Normal brake bleeding problems :-(

Post by **paulhumphries** » Fri Nov 17, 2006 8:16 am

[/quote]
What is a Mityvac[/quote]

It's a hand operated vacuum pump.
http://www.mityvac.com/
Has numerous uses but the main one I find is for bleeding brakes.

Paul Humphries

Post by **RogerRust** » Fri Nov 17, 2006 8:36 am

I think the problem lies in the rear cylinder design and arragement.

I know this has been discussed several times but here are some pic to illustrate the problem

This is the path the fluid takes when bleeding the rear cylinder.

There is only a small hole in the cylinder;

My solution is to fill the cylinder with brake fluid just prior to bleeding like this;

I hope thats not teaching my grandma to suck eggs, but I thought it might be usefull

Post by **paulhumphries** » Fri Nov 17, 2006 5:51 pm

Hooray - managed to bleed them at last.
In the end just perservered with the two person method.
I don't think I've ever used so much fluid to bleed a cars brakes before !

Paul Humphries.

Post by **picky** » Mon Aug 20, 2007 8:51 pm

im having some trouble with bleeding the brakes, im going to leave it overnight with one of the rear wheels on an axle stand, im hoping air in the system will try and float to the top, and gather at this wheel.

Picky

Post by **bmcecosse** » Mon Aug 20, 2007 9:21 pm

I just open the nipple with tube attached in a bottle - and then drink a cup of coffee. It bleeds through all by itself. just keep topping up.
Have you modified the brakes in any way - fitted a servo ?

Post by **picky** » Mon Aug 20, 2007 9:32 pm

the brakes are standard on the rear, and wolseley 1500 on the front, no servo. Reason I am having trouble I think is because I have rebuilt the master cylinder at the same time as fitting the front brakes, so lots of air in the system I imagine.

Picky

Post by **rayofleamington** » Mon Aug 20, 2007 9:36 pm

I've never had a problem using a crow bar or stout screw driver. There may be something about the saloons that makes that impossible, I guess...

nope - it can be a total doddle on saloons too

The only tricky one I had was when I tried to lever against an 18" piece of wood on the floor pan right next to the chassis leg, but the floor pan was a bit wobbly

Regarding a soft pedal... I would slack off all the brake adjusters as much as possible - this allows the pistons to move and the fluid into and out of the cylinders may allow you to disturb (and hopefully remove) any trapped air.

Post by **dunketh** » Tue Aug 21, 2007 11:29 am

You can avoid any possibility of air being drawn back in past the bleed nipple threads if you do it the tedious (two person) way.

You mean theres another method?

Admittedly I cheat by using a tube with a one way valve in it (basically a ball bearing). They can blow but they can't suck!

Post by **rayofleamington** » Tue Aug 21, 2007 8:30 pm

They can blow but they can't suck!

the Minor bleed nipple will allow air back down the threads. This makes the one way valve a disadvantage as fluid can't come up the pipe so any suction will draw in air via the bleed screw thread.

Post by **alanworland** » Tue Aug 21, 2007 10:22 pm

When I bled my series mm I used a wd40 squirt tube inserted into the vent hole in the filler cap, I then applied about 8 psi air pressure to this, then went underneath and unsrewed the bleed screws one at a time until I had no bubbles (taking care not to empty the master cylinder) then lock up. No pumping, 'up' 'down' or 'ok up' 'ok down' works for me have used similar on various vehicles with dreat success, it might require a bit of making up of fitting(s) to get the air to the master cylinder top but well worth a try.

Post by **Orkney** » Wed Aug 22, 2007 8:07 am

Good idea that - wonder if its worth getting a spare filler cap and trying to wangle a car tyre valve to it using whatever handy. Sure would be a useful thing to have.

Post by **alex_holden** » Wed Aug 22, 2007 8:15 am

That's basically a poor man's Eezibleed, the advantage of the Eezibleed being that it automatically keeps the master cylinder topped up.

Post by **Orkney** » Wed Aug 22, 2007 8:42 am

Ah yes - but I'm poor

besides making things is fun. (nocked up a functioning 3ft wind turbine yesterday in 2 hours from just scrap)
Did wonder about the level as its a small cylinder, guess ive always confused an easybleed (never seen one) with those pipe jobbies with teh bearing one way valve on that goes on the bleed nipple.

Post by **dunketh** » Wed Aug 22, 2007 9:38 am

the Minor bleed nipple will allow air back down the threads. This makes the one way valve a disadvantage as fluid can't come up the pipe so any suction will draw in air via the bleed screw thread.

I've not had this problem myself, although all the pistons on the car are new ones I've put in. Maybe the newer ones have a finer thread?

I do tighten them up when the pedal is in the 'down' position though, purely because I'm paranoid about any air ingres.