mikevyota

I recently swapped a 86 rear axle into my 82 p/u. With issues of the tire's rubbing on the frame, this housing worked out great. The tubes are larger and the brakes are as well. But this is my problem. After bleeding the brakes three times and double checking everything, the pedal still doesn't feel the same as before. I know the wheel cylinders are larger, and therefore require more fluid, but the master cylinders are the same according to three parts houses in town. All rear brake parts are new except for the drums, new w/c, shoes, and hardware. The drums have a good bevel and no real grooves in them. Has anyone ran into this? Wouldn't adding a proportioning valve make my problem worse? I know people out there have done this swap, so please let me into the fold on this problem. Thanks.

mikevyota

5 days and nobody knows what I'm talking about? Come on!!!

Intrepid

I swapped in a wider rear axle on my '85. On the first pump I have hardly any braking, but on the second I have amazing braking. I haven't solved the problem yet, but I will let you know when I do.

I was told last week that it might be a rear adjustment issue (maybe the drums are way too big (been resurfaced too much), the rear shoes are worn way too much, or a combination of both. Could also be the LSPV acting up. My pads are new, but my drum is old, like you, my drums appear to have plenty of material on them, the pvalve is not connected to the axle, but it is the same as it was with the last axle so I assume it must not be the problem. I also have a new MC so that shouldn't be the problem either.

Did you find a solution to the short e-brake cables? If so, you can pull the e-brake and drive in reverse, that is supposed to adjust the rear brakes.
Have you checked to make sure they are adjusted all the way?
Have you bled them in the proper order?

mikevyota

I ditched the load valve a long time ago, so rule that out. And the e-brake cables, I can't say 'cause I run a driveline brake. I had the problem you were talking about( brakes suck until you pump them once, then good). That turned out to be the front wheel bearings were loose. When you first step on the pedal, the calipers were taking up slack aginst the rotor, then working fine. My problem was air in the new rear wheel cylinders. I talked to Marlin @ Marlin Crawler( great guy and shop BTW), and he said he's running the same setup as us( front SA discs, rear IFSaxle/10" drums), and he had the same problem initally. He said he gravity bled the brakes one at a time and found air in the system still. Marlin said he runs the stock, 1980 M/C with the 10" drums and the brakes feel like stock. He also said I was bleeding wrong in the past, going to fast when manually pressure bleeding. He recommended gravity bleeding, then slowly pushing the pedal down while watching for air. He also said to maually bleed, do the up/down thing then wait ten seconds until doing it again. He said you can force air from inside the booster into the lines(?). Maybe old dudes do know what they're talking about?

Intrepid

Thanks for the info, I planned to spend this saturday making my best effort to solve this problem.

millertime_t1

Take off your master cylinder --- pull out the actuating rod --- spin it a few times (make it longer) --- 10 minutes your problem will be solved --- I spent days and dollars trying to figure out this simple fix!

mikevyota

Marlin also told me this, take the slack out of the pushrod. Thanks.

millertime_t1

no problem