|
Author
|
Message
|
|---|
Anon
Deleted
Posts :
Location :
Status : Offline
|
Trouble bleeding my brakes
Ok the van failed the MOT. I changed the rear shocks and had a hand doing some welding, but the brakes weren't balanced properly.
I remembered that one of the brake cylinders was a bit stiff last time I was messing about with them so thought I would just go ahead and get a couple. But while I was changing one of them, the one there wasn't even anything wrong with, I broke a brakepipe. I had to wait for all this jubilee crap to pass before I could even get a new one made. I fitted it this morning and you would think the next thing would be to bleed the system.
But the campers not having any of it, me and a kiddie managed 2 1/2 hours of bleeding or attempts at bleeding as there is just no pressure in the system.
would there be any reason why fluid comes out of all the bleed nipples except for the passenger front side when pedal is pressed.
with the lack of pressure and no fluid coming from one of the brakes it's like I could still have a brake leak, but there are no leaks.
should I just keep bleeding until whatever pressure there is forces fluid through the other brake
----------------------
|
 Wed 06 Jun 2012 @ 23:03
|    |
Anon
Deleted
Posts :
Location :
Status : Offline
|
Sounds like a large enough air pocket in a line to prevent fluid passing when bleeding normally so try this.
Park van on ground (not tarmac) that can be hosed down.
Find a stick of wood that fits between the seat or seat base and the brake pedal when fully depressed.
Open offside front bleed nipple, pump brake pedal using quick strokes until fluid jets from the bleed nipple, insert stick of wood when pedal depressed then close bleed nipple.
Top up reservoir, remove stick then repeat for nearside front bleed nipple, then rear nipple/s (1 nipple on 9-inch brakes, 2 on 10-inch brakes & CF2 - bleed offside first when 2 bleed nipples).
Once there's a good jet of fluid from all bleed nipples, bleed as normal in the same order to scavenge out the last air bubbles.
Last: hose down van & ground to remove brake fluid.
If nearside front still won't bleed and the pedal has good resistance otherwise then suspect a blockage, e.g. forrin body in the line between front tee piece and wheel cylinders, brake hose deteriorated internally.
----------------------
|
Thu 07 Jun 2012 @ 00:58
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
thanks for the reply, but I already thought of something like that. I couldn't see how there would be more pressure in the system while pumping the pedal as opposed to when the pedal is held down. plus you've got the extra worry of pulling more air into the system.
it looks like I'm just gonna be stuck bleeding the brakes all afternoon, I'm sure there's nothing wrong with the brakes apart from air and no pressure on pedal.
any more ideas would be appreciated, thanks
----------------------
|
Thu 07 Jun 2012 @ 09:58
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
If there's no pressure felt at the pedal then the master cylinder itself may need bleeding first.
This can be done by detaching brake union/s from the master cylinder & then closing port/s with a finger on upward travel of brake pedal until fluid jets from port/s. This ensures that fluid is drawn from the reservoir instead of back in through the port/s when pedal released.
Once fluid jets from port/s, refit union/s then move on to bleed nipples at wheels. Don't forget to wash down bodywork where brake fluid has landed.
Normal bleeding then may work fine if the problem was just the master cylinder gulping in air but if it doesn't work then do the rapid pumping thing.
Rapid pumping of the pedal with a bleed nipple open works by beating draw-back of air pockets in the system that can defeat normal bleeding procedure.
There's no pressure increase to speak of unless there's a blockage in a line being bled this way.
----------------------
|
Thu 07 Jun 2012 @ 10:48
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
If there's no pressure felt at the pedal then the master cylinder itself may need bleeding first.
This can be done by detaching brake union/s from the master cylinder & then closing port/s with a finger on upward travel of brake pedal until fluid jets from port/s. This ensures that fluid is drawn from the reservoir instead of back in through the port/s when pedal released.
Once fluid jets from port/s, refit union/s then move on to bleed nipples at wheels. Don't forget to wash down bodywork where brake fluid has landed.
Normal bleeding then may work fine if the problem was just the master cylinder gulping in air but if normal bleeding still won't work then do the rapid pumping thing.
Rapid pumping of the pedal with a bleed nipple open works by beating draw-back of air pockets in the system that can defeat normal bleeding procedure.
There's no pressure increase to speak of unless there's a blockage in a line being bled this way.
----------------------
|
Thu 07 Jun 2012 @ 10:56
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
It was the master cylinder, I bled it a little and there is now fluid at all bleed nipples.
There is a couple of problems though, one is that the brake that is farthest from the cylinder, rear nearside never has much pressure in it and the other is the fact that all the brakes still have low pressure.
should bleeding solve this?
I think I should have one last bleed tomorrow morning then it's off to get it's MOT retest.
----------------------
|
Thu 07 Jun 2012 @ 17:29
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
With the master cylinder working you could find that bleeding the system is all that's needed now.
----------------------
|
Thu 07 Jun 2012 @ 18:36
| |
Anon
Deleted
Posts :
Location :
Status : Offline
|
cheers you've been a great help.
i think you have been on more than one occasion, so extra thanks the thing will be on the road again tomorrow, hopefully
----------------------
|
Thu 07 Jun 2012 @ 19:37
| |
|
Time in GMT
|
New posts since your last visit
Old post