Brake bleeding problem

[Steve-w5bag]

Hi TVR nuts,

Hoping someone can help me with this one, I have a Griffith 500 1996.

I've had to change the rear flexible brake hoses for the MOT, I've fitted the new ones ok but I'm having trouble bleeding the brakes, I've topped up the master cylinder with new fluid but i can't get the fluid to pump through, it won't pump though from the brake pedal, I also have a vacuum pump and this won't pull the fluid through either, I've never had this problem before, hope some one can help

Thanks
Steve

[phillpot]

Try the front brakes.

Not a problem I've had but have read of owners having similar issues I think caused by master cylinder piston moving further than usual and sticking.

[Steve-w5bag]

Thanks for that Philpot,

That may be the issue, if the master cylinder is stuck or travelled too far, how do i fix this?
or do i have to replace the master cylinder?

Thanks

[phillpot]

You may be able to strip and rebuild with new seal kit, or replace


Access, as you may well know, is dreadful!

[Loubaruch]

I had a similar problem while replacing both rear callipers, one side was fine the other would not bleed it was actually a blocked bleed nipple, faulty from new.

Before delving into your master cylinder check that the front ( suggested above) and the other rear calliper are having the same problem

[Steve-w5bag]

Thanks All for the comments, its appreciated,

The bleed nipples as far as i could see are ok but i will double check.
I will try the front again as well

But last night i couldn't get any fluid through to either of the rear wheels, the master cylinder reservoir is full, but the fluid level does not go down at all, which is why I thought there was an issue in the master cylinder.

I'm going to get a gunson eezy bleed and use some pressure in to the top of the master cylinder to see if it pushes the piston back in, then bleed the master cylinder next before going back to the wheels.

If anyone else has any comments they are welcomed.

When i fix it, i'll post back how i did it in case it helps someone else

[Steve-w5bag]

I'm pleased to say I've got the brakes working now.

The gunson eezibleed did it, I connected it up started with the rear then the front, I used slightly more than the 20psi max which it said in the instructions and it pushed the fluid through without having to mess with the master cylinder at all, so pleased it worked as I was dreading removal of the master cylinder.

Thanks for all the comments, I got there in the end and the comments did help

[blaze_away]

I'd check to verify the brakes actually work. The master cylinder has two separate fluid lines 1 front and 1 to the rear. From memory the m/c piston has 2 seals 1 for front 1 for rear. Maybe the rear feed seals n the m/c aren't working

[steviegtr]

The same as my Chimaera. Which I recently renewed all the brakes + fitting Brembo's to front. You may have seen my Youtube channel doing all the work. Anyway the master cylinder is as someone already said is called a Tandem cylinder. Front brakes one circuit & rears the other. If you have only replaced the rears & need to bleed. This cannot be done by pressing the brake pedal. Because the front brakes are sealed with no air so trying to press the brake pedal will send very little fluid to the rear. The only pedal movement you would get is till the front pads are hard against the disc. Not far. The way you did it is correct with pressure bleeding.
Steve.

[phillpot]

On that logic, if you have air in all four corners and bleed, as generally recommended, the rears first you will have issues bleeding the fronts because rears are now functional?