Re: [DML] Re: "Bench Bleeding"

["Ed B." <mr.pants@xxxxxxxxxxxx>]

> Harold McElraft wrote:
>
>Are you sure the rear brakes are working ok? That is, the pistons 
>are not stuck, lines are not blocked, etc. Have you tried a vacuum 
>bleed at the rear calipers until the fluid is clear?
>

Yep... the rear callipers are new (not refurbed... new) & working 
properly.  The lines are good: no blockage, no swelling, etc.  I also 
swapped back to the old callipers with the same results.  (In fact, 
there's nothing wrong with the old callipers & the old pads were next to 
new as well, but I had a new set of complete brakes/pads that was part 
of a bulk purchase I made, so that's why I put them on when I had the 
wheels off to do some other work on the suspension).

I definitely properly bled the callipers the old-fashioned way); clean, 
fresh fluid throughout, no air bubbles, several bleedings.  I changed: 
master cylinder, callipers, pads & rotors, so it could be any of these, 
although I know the callipers are good & all the rotors & pads were new, 
purchased from DMCH.  I did not bleed the master cylinder because I 
thought it would bleed with the system, as in my other cars, so I will 
try this when I get her out again in the spring-time (it's in storage 
now).  If it does not fix the weak rear braking problem, at least it 
will be properly bled and I can eliminate this as a possibility.

I drove the car for about 800km (500 miles) after the brakes were 
swapped, so everything should have "broken in".  Rob at PJ grady 
suggested checking the pads & rotors so, for kicks, I put in the old 
pads and the braking was BETTER.  The "new" pads were all smoothed out 
by the rotors.  Could the rotors possibly be to blame for the poor 
grip?  I sanded the surface before putting them on; I assume they are 
"ready-to-wear", so to speak, no??  They look totally new still; no 
marks.  Again, in spring-time when I bleed the m.c., I'll swap back the 
old rotors and see if this is the culprit.

Right now, I know I should try re-bleeding the m.c. properly, then the 
callipers & that way I'll know I'm starting off with a correctly bled 
system.

Thanks for everyone's suggestions so far... with a new suspension & 
steering bits and a lot of hard work, I need to drive my baby and not 
worry about stopping issues!

- ed

1982 DMC-12 [11594]
1986.5 928S
1990 Coupe Quattro 20V



>
>  
>
>>I,too, have less than stellar braking since I replaced my master 
>>cylinder, rotors, pads & callipers.  So bad, in fact, that with 
>>    
>>
>the car 
>  
>
>>up on jack stands and the engine & tranny in 1st gear idling (no 
>>accelerator applied), all my weight on the brake pedal will just 
>>    
>>
>barely 
>  
>
>>stop the rear rotors from turning.  
>>




To address comments privately to the moderating team, please address:
moderators@xxxxxxxxxxx

For more info on the list, tech articles, cars for sale see www.dmcnews.com

To search the archives or view files, log in at http://groups.yahoo.com/group/dmcnews 
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/dmcnews/

<*> To unsubscribe from this group, send an email to:
    dmcnews-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/