bleading brakes

[Faceplant]

Hi Again,

After one of my rear brake pipes failed a couple of weeks ago i've been on a merry-go-round. I replaced the pipe and bled the caliper, brakes are light under foot and not working. I read the manual which suggested bleeding the brakes in order of furthest from the master cylinder. When i got to the front kerb side caliper the bleed nipple was so rusty and jammed the top of the nipple broke off!

Cars fitted with marina master cylinder and ford escort mk3 brakes

Found a replacement caliper at euro car parts. Fitted. Done....

Nope, bled all brakes in order with engine running morris marina master cylinder, and brakes are not working.

bled again without engine running, not working.



checked the replacement pipe at the rear, all ok, checked front caliper i replaced, looks ok. not sure where to go now, covered in brake fluid and i just want to drive my minor again!!

using dot4 fluid, and bleed valve.

[kittyfell]

There are many methods including just letting gravity take it's course. In desperate cases it's best to get a helper to pump up the brakes, you then snap the nipple open and closed, they then release the pedal and then re-pump the pressure etc etc. Never known to fail.

[charlie_morris_minor]

one other trick when bleeding brakes is when you release the brake ready for the next pump, move your foot side wise so the pedal goes back with a bang as opposed to just lifting your foot off, the idea is that a sudden jolt might / can release a trapped air bubble.

[bmcecosse]

If you only replaced a rear pipe, and the master cylinder wasn't allowed to run empty, then you should only have to bleed out the rear brakes.

[Faceplant]

would the level of the car make a difference? my drive has a small slope

[bmcecosse]

Master cylinder needs to be the highest point.

[Faceplant]

I didnt think bleeding brakes would be this hard!

I had another go last night, going round to each wheel and bleeding, pumping brake, i did it about 2-3 times on each wheel in turn and it felt like i was getting somewhere as he brake pedal was getting stiffer. However when i run the engine i loose any stiffness in the brake and i have nothing still.

I'll try again tonight, but was wondering if i am supposed to have the engine running when bleeding?

[kittyfell]

I think it was said earlier that if there is servo, then the engine must be running to operate the servo. Also some split circuit brakes need front and back to be bled at the same time to allow the master cylinder to run full stroke. Do you have split circuit brakes?

[Faceplant]

The brakes are from a morris marina, the fluid filler has 2 places that draw the fluid, one for front and one for rear. So i guess thats a split circuit?

how can i bleed them at the same time?

[Alec]

Hello Kittyfell,

I have never bled brakes with the engine running, the servo only provides assistance. Also I have never bled both circuits simultaneously on a split circuit car, but then I've only ever owned one. It had two servos however!
Bleeding shouldn't be this probelamatic, so it makes me wonder if there is a poor connection somewhere, but that should be evident as fluid would be lost there?

Alec

[Faceplant]

thats what i thought, i left the car overnight and no leaks, i pump the brake with engine off and i can feel the build up of pressure, no leaks there either.

i rechecked the 2 parts on the system i replaced, they seem ok, no leaks! might build a brick wall instead.

[morrisfixer]

Hi,
I had the same problem on my Morris, Fiesta discs and Fiesta
master servo. You blead the brakes over & over and still nothin,
turned out to be a leak in the master cylinder! Answer replaced
it with a new one Have you tried pressurising the system!
It might help you
steven

[MarkyB]

When you bleed the brakes is there still air coming out?
If not there might be an air lock somewhere.
If you are, the master cylinder is probably the culprit.

[bmcecosse]

Lots of Mini lads have bleeding problems - until they bleed front and back at the same time, and with servo operating. Just need two tubes and two jam jars!

[Faceplant]

had another go last night with engine running and had a little bite on the brake pedal, not enough to stop properly though. will try with a 2nd bleed kit and my dads help tomorrow!

[morrisfixer]

You shouldn't have to run the engine to bleed the brakes, I've
never herd of that one. Sounds it's likely to be air in the pipe
that runs to the back. You should try clamping the pipe over the
back axle, then bleed the front brakes. Try pedal. Then clamp off the front
brakes and one of your back brakes then bleed the wheel without
clamp then swap over then after all that take each clamp off trying
the pedal as you go
p.s If that doesn't work find the biggest hammer........ Lol

steven

[Faceplant]

something else to add to the list! cheers steve.

[bmcecosse]

I NEVER EVER clamp pipes - shortly after - don't be surprised to see clamped pipes swelling and perhaps bursting! Wasn't that what started this whole episode.........

[Faceplant]

didnt need to clamp, my dad gets the credit for this one, previously using the bleed kit didnt do me any favours. while dad pumped the brake pedal and held down while i released releasing the bleed nipple. Went round the car a couple of time and its all good again.

Luckly i had cleaned and polished in anticipation of a sunny day and country roads.

Thanks for everyones help,

Till the next time

[Matt]

I assume you are getting fluid coming through and out of each of the nipples?