Rear drum brake issue ( LONG POST )


Amateur Racer
Aug 15, 2010
Ontario , Canada
Need the help from you guys. The issue is with my street driven car, which has front disc and rear drum brakes. Everything worked perfect when taken off the road. Car was in storage for 4 years and now I am trying to get her back on the road. Bled and cleaned front calipers, working OK.

Rear brakes are not getting any fluid: pulled bleeder nipples and pumped pedal, zero fluid.
Went to proportioning block and front line port leaks fluid when opened, rear line port is dry.
All parts were new & installed in 2000.

What are the simple steps to find where the issue is. Proportioning block 1st, then check the booster which is a disc/drum 9in unit.

Wish I could just go to the store and purchase a new prop. block but nobody around here ( Rural) stocks this stuff so I need to diagnose what my problem is first. thanks Larry


Amateur Racer
Aug 15, 2010
Ontario , Canada
Forgot to ask, will a proportioning valve work on my application for the street. Dont know if this would be as good as a stock prop . block,,,,,,,,,


Dragway Regular
Nov 6, 2009
Dayton, OH
I had the same problem recently myself.My car sat for years so I decided to replace the front brake lines and the proportioning valve but not the rear lines.So after I installed these parts I began trying to bleed the brakes and I could not get any fluid to the rear at all.After trying that several times I removed the proportiong valve and found the safety switch inside the proportionig valve had engaged.So I manually reset it and still no luck,somehow it engaged again.This happened to me three times and I never figured out why.It's not easy to remove the proportioning valve so I was a little fed up.I was able to exchange my new proportioning valve for another new one and I also bought a new master cylinder and all new lines to the rear and just replaced everything.I then took it to a local shop that hooked up a small compressor and pulled the fluid to the rear and they bled the brakes for me.In the end it was a little pricey(approx.$400 )but worth it to me.Its probably not your booster.I was told the way to reset the safety switch and get fluid to the rear is to open the front bleeders and have somebody get in the car and hit the brakes hard.While their feet is to the floor close the bleeders.Repeat 3-4 times then check to see if you have fluid to the rear.Not sure if that will work/help but thats the advice somebody gave me but by then I already bought new stuff.The only other way I know of to reset the safety switch is to take it off the car and manually reset it.New brake lines and proportioning valve are available at MikesMontes,sponsor on this site.Sorry about the long response but I hope this helps a little,good luck.

LS6 Tommy

MalibuRacing Junkie
May 15, 2004
North Jersey
Last edited by a moderator:


Amateur Racer
Aug 15, 2010
Ontario , Canada
thanks for the ideas guys. Will mess with the combination block in the morning, and as a back up I have called car quest to see if we can get a replacement asap. Let you know how this saga ends up . Larry
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