77 brake question

[Ralph140]

You all a re a welth of knowledge. I ahve searched the techs but still ahve a couple of questions.
I have a 72 with a 77 disc brake system out of a FJJ55. I was given a M/C and booster as well. My 72 booster is shot but my 72 M/C is in good enough shape to rebuild.
The 77 M/C is toast due to too much rust. Will the 77 Booster work with my 72 M/C ?
Also there is a valve of sorts (marked front and rear) under the 77 M/C and attached to the booster. Is it a porportioning valve and do I need it? that valve is in pretty rusty shape too. I cant find any references to this valve, or kits. Do they still sell this vavle? And am I better off with the 77 or 72?

 

[dgangle]

It may. Bolt it up and see. This is easy enough to find out quickly. IIRC the 77 is a dual diaphram so it is going to be longer. The brake lines may be able to be bent to reach their new locations or you may have to alter/replace/make new/learn to double flare.

That is a non-adjustable proportioning valve. If your front to rear brake bias is right then leave it alone. If not your options are to live with it, replace with like or replace with an adjustable one like

Summit SUM-G3905 - Summit Brake Proportioning Valves - summitracing.com