bleeding new rear calipers? (pre-93 type)

[Andy T 0]

Just fitted new rear calipers, they both came plugged with a grub screw so assume they were already filled with fluid, I bled them after fitting and i've got a spongy pedal. the nearside one didn't seem to want to bleed aswell as the other side, it passed some fluid/air through but then stopped doing anything (using a pressure bleeding kit) the offside caliper continously was passing clean fluid through with no air.

 

Any clues? should I off bled them 'off' the car? if so, which position should the bled screw be in, top or bottom?

 

The level in the master cylinder did drop to the 'min' mark at one point ( the fluid pickup tube fell off inside the bleeding kit container) could that of caused any problems?

 

 

cheers.

[RW1 0]

it passed some fluid/air through but then stopped doing anything

 

Possibly the internal rubber tube has collapsed inside the rubber brake hose on the back trailing axle arm if you have originals fitted. If it was already restricted and now blocked except under extreme foot brake pedal pressure, all the air may not have been cleared. No real way to check externally but they usually show signs of sweating fluid (like condensation) when they have split internally or the ball shaped bulges in the outer rubber protection. If so, replace both axles as the other will follow soon.

 

Nothing special in bleeding the brakes. You appear to have done it OK. And a pressure bleeder technique should clear & fill the caliper normally.

 

Min mark is of no consequence. Lower would affect the clutch possibly.

[Andy T 0]

cheers for that.

 

the clutch is fine so reservoir must be ok. I will bleed the master cyl just to be sure.

 

the funny thing is, I had to replace the rubber hose on the near side trailing arm because the Goodridge hose had been cross threaded into the old caliper (some previous twit) so now I have a standard new GSF hose on that side.

 

the caliper does appear to work on that side, the pads gripped the disc when pumping the pedal after bleeding.

[Henny 0]

did you have the car jacked up when you tried to bleed the brakes? The load compensator would have been letting almost no fluid through to the rear brakes if it was which makes bleeding the brakes bloody awkward to say the least. Sounds to me like there's still some air in the rear brake pipes...

[Andy T 0]

yeah I had the compensator tie wrapped so that it would be fully open.

 

would bleeding by the two man method be more effective at pushing fluid through?

[Henny 0]

Cool, it's one that a lot of people forget about... 8)

 

The two man way shouldn't be any more effective, but it may be worth a go as that's the only way I do it due to not having a one man kit... :lol:

[carpy25 0]

bleed screw should be at the top because air rises

 

 

the hand brake cable enters the calipers either on top or on the bottom it

the newer type has the hand brake on the bottom i think but the bleed must be on the top whichever ones you have

 

easy to put them on upside down (on the wrong side ) heard about it loads

 

 

ROB

[Andy T 0]

Sorted now!

 

Yep, bleeding again using the brake pedal sorted it, and I didn't even have the bias valve pressed in.

 

Quite a lot of dark mucky fluid came out, which was all pretty clean looking when bleeding the other caliper first time round?