The Stovebolt Site Forums The Parking Lot Big Bolts 1948 big bolt - Help!-- poor brakes

I have a '48 big bolt and have gone through the brakes--honed and kited wheel cylinders and master cylinder. New shoes on rear and fronts were good. Bled twice until I got a good fluid flow from each cylinder. Now when I press the brake pedal it goes to 1/2" of the floor. A second press of the pedal and I've got good firm brakes three inches off the floor. Do I need to bleed again?

How are you bleeding? Sometimes gravity bleeding and just pumping with the master cylinder isn't enough. Try vacuum bleeding with a pump at each wheel. Ya might have an air bubble trapped. Was the master cylinder off? was it bench bleed?

Hy bens48bigbolt, are your brakes adjusted up correctly?

olddaze-
I'm gravity bleeding. I've tried the vacuum and had problems with the tool. Yes the master cylinder was removed and no it wasn't bench bled.

3B- I've adjusted the brakes until I hear a slight drag then back them off a bit ( according to shop manual).

Gentlemen----Thanks for the tips. I'll recheck everything.

If it's a stock '48 master cylinder there is no need to bench bleed it. It sounds just like you still have air. Get a friend or you girl friend to pump up and hold the breakes for you and do it in the sequence that's called out in the manual. Watch the level closely, you will probably have to refill it a half dozen times when you bleed the brakes out.
Your manual adjustment sounds correct, I genereally lock up the wheel with the manual adjustment and back each adjustment off by three to five clicks.
Denny G

If you have a high spot in your lines you may never get the air bubble out with just pumping. The air bubble will just move back and forth with each push and release. You'll have to master using the vacuum pump. Once mastered, you'll never go back to pumping.

You have a "Big Bolt". How big? Does it have a hydrovac unit in the brake system? If it does, did you following the bleeding procedure in the Shop Manual?

I agree with Denny. Lock them up then back them off equally. The "light dragging" method was never enough for me. Btw speedbledders make bleeding simple, IMO.

Gentlemen,
Thanks for the great help. I went back and re-adjusted each brake drum and now I have "throw ya' through the windowshield" brakes.

801curt- I've never heard of a speedbledder.??--- I have heard of a pressure bleeder and a vaccum bleeder. Tried the vaccum didn't work--no access to a pressure bleeder.

Thanks again everyone.
Ben

3B and Mr.Lederman have nailed it

I got a simple pressure bleeder from summit racing. Bet HF has one as well. Worked well for me when I did my bolt's brakes. Didn't cost a bunch so don't feel bad about it setting on the shelf for the next time.
glad you are making progress.