Ok, got a Question..issue with my 72 ((HELP needed))

[SEVEND2]

Ok, just been driving it past couple of days, replaced front calipers and brakes becuase front clipers locked up. any how

say i am getting off the freeway/highway when i drive for a little while the front starts to shake bounce around and i exit the ramp and it bounces more when i aply the brakes, it bounces a little when i take off, and then smoothes out. when i come up to the next light i let off the gas and slow (with out hitting brakes) and the front bounces alot. and it that way till like it sits for a while a few hous and then its fine again till i drive it for a while again.
ANY IDEAS WHY OR WHAT COULD BE THE PROBLEM? SHOCKS, BRAKES??

HELP!!!

[firedog]

i had that problem once with a car and ended up replacing the brake lines to the caliper. It was explained to me that the rubber goes bad inside the hose also and it forms a little flap that only alows pressure to go one way then wont release it so it caused the caliper to stay shut but in time the pressure works it way back past the bad spot in the line and lets the caliper release. Just a try and i am no mechanic but an experince in the past.

[Longhorn Man]

Have you looked at your tie rod ends?

[Boones]

have you checked the balance on your tires... or the front suspension bushings

[SEVEND2]

_found so far my propotioning valve is leaking my brakes are set up for 1 line T off to feed both front brakes, so i plugged the other port (un-used) well its bleeding fluid past the plug. I just drove it today about 2 miles and i smelt brakes bad (pewwwwwwwww) any how i am just about tired of the issue and might take it to my local shop... unless anyone else has ideas, :-)

[old Rusty C10]

did ya over tighten the front wheel bearings?

[SEVEND2]

hmm nope dont think i did,

[SEVEND2]

Sorry to rack your brains for me on this one, i know its hard to see the issue with out driving it or seeing it for your selves, but i really hold everyone in high regards for the help!!!

[skyhawk1]

Sounds like the rotors are warped to me.

[Blazer1970]

The hoses are bad as mentioned above. I know it is hard to believe, but they swell shut inside, and do not let the calipers release.

[SEVEND2]

ok, well this is my day off, so i guess ill tear in to it today and see what turns up... thanks. ill post any thing i find or dont find

[Mark Mazzanti]

When your front brakes are locked up, Jack the front of the truck up. If both front brakes are locked up you probably have a master cyl. or proportioning valve problem. If it is only 1 wheel locked up it is a brake hose or caliper problem. If both wheels are locked up try loosening the line on the proportioning to the front brakes and see if that unlocks the brakes, If not try loosening the line on the master cyl. and see if that unlocks the brakes. Also check free play in your brake pedal, you should have at about a 1/2 inch or 1 inch when the brakes are not locked up.

[dubie]

I had the exact same thing happen on my 82 a few years ago and it turned out to be front end troubles. I ended up replacing tie rod ends and all the ball joints. The front end was so worn that when you applied the brakes to quick, or you were turning a long curve. I would say your front end needs some work. Excellent diagnosis Andy

[SEVEND2]

OK got New calipers both sides, new proportioning valve I hardly have any travel in the brake pedal now. It seems the pressure is good enough to squeeze bast a plug i have in the top of the proportioning valve. where the optional front brake line would go. It seems after it sits for a period of time it rolls just fine. then back to tightening up. like the calipers dont release fully. But i will give it a little more of my time!!!!! Thanks . any thing else you can come up with Please post for me!!! Thanks again!!!

[Mark Mazzanti]

You should have free play in the brake pedal. You can pull the master cyl. away from the brake booster and shorten the brake pedal rod a little by screwing it the rod down on threads. Iam not sure what you mean about an extra port on your proportioning valve. Do you have the brake warning light wire connected.

[mdill]

My 72 had a bad master cyl, that would hold presure in the front lines when released. Have
heard of lines causing the same sorts symtoms
but never seen it my self.

[Long Knight]

Probably not applicable, but don't make fun of me. I just had this problem on the hydrolic clutch on my bike, would not release the pressure. Turned out the pressure release port (or whatever it is called) that allowed the excess fluid to return was plugged. It was so small I had to use a bristle off a wire brush to clean it out and it bairly fit. Anyway, do these MCs have a release port (or whatever you call it) so the lines don't hold pressure?

[SEVEND2]

ok, slaved and worked on it, Father inlaw helped out and we figured it out!
get this!!!

The Master cylinder and brake boster was the problem, The shaft on the booster was to far back in to the cylinder not letting the shaft travel back enough to open the return port(hole) for the fluid to depressurize the brakes.
So I used a washer between the the master cylinder and booster then put them together and all is well i gots Brakes that release now.

Just and FYI for anyone that might come across this in the future!!!

Thanks for everyones help and comments, i did try a few of them first!!!

[Long Knight]

Does this mean I win something? J/k!

[SEVEND2]

Probably not applicable, but don't make fun of me.


You win MY THANKS!!!!


your comment made us check that.

:-) i am a happy camper now!!!!!!!!!!!!!!

Time to

[Long Knight]

Did you take some pics of the stuff disassymbled?

[SEVEND2]

Nope i didn't, i dont have a digital yet, so i would have had to wait anyhow. :-(
I am happy i can drive and brake without smelling the brakes so much cause they would not release