Uneven braking in The rear (original drum brakes) 2.5-3 on The left and 0.8 on The right. All looks good, brake shoes looks good. Wheel cylinder looks good, no leaks. The drum has A trace in it but is overall good. What should i do? Where to Begin? Hard to find parts to Pontiac 54s in sweden. Any other GM part fitting on my brakes?
Wheel cylinder piston bind due to moisture absorbed in the brake fluid over time, rust in the cylinder bore.
Have the brake shoes ever been oil or brake fluid soaked? If so, the contamination will never be able to be removed.
Kinked or internally rusted line. Back to wheel cylinders--rust inside the bore limiting piston movement, even though movement has been observed. Have to think about how many possibilities that the restriction is coming from, look at everything.
my old Hollanders interchange manual says Pontiac brakes only, 49-54 are mostly the same. So you won't find much else to get parts from, unfortunately. If all the parts you can see look identical on both sides, then it is probably something you can't see. As suggested, the wheel cylinders or lines could be corroded or plugged or something. Wheel cylinders are available for a reasonable price from places like rockauto.com, I don't know if they ship international.
Should check The brakefluidline for air. Take down The wheelcylinder and dissect it? Was Hoping i wasnt going to need to buy new gear since i would not have it in time... But new wheel cylinder and shoes May just Solve The problem, just don't in time.
Just as i feared.. Well will check that store for parts, like i said. Ponchos 54 and earlier is Hard to find parts over here.
If you are watching the shoes move without the drum on there is still a possibility of air or moisture in the system. That may not show up until there is actual pressure in the lines with the shoes contacting the drum. Are the drums within spec ? The rears are the furthes from the master so maybe a good thourough flush and bleed will help out.
Each wheel on axle must be singing from the same page. So any and all repairs and maintenance must be performed in axle pairs. Drums should be same diameter. Rubber brake hoses are notorious for this, sticking wheel cylinders, weak return springs, worn backing plate shoe pads.. Then, even with serviceable components installed they need to be adjusted correctly. Start from that point where everything is adjusted as tight as can be adjusted, and back away from there. Adjustment attempts from the other direction will leave too much "slop" or clearance in the brakes.
Are the rubber lines old or new? If old, replace them and see if it evens out the braking. The hoses can collaps inside, preventing pressure from getting through. Inverse, if you get on the brakes really hard it can force fluid through and then trap it on the cylinder side causing the brake on that side to drag until the pressure bleeds back throught the hose restriction. I found this out the hard way on a daily driver.
Bleed out The bad side then i skrew/turned them soo They both took likewise on both sides, they Where very uneven at first. Made them equal then turned The good side looser and The bad side tighter. From 3 left 0.8 right to 1.7 left 2.0 right, it passed. ( max diff in sweden 0.3)
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