Master cylinder/brake line fitting size diff!!
Thread Starter
Drifting
Joined: Sep 2006
Posts: 1,986
Likes: 21
From: Columbus MN
Master cylinder/brake line fitting size diff!!
I finally got a couple of hours to work on my '80 today, so I thought I'd mount my new master cylinder and brake pads, fill with fluid, and bleed the lines. Sounds simple, but I hit a glitch almost immediately.
I mounted the new chrome plated master cylinder to the booster - no problems, simple. Connecting the brake lines was next, but no joy. The old fittings are 1/2" and the master cylinder takes 3/8". What's with that? When were 3/8" fittings used? When did they start using 1/2"?
I'm not keen on switching the brake lines to 3/8" fitting. I don't even know if that's possible. The brake lines are 3/16" diameter. I'd have to cut the flair off the brake lines without getting metal in the line, slip new fittings over, and reflare the lines.
The other option is to get a new m.c. with correct fitting size. Anybody want to buy a brand new chrome m.c. with 3/8" fittings?
I mounted the new chrome plated master cylinder to the booster - no problems, simple. Connecting the brake lines was next, but no joy. The old fittings are 1/2" and the master cylinder takes 3/8". What's with that? When were 3/8" fittings used? When did they start using 1/2"?
I'm not keen on switching the brake lines to 3/8" fitting. I don't even know if that's possible. The brake lines are 3/16" diameter. I'd have to cut the flair off the brake lines without getting metal in the line, slip new fittings over, and reflare the lines.
The other option is to get a new m.c. with correct fitting size. Anybody want to buy a brand new chrome m.c. with 3/8" fittings?
Le Mans Master
Joined: Apr 1999
Posts: 6,134
Likes: 46
From: Raleigh North Carolina
I finally got a couple of hours to work on my '80 today, so I thought I'd mount my new master cylinder and brake pads, fill with fluid, and bleed the lines. Sounds simple, but I hit a glitch almost immediately.
I mounted the new chrome plated master cylinder to the booster - no problems, simple. Connecting the brake lines was next, but no joy. The old fittings are 1/2" and the master cylinder takes 3/8". What's with that? When were 3/8" fittings used? When did they start using 1/2"?
I'm not keen on switching the brake lines to 3/8" fitting. I don't even know if that's possible. The brake lines are 3/16" diameter. I'd have to cut the flair off the brake lines without getting metal in the line, slip new fittings over, and reflare the lines.
The other option is to get a new m.c. with correct fitting size. Anybody want to buy a brand new chrome m.c. with 3/8" fittings?
I mounted the new chrome plated master cylinder to the booster - no problems, simple. Connecting the brake lines was next, but no joy. The old fittings are 1/2" and the master cylinder takes 3/8". What's with that? When were 3/8" fittings used? When did they start using 1/2"?
I'm not keen on switching the brake lines to 3/8" fitting. I don't even know if that's possible. The brake lines are 3/16" diameter. I'd have to cut the flair off the brake lines without getting metal in the line, slip new fittings over, and reflare the lines.
The other option is to get a new m.c. with correct fitting size. Anybody want to buy a brand new chrome m.c. with 3/8" fittings?
2 cents.
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
The front/rear fittings are different sizes on my '69, also. They match up with the fittings at the proportioning block. They were done this way at the factory so the assembly workers couldn't mix up which line goes to the proper (front or rear) master cyl. reservoir.
Intermediate
Joined: Sep 2004
Posts: 43
Likes: 0
From: Como Lake - Italy
I put a Wilwood master cylinder and after spending some time trying to screw the wrong fitting I realized I was not drunk but front and rear are different!
the proportioning valve has different sizes as well!
the proportioning valve has different sizes as well!
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