THE PORTAL HUB - Pinzgauers, Haflingers, Volvo 303s and more!

I'm new to the forum, I signed up a couple months back because a guy across the street from my shop has 2 710's and a 712 that he runs a scenic tour business from. I've done some maintainence on them, full fluid change, boot swaps, etc. mainly with the help of you guys on this site. Thanks a bunch!!

I've run into a problem that I can't figure out on the 6 wheeler tho... He acquired it this spring and it had a pulling left issue when braking. I adjusted the shoes the way I have always done (inspected them as well and all were looking good) and it made the situation better, but never totally took it away. Now the problem is back with a vengeance... On a gravel road, at about 20mph I can stand on the brakes and lock up all 3 wheels on driver side, but passenger side only pushes a small amount of gravel with center axle. I cannot get the front passenger to lock up no matter what I do..

I have so far;

Bled that side of the vehicle 17 or so times, doing it the way I always have, the way the book says, the way some guy did when I was a kid... I even built a pressure bleeder to reverse bleed, pulling excess out of the master for 4 full cycles on each of the right wheels. No change..

I changed the pads and rotor on front right to a new set the owner had ordered. Seemingly when they were ordered the owner was told that they were all built as matched sets and not to mix up pads with rotors because they wouldn't work correctly. Never heard this before, but I followed what he said. No change..

Replaced the wheel cylinders on front right, then power bled again. No change..

Readjusted the pads to the book numerous times to no avail. I can't keep this thing from wanting jerk itself right off the road under hard breaking. Pulling my hair out here..

If anyone has some other suggestions please let me know. It's turning into busy season here for his tour business and I need to get this working safely as soon as possible...


Thanks
Brad

Please list your location.
I do hope you have the repair manual, if not you need them, they provide good detail on proper brake adjustment.
I suspect that you are not adjusting the brakes correctly, the following threads may help.
viewtopic.php?f=15&t=6879&hilit=adjust+brakes
viewtopic.php?f=15&t=7038&hilit=adjust+brakes
viewtopic.php?f=15&t=6879&hilit=adjust+brakes
viewtopic.php?f=15&t=5833&hilit=adjust+brakes
viewtopic.php?f=4&t=4077&hilit=adjust+brakes&start=30

I am working on the assumption that the 712 has a stock brake system with drum brakes for all six wheels. Your use of the phrase

I changed the pads and rotor on front right to a new set the owner had ordered

is confusing as a stock 712 has drums and shoes, while some have had aftermarket disk brake conversions.

Yea I apologize for the mis-speak It is original drums all the way around. I have 2 books here related to the Pinz, the first being I believe the shop manual for 710 and 712, half german I believe, and half English, with poor pics of anything important. The second is a labeled "repair manual" and includes sections on body, drivetrain, electrical, etc. I've followed the procedure outlined in the first book to the letter.. 3 times in the case of the right front wheel.. I have to suspect that there is something I'm not doing properly as well, simply due to the fact that everything on that wheel is brand new, and the lines I know for certain have no air in them.

I'll have a dig through the links you provided and see if anything I did is far off.

Location is Ridgway, CO. USA.


Thanks
Brad

edit;

I just noticed you were in Coeur d'Alene... We just finished a Diamond T for a customer up there.. Maybe you'll see it at some local shows.

IIRC, the right front wheel is the one where the adjusters are backwards threaded from all others on the truck. (It's been a while...) Is it possible you're adjusting things in the wrong direction?

I've read about that issue, but adjusting the until the drum won't turn, regardless of the direction, is what I've been doing. I start with the upper/rear wheel cylinder, tighten until I can't hand-turn the drum, then back off 3 clicks. Then repeat this procedure for the lower/front wheel cylinder.

I'm not new to drum brakes.. This is the most frustrating part of this adventure. It's a pretty simple system. Parts good? check. Fluid good and air-free? check. Brakes should work... UNcheck...

Front left (and I should say, whole left side) works as advertised. Right side however, mainly front axle, is another story. If I had hair I'd be pulling it all out.. I've got 3 full days into this brake "issue" with nothing I've done showing any positive results..



Thanks
Brad