Page 1 of 1

Brake bleed order?

Posted: Wed Jan 13, 2021 11:28 am
by Chill59
What is the correct order for bleeding the brakes on a minor? (it's a pick up if there's a difference).
I know you start with the furthest away from the master cylinder and work back.
I was wondering whether the pipe to the 'nearside front' was longer (further away from the master cylinder) than the 'offside rear' pipe.
See the attatched to see what I mean.
Cheers Chris

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 2:30 pm
by Murrayminor
Start at the rear, the rear wheel cylinders are a bit of a strange design and allow pockets of air to sit in the cylinders.

I have bled my minor as follows and it worked for me:

Bleed the brakes as you would normally, starting at the rear finishing at the front, Then I sat the car overnight with the brake pedal depressed and allowed the air to work its way to the bleed nipples.

I then modified an ezibleed kit using a non vented Minor master cylinder cap, tapping the top and attaching the tube.

I then fitted the ezibleed, gave it some pressure from a tyre (about 20psi if memory serves me correctly) and repeated the above.

Had a nice feeling pedal.

hope you get sorted, I'm sure there will be an easier way and someone will be along soon to point that out but the above is my method.

Above all make sure the air is out of the system.

Good Luck.

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 2:54 pm
by Sleeper
Not nit-picking , but,

" Then I sat the car overnight with the brake pedal depressed and allowed the air to work its way to the bleed nipples. "
How would it do that?

Unless your're on a hillside?

John ;-)

Air in the brake pipes/lines will move to a certain extent with the flow of fluid ,press the pedal slowly and they could remain where they are , a vigorous pumping action will force them along , other than that they will flow to the highest point of their own accord , due to their density ( similar to lack gravity in reverse ).

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 2:57 pm
by philthehill
In addition to the above jack the car at the rear as high as you can before bleeding.
This helps as it encourages the air to rise to the highest point in the system.

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 5:51 pm
by Trickydicky
With respect to the learned, why would you want to jack the car to some strange angle to bleed the brakes and leave it overnight with the brake pedal depressed? They wouldn’t do this if you took the car to a garage :o
If the brakes have had a full overhaul the best place to start is at the front drivers side, use the 2 man (or woman) method with a tube and jam jar depressing the brake pedal while opening the bleed nipple, when the pedal is at the floor close the nipple, repeat until airless fluid appears at the nipple. Then go to the other side and do the same and then onto the rears.

If you have only replaced one cylinder then bleed that one first and go around the others starting at the rear offside to check for air using the method above.

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 6:58 pm
by Chill59
Trickydicky wrote: Wed Jan 13, 2021 5:51 pm If the brakes have had a full overhaul the best place to start is at the front drivers side, use the 2 man (or woman) method with a tube and jam jar depressing the brake pedal while opening the bleed nipple, when the pedal is at the floor close the nipple, repeat until airless fluid appears at the nipple. Then go to the other side and do the same and then onto the rears.
I thought you started furthest away from the master cylinder and worked towards it?

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 7:01 pm
by Murrayminor
Yes indeed I forgot to mention raising the rear of the vehicle.
It forces the air to the rear where it can be bled slowly.
Leaving the brake pedal depressed keeps some pressure in the system.

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 7:29 pm
by philthehill
Some Minors are really terrible to bleed the air out of the hydraulic system and require the rear to be raised to great heights.
Been there, done that.
Make sure brake fluid does not leak out of the master cylinder cap vent when the rear is raised/
Phil

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 7:59 pm
by Trickydicky
Chill59 wrote: Wed Jan 13, 2021 6:58 pm [quote=Trickydicky post_id=662962 time=<a href="tel:1610560272">1610560272</a> user_id=15158]
If the brakes have had a full overhaul the best place to start is at the front drivers side, use the 2 man (or woman) method with a tube and jam jar depressing the brake pedal while opening the bleed nipple, when the pedal is at the floor close the nipple, repeat until airless fluid appears at the nipple. Then go to the other side and do the same and then onto the rears.
I thought you started furthest away from the master cylinder and worked towards it?
[/quote]

Normally you would but if the system has been fully replaced, to get fluid into the brake lines starting at the front offside is the shortest line. Once fluid is in the brake pipes and by following the above method every time you depress the brake pedal and close the bleed nipple you are pushing fluid through the brake pipes to each cylinder.

https://www.popularmechanics.com/cars/h ... ed-brakes/

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 8:12 pm
by Chill59
philthehill wrote: Wed Jan 13, 2021 7:29 pm Some Minors are really terrible to bleed the air out of the hydraulic system and require the rear to be raised to great heights.
Been there, done that.
Make sure brake fluid does not leak out of the master cylinder cap vent when the rear is raised/
Phil
What sort of height are we talking about Phil?

Re: Brake bleed order?

Posted: Wed Jan 13, 2021 10:23 pm
by philthehill
As high as you can get without being ridicules.

Re: Brake bleed order?

Posted: Thu Jan 14, 2021 9:30 am
by Sleeper
" Leaving the brake pedal depressed keeps some pressure in the system. " ,

How does this help?

John ;-)

Re: Brake bleed order?

Posted: Fri Jan 15, 2021 2:53 pm
by Murrayminor
Sleeper wrote: Thu Jan 14, 2021 9:30 am " Leaving the brake pedal depressed keeps some pressure in the system. " ,

How does this help?

John ;-)
With the rear raised the pressure forces the air to the highest point so it's easier to bleed usually left overnight.

Re: Brake bleed order?

Posted: Fri Jan 15, 2021 3:18 pm
by Sleeper
The brake lines may be under pressure , but will have no effect , any trapped air will slowly migrate to the highest point in the system of it's own accord .

John ;-)