VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 1938 Brake Job - Tips?

Billy I had some of the same experiance yesterday getting the 53 ready for a tour, Mity Vaced, and mity vaced, not much came out ,so I filled master cylinder loosened the bleeder on rt rear wheel , pumped five times hard refilled MS and went back to mity vac, I had enough crud in the line that wouldn't vac out, I was by myself so I repeated. hooked up Mity Vac and filled master cylinder pumped 5 times got about 3/4 a bottle of dirty fluid then when it cleaned up used (used about a pint of new fluid) the mity Vac and now have a good full peddle, Had to adjust each wheel about three clicks on average.

The replacement brake lines arrived 8 days after ordering them. They look great!!

But... boy are the old ones a bugger to get off! Ouch... Had to take the two rear pieces off still connected together.

Here's my question: Does anyone make the brass tees for these? I had to really torque to get the lines off and I was afraid of breaking one of the three-way tees.

Billy, I know that Nationalchevyassoc makes them for 49-54 chevy cars, maybe they are the same. I assume you mean where the two rear lines hook together and the hose to the rear metal line hooks together.

Bill
I have found that using mityvac at wheels is not successful. Much better to have friend push brake pedal while you open bleed nipple then close nipple then release pedal. Also friend can top up master cylinder as fluid level drops.

TonyW, I found that a mityvac works ok, if not to perfection, with new rust free lines and good clean Dot 3 fluid, fill the master cylinder with your Mity Vac hooked up, pump out about a half a bottle of fluid, refill the master cylinder, pull a vacuum, crack the bleeder valve with a 3/8" inch thin boxend wrench that you place on the bleeder valve before attaching the Mity-vac hose.

I have thought about fabricating a pressure bleeder that screws into the top of the master cylinder with a quart reservoir for fluid and then pressureizeing it with a airline from the shop compressor...Do any of you have experiance with the one shown in the Chevrolet Shop Manuals?

I have a problem of finding that friend whenever I need one. I agree there isn't a good replacement for a human helper. I guess that was what God saw when Adam was alone in The Garden of Eden. of course that was also before Bra burning and NOW, and community property 401K's!!!!

I also have had good luck with the Mityvac.Good air tight connections are important -or is that vacuum (no air) tight.Prevents brake fluid from spilling on wheel etc.-removing paint.Also the color can be observed so you know when the "oldstuff" is drawn out of the line.

Bill - I've adjusted,rebuilt and bled the brakes on my 40 Chev many times since 1963. Here's what works for me. When I replace the linings, I adjust each shoe out until it is tight against the drum (wheel won't turn) then back it off until the wheel turns with a whisper from the drum drag. Softness in the brake pedal but some pedal indicates air in the system. Softness and pumping to get pedal indicates both air an lack of adjustment. To bleed the brakes requires 2 people. One on the pedal and the other to get brake fluid all over him. Over the years I have tried all kinds of gadgets to help bleed the brakes and none have worked as well as the fluid on the floor method. I do it just as you mentioned. LR, RR, RF, & LF. When I completely rebuilt the system, I refill it with fluid befor bleeding it I pump the pedal as hard as I 30 or 40 times. This seems to assist in forcing the air out to the wheel cylinders. Check the fluid a couple of times while doing this. Before I open the bleed valve each time I have the pedal person (usually my wife) long stroke the pedal 5 or 6 times before she holds it down and I open and close the bleed valve. I bleed each wheel until I see or hear air coming out of the bleed valve and then have a solid stream of fluid. I very seldom get much pedal until the last wheel is bled (left front). Just a slight amount of air will let the pedal go all the way to the floor. If air has been introduced into the system you will usually get some air from each wheel cylinder. Every time I've given up on a wheel and quit bleeding because I thought there was not any air I've had to go back and bleed it until I did get air out. Good Luck, Mike Deeter

Gee thanks everyone... It seems that after all these years, it still takes two to tango.

Will let you know how it goes now... by the way, when I removed the master cylinder, I noticed that some of the wiriing is frayed and has some bare strands showing... first saw it around the stoplight switch, but also could see bare wires going up to the headlight dimmer switch. How much effort should I spend on THAT?

While you are there FIX what is bad!

Billy
Pressure bleeder from master cylinder is the easiest way then comes the offsider. I have also successfully bled brakes by fitting a hose to the nipple and ensuring it is raised above the it opening the nipple and quickly pumping the pedal several times myself.
Using the mityvac draws air past the nipple threads giving false indication.
I also agree with the stainless sleeve in the master cylinder, next time you need to rebuild it you will only need get the rubber parts.
Tony

FINAL REPORT

All is done. Helgy and I finished the job today! Bled all of the brakes using the "two man" method. Also shortened the hose to about 12" so that I could keep it full of liquid all of the time and not have air move back to the bledder valve.

Got all four wheels done and the pedal would only come up about an inch off the floor... dang!!! What was wrong? Was there air in the new wheel cylinders? In the New Master cylinder? in the new lines?

Helgy said, "why don't we go around and adjust all of the shoes again?" -- not something that I was real eager to do, since we hadn't done any driving since I installed the shoes and adjusted them. But we decided to do it anyways.

Got the first rear done... tightened it about 15 clicks and backed off 4 --- did this to both the front and rear adjustments on each cylinder. Then the other rear, same number, tighten 15, loosen 4.

Checked the pedal --- no change... still one inch off the floor.

Then went to the left front. Tightened 12, backed off 4 clicks... arghhh! Not much difference, but it was becoming apparent that I had been too easy on my initial adjustment.

Started the final wheel, the right front. Tightened the forward cap 30 clicks... Helgy asked "Are you going the right direction?"... yep, I was.... went another 25 clicks before the shoe began to drag!!! :eek: Finally, ended with 60 tightening clicks and backed off 4.

Helge jumped in and pushed the pedal and exclaimed... "We've got LOTS of pedal now!!!"

Rolled the car out, took it up the hill from my house. Coming back down the hill, I purposely locked up the tires, skidded rubber and the steering wheel never flinched either direction!!! Cool!!! :cool2:

So, now I'm done. After 3+ years, I have my car on the road with really good brakes!!! And I'm a little smarter, too. I know that if you bleed the lines and don't get any air, then you need to adjust the shoes and close up the gap, no matter how close you THINK they already are!!! Sure is great to have someone else around to help you break through your mental barriers!!!!

Thanks Helgy!!!

Thank you all for this great site. I replaced all my wheel cylinders last night, flushed and had great breaks.

Thank you again.

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