Brake trouble

Well, I have pressure at each brake, though the front bleeders just dribble, I'm wondering if that's a pressure issue or if the bleeders are clogged/rusted up. I only assumed it's the proper proportioning valve, but it doesn't have any extended nipple to depress anywhere, and doesn't look exactly like this.. brake proportioning valve for power brakes - International Scout parts. Think I might just end up putting a generic valve in and adjusting from there. The thing does stop pretty well if I give it two quick pumps, but if it's just the first brake application it pretty much sinks almost to the stops and then feels like old style manual brakes (secondary system?). Thanks michael.
 
If the front calipers simply "dribble" fluid, then you have issues with them being plugged internally. Remove the entire bleeder nipple and see if the posts then allow full fluid flow. If a nipple is partially/fully clogged, simply install a new one from the parts house.

These parts are nothing complicated at all, simply a tapered sealing tip that matches the receptacle in the caliper body. However, any old caliper or wheel cylinder will certainly fail/corrode internally over time, that is why we replace 'em when they don't work as spec'd.

Your parts description tells me this system is botched from years ago. Most likely started off as a drum/drum system and and was partially converted but does not have the correct proportioning valve. A disc/drum system must have a properly operational proportioning valve or have an aftermarket single circuit valve installed in the rear system and then adjusted for proper four wheel braking action.

Having to double-pump the brakes also tells me there is probably no residual pressure valve set installed in the master. A drum system requires an rpv of approximately 10psi, the disc side requires an rpv of approximately 2psi.

Anytime the brake vacuum booster is changed out,the connecting rod that mates the booster piston to the master cylinder input must also be adjusted in order to have a proper relationship.
 
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