Brakes Again

Thought I'd post a new one since I had the rear left brake caliper changed on my 94 Nissan Primera 2.0L.

Brakes still feeling a bit spongy with probably a bit too much travel. A few pumps at the lights and they're solid again, though I think it did this before.

Still rather concerned about the lack of bite.

So I looked under the bonnet, and found the brake fluid reservoir almost overflowing. funny, I thought, it weren't doing that t'other day after the caliper had been fitted.

Any explanations?

Bizarrely though, my taking some of the fluid out of the reservoir, actually seems to have made a little difference and brakes seem a bit firmer.

Is that possible?

I was hoping that caliper might just need beddnig in, but I think that Im barking up the wrong tree. I note they've also smeared copper grease on the right hand brake shims, which Im confused about, since they shouldn't have done anything to that one.

Before the repair too, I could drive down the road, apply the handbrake and it would grip the rear wheels and slow the car down. It has very little effect at the moment. But at least the handbrake is now working better than it was and actually holding the car on a hill when parked.

I'll be getting it booked into the garage (or maybe another one and send them the bill), but thought I might ask here before I start getting any waffle.

Incidentally, could the blued up brake disc on the left side explain any of these symptoms?

Cheers Simon

Reply to
Simon Dean
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It sounds like it needs bleeding again. Take it back. The pads on the rear will take a bit to bed in,

Reply to
Duncan Wood

The master cylinder needs bleeding and/or an overhaul.

(A) "Master Cylinders"

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(1) Under "Diagnostic Overview" (3/4 down the page) "A master cylinder also has two ports in each area of piston travel. The rear port, which is called a "breather" or replenishing port, fills the cylinder's bore with fresh brake fluid." "The forward port, called a compensator port, allows the master cylinder to force air from the cylinder's bore into the master cylinder reservoir. The compensator port also allows brake pressure to be released when the master cylinder piston is fully retraced in its bore..." "...if either or both of these ports are blocked by sludge or rust, it will prove difficult to bleed the master cylinder and its related hydraulic components."

This accounts for "the brake fluid reservoir almost overflowing".

(2) Under "Causes of Failure" (1/2 down the page) "Technicians may also contaminate master cylinders by forcing the caliper pistons back into their bores without isolating the caliper. High- mileage systems are particularly vulnerable because the calipers may contain rust and sludge that will cause the master cylinder to behave erratically or fail altogether."

This is the same sludge or rust referred to in (1).

(B) The hand brake holding efficacy is a separate issue.

Reply to
Lin Chung

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