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Tue Jan 11, 2005 7:52 am

Hey guys, I read somewhere that you should bench bleed your master cylinder when you buy a new one. As I am in the middle of a pan off and the body is not on my pan right now, I would like to do this properly. I have all new steel and rubber lines, 4 new wheel cyls, and a new master cyl. I can hook up the resovoir (sp?) to the master cyl on my work bench and all that, but I do not know exactly how to go about it. I thought I saw a tech article on the web somewhere the other day but I can't seem to find it again.

Does anyone know where I could find online tech help or would anyone care to tell me how to go about bench bleeding my master cyl?

Also, I am accepting general advise on the entire braking system as it is all brand new and I don't want to screw anything up. I want the car to go, but I want it to stop even more!! :D

Tue Jan 11, 2005 7:59 am

what year car?

For a 69and later (IRS), Ghia front disc with Type 3 rear drum are a bolt on upgrade.

That's what i'm running on my 74.

Tue Jan 11, 2005 8:19 am

Oh sorry, I guess I should have mentioned it's a 60.

Tue Jan 11, 2005 10:32 am

I used a broken piece of brake line screwed to the inlet from the resi and stuck the broken end into a big bottle of fluid. With the MC in a vise I pushed the brake pedel end until the fluid coming out the outlet ports was nice and clean with no bubbles. Then I carried it out to the car to install.

Thu Mar 10, 2005 10:56 pm

So lets say I didnt know you were suppost to do this, and I didnt bleed mine before I put it in. I cant get any of my brakes to even hit, and no good or even alright pressure out of the brake system...did I reuin the new one I just boght?

Thu Mar 10, 2005 11:05 pm

Rusted Radio , you did not ruin the new master by not bench bleeding it . A VW master doesn't need to be bench bleed, the resevoir is high enough above that you can gravity bleed it . First fill the res , then crack the lines at the master , tighten them as they begin to leak , then do the rears , then the fronts . Make sure the car is sitting level when doing this and keep the res full . After this you can bleed the brakes with a buddy or a Mity Vac . Don't forget to check the pedal stop and pushrod for proper adjustment . TROY

Fri Mar 11, 2005 7:13 am

T-ROY is correct.

Mon Aug 25, 2008 4:50 pm

My new master cylinder came back without proper pushrod adjusting. It bend the pushrod to about a 45 degree angle. I removed it, whammered it flat and reinstalled it the pin. No fluid must have been getting to part of the MC as my brakes dragged and i horribly stalled out. So I backed the re-flattened push rod pin out (of course it turns tight as heck now because it's not perfectly straight anymore) and it's better but still not so great; at high rpms I've had it cough and seemingly almost catch after a long brake.

My question: just how far back can I pull that adjusting pin? As I counter it away from the MC, that is? Any advice?

Tue Aug 26, 2008 5:41 am

peacejones wrote: My new master cylinder came back without proper pushrod adjusting. It bend the pushrod to about a 45 degree angle. I removed it, whammered it flat and reinstalled it the pin. No fluid must have been getting to part of the MC as my brakes dragged and i horribly stalled out. So I backed the re-flattened push rod pin out (of course it turns tight as heck now because it's not perfectly straight anymore) and it's better but still not so great; at high rpms I've had it cough and seemingly almost catch after a long brake.

My question: just how far back can I pull that adjusting pin? As I counter it away from the MC, that is? Any advice?

REPLACE THAT BENT PUSH ROD A.S.A.P.!! I wouldn't drive the car until it is replaced. This is all that is between you and crashing into something. Since it has been bent, it has a weak spot where it may be ready to bend again when you need it most.

Once you get your new rod, then install it and adjust it as needed.

Tue Aug 26, 2008 6:23 am

peacejones wrote: I removed it, whammered it flat and reinstalled it the pin.

:shock: Did you go to the school of auto repair for rednecks? Not trying to disrespect you, but it is just common sense to replace it. The only thing that can be fixed with a hammer is a dent in the body :D

Tue Aug 26, 2008 11:19 am

Whammer? Haha, I kinda like that one.

I didn't have to bench bleed when I installed a dual circuit in my '66. Just hook everything up, start at the furthest wheel away and have at it.

Now, I don't know how the earlier cars are set up, but I know this next piece applies to the 66 and 67 for sure. Late models are okay, I think, because the reservoir is on the side of the luggage compartment. My biggest problem with the bench bleed is that sure, you fill it and bleed it and such, but then you have to take the reservoir line off in order to reconnect it back in the car. The lines go through the front apron to the reservoir, which is behind the spare tire. So you are still going to cough some air through when you disconnect and reconnect again. That's why I didn't bench bleed mine.