Rig Rolls back with Parking Brake On

[The_Handier_Man1]

From: Jena8601  (Original Message)
Sent: 10/8/2004 5:39 PM

I was wondering if anyone has had this problem.. or if it is a problem with the 76 Winnie.   
We had the back breaks done, and noticed when we got it back that the parking brake doesn't seem to hold to well.  It will roll backwards if in neutral with the brake on.  But it does not roll frontwards.  Just wondering if something is wrong with the parking brake.  Thanks in advance for any help



From: denison
Sent: 10/8/2004 8:08 PM

I presume yours has the parking brake located inside the rear brake drums, instead of being on the end of the transmission?
Your symptoms are a sign that the parking brake is out of adjustment.
The way it operates: it will have slightly more effectiveness when the hand brake is engaged and the rig rolls forward, than it will when the rig rolls back. This also applies to many cars that have drums brakes in the back.
The adjustment is three-fold.
First and foremost are the self adjusters inside the rear drums. As you back up repeatedly in normal operations, they will -or they certainly should- adjust the brakes shoes to be right up close to the drums. Then it wont take much -travel- of the handbrake cable to move the shoes out far enough to hold the drums from turning. The guys who worked on the brakes could have done this adjustment; but if your self adjusters are working, normal operation will take care it just the same.
The second part of the adjustment is done where the rear cable connects to the front cable. There would be a long threaded rod and a nut to adjust for length. Usually all rusty too.
Thirdly there should be adjustment possible from the handbrake handle beside the driver. When the brakes are released you should be able to rotate that handle. It its threaded rod can lengthen or shorten the handbrake cable -action- an inch or so. Its common for that thread to be siezed up from age and inaction though.
Worse yet, its common for the handbrake cables to be stiff with age and lack of use. Then when you release the handbrake after use, it doesnt fully relax, but instead holds the brake shoes bearing somewhat against the drum. This increases brake shoe wear. If your handbrake cables look rusty on the outside, they probably are on the inside too. It might be worthwhile to replace them - even though it can be a fairly long and dirty job.