brake dragging 5ktq PROGRESS

[Grant Lenahan]

Well, you've found your culprit - but not exactly what it is doing 
wrong.

As the abs controller sits, what if valves are stuck in odd positions? 
Or get moved slightly by hydraulic pressure and they apply pressure 
(but being off, it cant release it)?

I'd leave it connected. A non-functioning part that is still inthe 
hydraulic path is a problem waiting to occur.

Grant
On Nov 22, 2006, at 11:36 AM, Doyt W. Echelberger wrote:

> Thanks for all the replies. As suggested, I put the car on a lift and
> checked all the testable mechanical factors ...and they all were OK:
> Emergency brake cables/caliper levers, caliper pins, caliper piston
> function, flexible line condition, master cylinder function (new), all 
> new
> brake lines, new brake fluid, good Pentosin level, reasonably working
> accumulator (10 pumps).
>
> Only two factors seemed questionable:
>            (1) The car sits idle and only gets driven every few weeks, 
> and
> then not very far or very aggressively.
>            (2) The ABS electricals were disconnected under the rear 
> seat a
> few years ago, to prevent chatter at rolling stops (corroded cogs in 
> the hubs.)
>
> What action did I take?  I re-connected the ABS pigtail at the 
> controller
> box under the rear seat. Then I drove the car aggressively for 15 
> minutes,
> making 8 stand-on-pedal tire-skidding stops from 50 miles and hour, 
> maybe
> 30 seconds apart.....a variety of the infamous Italian tune up.
>
> What were the results?  After the third skidding stop, the brakes 
> stopped
> dragging and the stops got cleaner and easier and the car rolled 
> easier on
> acceleration and deceleration. I couldn't make the ABS chatter like it 
> did
> when the car was new and I can't explain that. Seems that if the tires 
> were
> skidding/wheels were locked up, the ABS should engage and rattle like a
> machine gun. Anyhow, the brakes stopped dragging and when I parked the 
> car
> out of gear on a level surface I could push it both ways by leaning 
> against
> the hood or the trunk.
>
> Future Action?  I'm gonna put some Blaster on the nut that holds the 
> ground
> wire at the front of the ABS unit under the hood. I'll clean up that 
> ground
> connection and test the ABS again, with wheel-locking stops, and see 
> if it
> can be made to chatter in its original alarming fashion. Never thought 
> I'd
> want to have it work that way again. Oh for the good old days!
>
> Thanks again for all the replies.....anybody with an idea is still
> welcome.....this isn't over with yet.
>
> Doyt
>
>
>
>
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