The brake line from the master to the metering valve on my ‘70 W-30 4 speed (front manual disks) was dripping brake fluid from the master side of the line. I tried tightening the nut at the master to no avail so I ordered a new one from Inline. On the line that’s in the car now the nut at the metering valve is 7/16” and the nut at the master is 1/2”. The line that Inline just sent is 9/16” at the master and 7/16” at the metering valve. So it’s 1/2” mine vs. 9/16” theres. Before I take the old line out (the new one will probably not fit anyway) does anyone know what the correct size of these nuts is supposed to be ?

 

Just checked two KNOWN '70 ORIGINALS. Both lines have a 7/16" and 9/16" wrench/nut sizes across the wrench flats.

 

Checked two more known '70 originals.....same sizes on them as well.

 

Thank you Patton.

 

Mike, if you have any problem with the fit of the new brake line, a quick, but permanent, fix is to install a Brake Hydraulic Copper Gasket to seal your existing line.

Dorman makes them and you can get them at a local auto parts store such as NAPA.

Gary

 

Thanks Gary.