Hi - I've got a DL240 '86 station wagon and am about to replace the master break cylinder. I have a serious break fluid leak and while I don't know for certain it's the master break cylinder - I am assuming that's what the problem is as there are no visible wet areas ion the bottom of the inside of the wheels - as there would be if the leak were at a wheel's break cylinder.
The leak is from the engine area.
I think I know what I am doing - as I did this years ago on another vehicle. But one thing in the manual troubles me; it says I may have to bleed the transmission hydraulic locking mechanism. This may or may not be as simple as bleeding the individual wheel cylinders. Also, in my manual there are diagrams - not specific to a 240 - that show multiple bleeding points on each wheel! Is this true? Are there more than the break cylinder of each wheel to be bled?
So - I'm looking for some advice here in case there's anything I'm missing.
Thanks!!! Dagaan

 

arrrgh, pet peeve, its BRAKE not BREAK. BREAK is what happens when BRAKES don't work

there are various different brake calibers used on these cars, some are dual piston, others are single piston. some have dual bleeders, others have single bleeders. look at see what you have when you take the wheels off.

I have no idea why you'd need to mess with the transmission, or what the 'transmission hydraulic locking mechanism' is.

what manual are you looking at ? most of the aftermarket manuals (Hayes, Chilton) are basically awful. Bentley is a little better.

 

Thanks for reply Pierce -

I'm sorprized that misspelling got past me as I am narmolly a gud speller!

Hmmm . . . dual bleeding points on the wheels; OK. I think my book is a Hayes and that biz about the 'hydraulic lock' or something like that was mentioned - maybe not for my model but I was airing the possibility in case it was. I assumed it was what caused the tranny to lock up when in park.

It looks like it's not the master cylinder at all (phew - less bleeding) but the O ring on the electric sensor of the break fluid 'proportioner'. Either it got a. swollen from the fluid over time b. was the wrong size to beigin with or c. simply was not tightened down sufficiently. This sensor a plastic nut with a typical, square, copper electrical connect sticking up. I'm going to look into whether this is replaceable and comes with the correct O ring. But tightening it may have been all that's been needed - for about seven years! (It turns out the car used to belong to my lady neighbor who gave the car up for another when a mechanic told her that 'the break lines were full of holes' - right. Could someone have been pouring in a quart of brake fluid every two months for seven years? Sure!
I am begining to see why people love Volvos. This car has had very little maintainance but runs great! I just discovered the brake pads are non existent and the cylinders were hot as a frying pan when I took the tire off immediately after driving.
So - what I'm looking at now is a possible leak in the left front brake cylinder - and if the one needs replacing probably best to do both. So - if you have any tips on these issues they will be gratefully received. Thunks! Dagaan