I've tinkered with my fair share of brake problems or so I thought until this little gem of a problem dropped into my lap this week. While backing up my convertible into the garage - it stopped as normal hitting the 4x4 I use as a wheel chock - or so I thought - that was until I got out only to see I was still a foot away. Thinking I was against something I checked all tires and nothing! Hmnnnnn sure FELT like I "hit" my wheel chock - so anyways I jump back in pull forward and proceed to try again - same exact result. So I repeat going slightly faster and it then seemed "normal". Next time out the car drove and backed up fine - the driveway it sorta long - maybe 100ft anyways backed up no issues. Next day I pull it out of the garage and when I go to back it back in it does it again - this time I am convinced I am hitting/'running over something -check again NOTHING. I'm in a hurry and am quickly loosing patience - so I pull forward 3 or 4 times each time the wheels "lock up" about a foot short of where I need to stop - I pulled forward different amounts each time - Last time I am PISSED and floor it - nothing - won't budge - I use a floor jack to get it into the garage. That was yesterday. This morning - it did the same thing - so the problem appears to be there (or is at least worse when the brakes are COLD). Last winter I had the trans in a million pieces so bad thoughts are running thru my mind ;-( SO anyways I pull the wheels off and slip the drums off and low & behold the pass side rear drum is wet. Now this is far from the first time that has ever happened to me but it is the first time that it ever locked up the wheel while backing slowly. When I take it all apart I find a couple problems: 1. the rear wheel cylinder piston frozen 2. the self adjuster "button" (for lack of the right word) also frozen - almost missed that as the threads were fine - still showing anti seize from the last time I worked on it, but the thing couldn't rotate as the end was locked solid on the adjuster wheel. 3. Leaking wheel cylinder Fix those issues - hone it - slap it back together - dried the shoes with a torch (temporary - as I can't get those shoes quickly) and took it for a test back up - everything now OK. So I've never even heard of a leaking wheel cylinder causing this kind of problem, but surely appears to have caused it. The funniest part is how SOLIDLY it locked it up. At one point I FLOORED it and NO MOVEMENT at all -acted like a trans brake which made me fear it was something in the "fresh" trans, but put it in Drive and it goes forward no problem. I think the frozen wheel cyl. piston had something to do with the "directional" part of this problem, but still I've had that before and nothing ever acted like this. Anyways - I thought it a bit odd (and funny now- cause I was so pissed yesterday) so I thought I'd share- maybe see if it's happened to others and I've simply been lucky thus far.
Shoe drag set too tight, exacerbated by swollen brake linings due to fluid contamination, causing self-energizing brakes to grab and energize.
Yup it can happen! also make sure all the springs were there and in tact and the safety cable if its supposed to have one. I had a spring break and it would pinch between the shoe and drum every once in a while and stop the car short at low speed.
Gimpy - I thouht the same thing and expected to have to FIGHT to get the drums off - not so - they slid right off - I assembled it the same way - so far it's fine. I expected that the warm drum was bigger and it masked the problem when I would cruise it for a while and heat it up - but it didn't make sense to me that it slid right apart - cold. I was expecting it to be "locked" up cold and loose warm. Granted it may have been looser hot, but it came apart no problems at all cold. The "drag" was wierd - it'd move easy for a very short time & then lock up - I figured it was the shoes moving enough to "wedge". All this happened cold - and may have been happening hot - just not as bad. Slick Willy - yeah I had that happen once - I was 16 and inadvertantly knocked off that retaining washer & on the test drive - it jiggled around enough to wedge in between the shoe and drum making a heluva noise!!! This time all the pieces parts were fine.
brake fluid on a lining will cause the wheel to lock up, usely first noticed when driving on wet pavement.
The Jalopy Journal
