New master cylinder on the way

[Niori]

I'm getting ready to replace the master cylinder in my truck. Can anyone recommend a good way or tool to use to help make t easier for me to bench bleed it before installing it?

Having to replace it, because apparently it has been replaced before I got it, and I'm thinking that someone just went to a salvage yard and got a master cylinder, because the one on it is for a C/K20 Diesel with 11" rear brakes... Mine is a C20 gas with 13" rear brakes. I could just get the master cylinder gasket that firs it, but who's to say that 1, 2, 10 years down the road I'll have to replace the gasket again, and I won't remember the issue I had trying to find the proper gasket this time

 

[SquareRoot]

what gasket are you referring to?

 

[Niori]

what gasket are you referring to?

The cap gasket

 

[Niori]

Came across a new issue tonight when trying to bleed the brakes. I found that I have a line, facing towards the passenger side front the proportioning valve, has a leak in it, and it's shooting fluid out.

Is there a way to fix it (even if just temporarily) so I can get it to a shop and have the line replaced? Or can anyone tell me how far back the line goes, so I might be able to pull it myself and take it somewhere to have a new line made?

 

[78C10BigTen]

Came across a new issue tonight when trying to bleed the brakes. I found that I have a line, facing towards the passenger side front the proportioning valve, has a leak in it, and it's shooting fluid out.

Is there a way to fix it (even if just temporarily) so I can get it to a shop and have the line replaced? Or can anyone tell me how far back the line goes, so I might be able to pull it myself and take it somewhere to have a new line made?

I think some pics of said line will help here.

 

[Raider L]

@Niori,

If fluid is coming from the passenger side of the proportioning valve, you should have already lost the brakes on the front. The valve hasn't shuttled? You know that if there's a leak at any point the valve will shuttle and shut off the brakes either in the front or rear so you don't loose brakes altogether? You need to see what is causing the leak. The nut just have come loose there. You could undo it and carefully put the line back in and snug it down making sure it's not cross threaded. If there's a crack in the line, let the valve shuttle and you should still have rear brakes to get to a place you want to take it to get it fixed.

Of course, the object to owning a Square body is learning how to fix it yourself. Get the tool kit to make brake lines with and learn how to do it. You can get those tool kits at most any auto parts store. They're not very expensive. Also, you can get you a small tubing bender so you can learn how to put bends in you tubing to.

The best tool you can get first, since you asked about tools is called a "Mighty Vac". It's a hand held vacuum pump that has a set of plastic/rubber fittings for different zerk fittings and clear hoses of different sizes. The pump will allow you to suck down your brakes by yourself with no more having someone inside "pumping" the brakes. You can do all four corners in a half hour or so. I have one and they are great. Also, the kit has all kinds of other automotive functions even drawing a vacuum on a carb power valve to see what it breaks open at, 6.5 Hz or whatever. You won't use it for that very often but it's nice to have it if you need it.

As far as a gasket for the MC res., you can get those in the "Help" section at most auto parts stores. Don't bother to get one from Summit, you can get one anywhere.

 

[Raider L]

Well, I was just thinking, is there a difference between a C10 and a C20 Master Cylinder? I don't think so, unless it's one of those hydroboost things.

 

[75gmck25]

There was definitely some type of HD brake option (RPO J55 and JB5 vs. JB6 vs. JB7 brakes) in certain years, and it’s been discussed in other posts here. I think it affected calipers and rotors, but I don’t know about other parts.

Bruce