I'm replacing the master cylinder in my 40 ford pickup with a mustang dual cylinder. Its is under the floor. I was wondering if anyone had pictures of how they connected the front and back brake lines. The connections are on the transmission side. I'm sure it can be done but want it done correctly and to look good. Thanks for any help.
The new master cylinder should be here today. will get it installed and take some pictures. Will probably have to get help posting them.
You didn't say what brake system parts you are using but there are a few rules to follow if your MC is under the floor. You need a 2# residual valve between the MC and a disk brake caliper, 10# residual if it is drum brake. If you have disks in the front and drum rears just plumb the valves into the lines going from the MC to before the line "Ts" off to the individual brakes. You may not need it but a manually adjustable proportioning valve is handy plumbed into the line going to the rear brakes. Some MCs have the residual valving built into the MC, if yours does either remove them or don't put in the external ones.
Extra residual pressure valves won't hurt if there is already one in the master. See here: http://www.ecihotrodbrakes.com/brake_facts.html They are also a good source for the RPV, as theirs is made of brass instead of the cheaper aluminum ones sold elsewhere.
Run a 90 right off the master, one pointing forward for front brakes, one pointing backward for rear brakes. The 90 doesent have to bottom out on the master, but get it pretty tight, use some red locktight. Dont use a brass 90, use a steel one. This will keep your lines closer to the frame and away from the trans, without the funky bends.
If you use any fitting directly on the master, make sure it has the proper end to seat in the master. Usually there's a conical seat in the master, so an inverted flare should seat against it. Just using tight threads (this isn't a pipe thread joint) is NOT good enough. If the casting on the master is machined flat directly around the outlet, it might be possible to use a banjo fitting with appropriate crush washers. But maybe not.
I understand your concern, but the steel 90 will do its job. The steel 90 will seat with the threads, its tight after the first couple turns and if you set it through all of its threads, it aint gona leak. It basically becomes an extension of the master. The fluid dont know the difference. The 90 is basically no different than a steel master cylinder adapter fitting, with a flair seat on the female end just like an adapter fitting.
I just get the proper size fittings and bent up new tubing to fit. Be sure you run the lines correctly ( front to front ect ) Randy
Greatings from Australia. Randy and the other posters, great information. I am putting discs on my 47 buick and have wanted a dual master cyclinder as well. Randy could you send me a couple of pictures of how the pedal input goes into the cyclinder. My email is trackless54@hotmail.com. thanks a lot. My pedals arethe old style pivoted at the bottom
If you have clearance issues with the fittings, I believe a Ford Torino has fittings on the opposite side of a Mustang
Thanks all for the great info. My concern was clearance. I will get the 90 degree elbows and that should solve the clearance issue. Right now I'm waiting for my engine. It's a flathead and the builder put in the wrong pistons. Hope to get it back soon. Thanks again
Three things. First, I don't remember seeing a steel 90 with a 45 degree male end. Mixing 37 and 45 degree fitings is plain wrong, if that's what you suggest. Second, The use of ANY sealant with straight threads on a brake system is not needed or wanted. The flairs and seats do the sealing, not the threads. Third, brass, not steel fittings, are what should be used with brass tubing seats found in brake system components.
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