulled the valve out from the MC on mine, it was in the reverse position with the bias spring and c-clip coming out first and nearest the plug. According to this, the end with the bias spring goes in first closer to the booster.

Did the MC change for later model Zs or should I repull the valve and replace as illustrated? I don't know if the warning switch will line up in the the groove in the valve in this position. That is my question.

My warning light is on and will not go off since the work. It was not a problem prior. The brakes work fine. I have not gone through a panic stop yet, just normal bedding and driving.

Other comments or suggestions are welcome.

Thanks again for the illustration,
Paul

Paul in SC
08-07-2012, 08:29 AM
In addition, as I look at this illustration, I see the secondary piston (7) that would push against the valve. With the valve in the current position with the bias spring at the plug side, what is the piston pushing against and what action compresses the bias spring on the other end?

I believe the valve was put in backwards prior to my removal and reinstall. To what purpose I do not know and why wasn't the warning switch activated if this is the wrong position.:confused::confused::confused:

HELP!?

Paul in SC
08-07-2012, 01:21 PM
Call off the hounds. :stop:

I found a diagram of the MC for 92-94 and the install is correct as on the original. The reverse was for the 90-91, dual resevoir unit. So I know it is intalled correctly.

Now to trouble shoot the warning light.

Thanks,
Paul

FU
08-07-2012, 01:47 PM
Is the bias spring the same thickness as the one that was in the car ?
There is an air bubble in the master cylinder causing the brake warning light to come on. Bleed the MC.

Paul in SC
08-07-2012, 02:17 PM
Hey, Frank.
How ya doing?

I put a DRM spring in it which is heavier than the one that was there. We also put GS calipers on the front and new rotors and Hawk pads. Bled at each caliper and seem to be working fine. We did not bleed at the MC so I guess that is our next step.

Thanks for the reply.

Paul

batchman
08-07-2012, 05:05 PM
I put a DRM spring in it which is heavier than the one that was there.

So Paul, if you don't mind my asking, I saw what I understood to be a DRM bias spring (with no instructions) and it looked a lot more like item 7 than item 18 - which was it?

Thanks,
- Jeff

Paul in SC
08-08-2012, 08:14 AM
So Paul, if you don't mind my asking, I saw what I understood to be a DRM bias spring (with no instructions) and it looked a lot more like item 7 than item 18 - which was it?

Thanks,
- Jeff

Jeff,

I did receive a diagram with the spring from DRM, however, it showed an earlier year MC not a 93 or newer since it had two individual resevoirs rather than 1 main unit as in mine. This one showed the proportioning valve in the reverse position inside the MC versus the installed position in mine. That was the question in my original post.

The number "7" referred to the piston in the booster that pushes on the proportioning valve. This was shown in the diagram that ghlkal sent in his email. In the same diagram, the number 18 that you mention is a smaller spring that is located at the plug end and not the bias spring. In the diagram there is no reference to the bias spring because it is inside the valve.

I have answered my original question about the correct install of the valve since I found a diagram that shows the correct MC for my year. I am okay with that now, I just have to get the warning light to go out. Hopefully, get to it this weekend.

I hope this answers your question(s).

Paul