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Need help w/ fitting sizes on 1975 Chevy m/c

Hey guys,

Need to bleed the master cylinder on my 1975 Chevy 3/4 ton van. My local auto parts store carries generic aluminum "hard" lines with the various flare fittings on them but I don't know which sizes thread into the output ports on the master cylinder. The employees there are totally clueless and they won't loan me a master cylinder so I can see which ones fit myself.

All I need to know are the flare sizes... the van uses power assist front disk/rear drum configuration with a dual master cylinder and the front brake fitting is a different size than the rear brake fitting.

Reply to
Miki Kanazawa
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Why not just do it all at the wheels?

If you remove the lines from the master, you will have air in the brakes anyway.

Maybe look for a bench bleeding kit. They are plastic fittings with clear hoses that fit in and refill the master at the same time.

If you need to bench bleed it, on lots of them, the pedal won't go down far enough to bottom the piston if they bleed that way, some don't, but you need to take some off the vehicle to do it right.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's

Miki Kanazawa wrote:

Reply to
Mike Romain

First thing NEVER, NEVER use aluminum, or copper for brake lines. Steel only for hard lines, and rubber/steel braid composition for flex lines. Some use teflon covered with steel braid, but do so at your own risk, as it is unapproved by DOT.

KenG

Miki Kanazawa wrote:

Reply to
KenG

I'll try the bench bleeding kit. I didn't think such a thing was available and figured I'd have to DIY with a coupla lines bent into a "U" going from the output port to the reservoir.

-M

Reply to
Miki Kanazawa

Our local auto chain, Canadian Tire, sell them. They also provide the kits with masters that need a bench bleed prior to installation.

A friend just got a strange one. He has the same vehicle as mine. Instead of the kit, it came with two plastic threaded plugs for the holes. He then had to do short 1/4 to 3/4" pumps very slowly and the sucker did empty all the air out.

I was surprised.

Mike

Miki Kanazawa wrote:

Reply to
Mike Romain

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