Chevy Nova Forum banner
1 - 4 of 4 Posts

· Registered
Joined
·
1,197 Posts
Discussion Starter · #1 ·
I have a combo valve but the port on the back for the rear line does not fit, I believe the line is 1/4 but don't know about the nut size, would it be the same? The threads on the combo valve are 9/16, if I was to try and connect an adapter or something between the 2 would it leak?
 

· Registered
1974 Nova, 1977 Nova
Joined
·
1,800 Posts
Hi Vnova,

You're right, the combo valve rear outlet has 9/16"-18 thread and takes a 1/4" line.

The "standard" flare nut size for 1/4" line has 7/16"-24 thread. So you need to use either a special nut with the oversized 9/16" thread or an adapter fitting.

I didn't want to cut and re-flare the rear brake line when I converted my 74 from drum to disc brakes so I used a Weatherhead #7908 adapter fitting. These adapters are made just for changing thread sizes on inverted flare connections so it seals up perfectly ... no leaks.
 

· Registered
Joined
·
1,197 Posts
Discussion Starter · #3 · (Edited)
Hi Vnova,

You're right, the combo valve rear outlet has 9/16"-18 thread and takes a 1/4" line.

The "standard" flare nut size for 1/4" line has 7/16"-24 thread. So you need to use either a special nut with the oversized 9/16" thread or an adapter fitting.

I didn't want to cut and re-flare the rear brake line when I converted my 74 from drum to disc brakes so I used a Weatherhead #7908 adapter fitting. These adapters are made just for changing thread sizes on inverted flare connections so it seals up perfectly ... no leaks.
Thanks. I don't wanna cut into the line either.

Did you buy yours online or do you know if Napa carries this fitting?
 
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top