Kit ing dual master cylinders?

[GPster]

I was so excited that the '87 S15 that I rescued out of the junkyard for the the frame (and engine?) had enough power to climb the short ramps and on-to the trailer that I didn't realize that if there hadn't been a stop at the front of the trailer it would have gone into the tailgate of the pull-truck. On investigation I found the master cylinder to be low on fluid and when I added some I left the cover off of it to see if one chamber went low real quick so I would know which end to look for a leak on. Pushing the pedal down gives me a gyser in the back cylinder of the master cylinder so a guess that the piston seal is bad. My guessing is just taken from experience with Kit ing old style single master cylinders. Can dual master cylinders be Kit ed? Is it financially reccommended? Most repair shops seem to be getting re-built master cylinders but I want to start out cheap at least till I get this stripped out to a rolling chassis. I have no idea if this thing has a long list of interchangables to start looking for one off another junker. It would be a guess if it was any good or not. I havent asked any dumb questions here for days. GPster

[enjenjo]

Yes you can buy a kit, but check pricing. On many of them you can get a reman cylinder at about the same price as a kit.

[wayne petty]

I was so excited that the '87 S15 that I rescued out of the junkyard for the the frame (and engine?) had enough power to climb the short ramps and on-to the trailer that I didn't realize that if there hadn't been a stop at the front of the trailer it would have gone into the tailgate of the pull-truck. On investigation I found the master cylinder to be low on fluid and when I added some I left the cover off of it to see if one chamber went low real quick so I would know which end to look for a leak on. Pushing the pedal down gives me a gyser in the back cylinder of the master cylinder so a guess that the piston seal is bad. My guessing is just taken from experience with Kit ing old style single master cylinders. Can dual master cylinders be Kit ed? Is it financially reccommended? Most repair shops seem to be getting re-built master cylinders but I want to start out cheap at least till I get this stripped out to a rolling chassis. I have no idea if this thing has a long list of interchangables to start looking for one off another junker. It would be a guess if it was any good or not. I havent asked any dumb questions here for days. GPster

i have found out from experiance that reman masters do work but not for long.(1 year)..many brands of new masters also have the same problem...   too rough a finish in the bore. the rough finish wears out the lip seals.  oem masters previously have a bearingized finish... they used roller bearings in an expandable mandrel to bring the bore to a finished size... there was an artical on using that same type of technology to resize cam bores for V8 engines.

[BFS57]

Hello;
Well, as some of you know, recently I had to re do the master and booster on my 32. I got really good parts and prices from a small co, named Pirate Jack! All, I can say is check them out.
It is cheaper than re building the other part.
I got mine off an auction on EBAY. Both the 7" booster and dual master cylinder were under $100.00 with shipping!

Bruce

[GPster]

Well today's reality is maybe the only thing wrong is me. The junkyard that sold me the S15 gave me another master cylinder. One of the yard mechanics pointed me at the best donor because everything else on the brakes was new and he new the truck was junked because the engine quit. I took out the master cylinder with the lines to the block so that the fluid wouldn't leak and air wouldn't bleed in and I came home. Changed it out and had the same gyser (old faithfull?) that I did with the first. Two bad in a row? I was without a computor to cry here so I went to talk to the neighbor who was working in his repair shop. I explained the gyser and he said they do that. He was bench blleding a new master cylinder the other day and had not put the cover on it and got fluid all over his vise. We talked some more an he figured the reason the pedal went so low is because I didn't have the motor running, power brakes. and because the front of the first master cylinder was empty when I first checked it that block had probably sealed off the rear brake circuit and it would need to be reset. So I proceeded to do a job I thought was in my expertise. I started breaking out the broken windshield. I went to the Social Security Office to get a paper showing that I am totally disabled so I can apply for a Homestead Exemption cut on my property tax. If they could follow my progress on this project they'd have no problem with my classification.. GPster