63Hawk brakes bleed problem.

[BrianC]

i Rebuilt front wheel calipers, replaced pads. Bleed both sides, however there seems to be air in the system. At a stop i have to pump once to achieve full pedal. In some models there is a bleed on the slave cylinder however on the Hydrovac there isn't. How do i bleed the air from the master cylinder. I am getting clear fluid and no air from the calipers.

[StudeRich]

Hydrovac Brake Boosters as used on Disc Brake Hawks have two bleeder screws, one on input side one on output side.

Having to pump the pedal up, often can mean the brakes are out of adjustment. Have you you adjusted the Rear, front and rear shoes?


StudeRich at Studebakers Northwest -Ferndale,WA

[BrianC]

I replaced the front pads,they seem to be running good on the disk and releasing correct. I never adjusted the rear shoes. There aren't any bleeder screws on the input or out put sides of the Hydrovac, and my problem is i can't get the line ends loose. This is the same hydrovac in the 1962-64 shop manual, page 42. There aren't any bleed screws on the input or output. The hydrovac unit has one bleeder on the top, the Power brake unit (which is different) has two, one on top and one on bottom.

[studebaker-R2-4-me]

Bleed the brakes systematically. Furthest away to the closest. So, Rear passenger, rear drivers, front passenger, front drivers, then the Hydrovac. On my disk braked Hawk's hydrovac there is only one bleed valve on the top.

Best of luck

Allen


1964 R2 GT Hawk

1963 Daytona Convertible
Oakville, Ontario.
Hamilton Chapter
See you in Cedar Rapids Summer 2009

[StudeRich]

You got me confused here, isn't the Power Brake Unit = to the Hydrovac Unit? Is your car the only one that has TWO? [?]

Sounds like you need to adjust those rear brakes and maybe remove a plug and replace with a bleeder screw or something, as they all have to have one as Allen said.

[studebaker-R2-4-me]

Rich,

I think Brian is trying to say "Drum Brake" hydrovac's have two bleed valves and Disk brake hydrovac have one bleed valve.

Allen

[BrianC]

That's correct, the drum brake Hydrovac has two bleed valves. Yhe DisK has one.

[StudeRich]

What REALLY matters here is this: "Sounds like you need to adjust those rear brakes and maybe remove a plug and replace with a bleeder screw or something, as they all have to have one as Allen said."

[BrianC]

Rich, i think that you misunderstood me. There are no "INPUT" OR "OUTPUT" BLEEDERS", just the vacuum bleeder on the top of the slave cylinder. I wanted to know if this bleeder acts for both while bleeding?? I wasn't sure if opening this one would have some detremental affect on the control valve or diaphram or anything else for that matter, even though it is done with the engine off. These are MERCEDES engineered units, they're complicated and easy to screw up. The manuals don't tell all. I'm quite sure that at some point in time, Studes were new to you to. I'd rather err on the side of caution.
thanks

[GTtim]

Brian, the bleeder on the Hydrovac is for getting the air out of the brake lines/slave cylinder. It won't screw up the booster when you open it. Treat it like a wheel cylinder bleeder to get the air out. I have found that sometimes this one needs to get bled first to gain sufficient pressure to do the rest.

Tim K.
'64 R2 GT Hawk

[jimmijim8]

Get the air out of the booster first. jimmijim

[studebaker-R2-4-me]

Brian, these guys are right. Do the Hydrovac first and go back to it at the end. Go down to your local hardware store and get two feet of clear tubing to stick over that nipple and stick the tube in an partially full clean water bottle (Brake fluid). I usually drill a hole in the plastic top and put the tube through it. It will save your paint job under your hood and on your hydrovac. With this method you can see the air coming out too.

I can't tell you how many times I've bled my braking system on my Hawk. I've gone through 2 Hydrovacs with a rebuilt unit that would not quite leaking. Good luck.


1964 R2 GT Hawk

1963 Daytona Convertible
Oakville, Ontario.
Hamilton Chapter
See you in Cedar Rapids Summer 2009

[BrianC]

Excellent info. Thanks so much. I'm sure that'll do it.
BrianC

[BrianC]

Very handy idea about the water bottle. It worked great. Thanks again.

[DEEPNHOCK]

Harbor Freight just had a brake bleeder kit on sale last weekend...
Jeff[8D]

quote:Originally posted by studebaker-R2-4-me

Brian, these guys are right. Do the Hydrovac first and go back to it at the end. Go down to your local hardware store and get two feet of clear tubing to stick over that nipple and stick the tube in an partially full clean water bottle (Brake fluid). I usually drill a hole in the plastic top and put the tube through it. It will save your paint job under your hood and on your hydrovac. With this method you can see the air coming out too.

I can't tell you how many times I've bled my braking system on my Hawk. I've gone through 2 Hydrovacs with a rebuilt unit that would not quite leaking. Good luck.