Brake Master Cylinder port sizes
 

Hey folks I have a question. I have a 1970 Long bed F100 with regular power brakes. (vac booster and master cylinder) I ordered a new set of stainless brake lines from a restoration company named Inline tube. Beautiful product but I'm having a problem with the fittings that go into the master cylinder. I ordered a restoration master cylinder from Blue Oval Truck parts. The port sizes are 9/16 front and 1/2 rear. That is the same size as the ports currently on the truck. The new lines however are 9/16 front and 3/8 rear.

The folks that made the lines told me I was using a master cylinder for manual brakes not for power brakes and their lines were correct. I can't find a master cylinder for a 1970 Ford that has a 3/8 rear port.

Has anyone out there had any experience with this? I can always use an adapter but I want it to be right. Details!

Thanks!

What year is the M/C that you bought from Blue Oval? Some of the repro parts sellers are clueless. 1967 M/C's are ONE YEAR ONLY as the brake (and clutch) pedal are also one year only!

1968/72 F100's with manual brakes use different M/C's than with P/B's / 1968 F100's with P/B's use a different M/C (C8TZ-2140-F) than 1969/72's (C9TZ-2140-H) w/P/B's.

1968/72 F250 2WD's and F350's with optional power disc brakes use a specific master cylinder. So, what's the application for the M/C that Blue Oval sold you that came from a local autoparts store?

If I'm reading this correctly, there is a brass adaptor that screws into the master and the brake line screws into that. OR maybe I reading it wrong.

Genuine Ford M/C's come with the brass fittings that the brake lines thread into.

Gypo "autoparts store replacment fitz-all" M/C's may not, as the fittings differ from one M/C to another. They assume the old fittings will work on their new M/C. Lotsa luck!

Ford did not sell steel brake lines, only came on new vehicles. Long suffering partsguys had to make new lines using a tubing bender, bulk tubing/nuts/ferrules.

I wonder what the aftermarket steel lines are based on, considering there's no parts catalog applications, no new steel lines?

You have to wonder if they pulled steel lines off a truck in a boneyard, made new lines from it...then assumed that all trucks of the vintage the old lines came from...used the same lines.

Yeah, at the time, i had a hard time finding replacement lines, SO I just made my own. Pain in the butt but at least I know they fit right.

Actually the MC from Blue Oval is supposed to be the correct one for that year however they only carry one for both manual and power brake applications. The port sizes on the MC from Blue Oval are the same ad the MC that is currently on the truck. Inline Tube is actually re-making that one line with a fitting on it to match the MC. They claim they follow factory schematics to bend all their lines with a computer guided tubing bender. It's a really nice product and everything lays perfectly. I just wanted to make sure everything was correct.

Thanks!