[Scw0440]

Getting my brakes finished up and running into an issue with the fitting size on the driver's side line. The proportioning valve I bought is linked below, new front brake lines for power disc from ss396(the right stuff) match the old ones currently on the car although the routing from the prop valve to the master cylinder will need some adjusting.


The issue is that the hole in the prop valve for the front drivers side is 3/8 and the fitting/nut on the driver's side line is 1/2 with the correct 3/8 on the hose side. Local parts store had adaptors to go from 1/2 to 7/16 then from 7/16 to 3/8 but I worry about stacking two adaptors and if the 3/8 line would seal well to the 1/2 adaptor.

Did I buy the wrong prop valve? Is there a correct line to buy with double 3/8 fittings instead of a whole new kit? Do I trust the two adaptors, or do I cut off the oversized fitting and put on a 3/8 fitting (never done before but shouldn't be too bad)? Any advice appreciated.


Prop valve: Proportioning Valve, Disc/Drum Brakes, Reproduction @ OPGI.com

 

[jcbrown]

You have the right prop valve the only problem is that all the fittings are of different sizes even though the tubing size is the same. When I plumbed my brake system I bought the right fittings from Summit. By your description I can't figure which tube you are talking about. If you can post a pic or give a better description I can tell you what p/n to buy. The auto parts store won't have these fittings.

 

[Scw0440]

You have the right prop valve the only problem is that all the fittings are of different sizes even though the tubing size is the same. When I plumbed my brake system I bought the right fittings from Summit. By your description I can't figure which tube you are talking about. If you can post a pic or give a better description I can tell you what p/n to buy. The auto parts store won't have these fittings.

Sorry, I'll try to re-explain and add pics. It's the 3/16 line from the prop valve to the front drivers side flexible brake line. The side connecting to the flex line has the correct 3/8 fitting but the side for the prop valve has an oversized 1/2" fitting. Both old and new lines have the same fitting.

I've had no luck finding a single fitting. Plus I'm worried that the 1/2" adaptor would be sized for a 1/2" line instead of a 3/16 line and would cause leaks due to not sealing properly. As seen in the first picture, I also have a very short piece that's 3/16 line with the same 3/8 and 1/2 fitting that doesn't go anywhere I can find. I could cut the 3/8 fitting off it that and the 1/2 from the driver's line and try my hand at flaring the driver's tube with the correct fitting. I guess I could also buy a 1 or two foot length of generic 3/16 line from O'Reilly if they make such a thing and bend it to fit.

 

[Shane Diffley]

Man so glad others have the same problems I have with 67 and had in 72. Finally got them all from summit. Checked everywhere in Houston. Epic fail. Learned never throw any removed fittings away. Also get the whole set up from summit. Get more then one fitting and more then one size.
on 67 we ordered the long brake line runs under driver side - I broke end off trying to straighten. Prop valve will not fit. Prop valve fitting hole too big. My pops in law is a machinist - so when line comes in we will solve that issue.
willwood on both and set backs every stinking time. Being a newbie it’s expected.

if it was easy everyone would do it. I keep telling myself. Build a resto mod they said it will be fun they said. Well I did two. Double the fun - not

 

[zeke67]

The stacked fittings wouldn't bother me. But I have also cut off the larger nut for smaller diameter tube of an old line and cut and re-flared the new line (old nuts only because I've never chased down the correct size new ones).

 

[jcbrown]

Sorry, I'll try to re-explain and add pics. It's the 3/16 line from the prop valve to the front drivers side flexible brake line. The side connecting to the flex line has the correct 3/8 fitting but the side for the prop valve has an oversized 1/2" fitting. Both old and new lines have the same fitting.

I've had no luck finding a single fitting. Plus I'm worried that the 1/2" adaptor would be sized for a 1/2" line instead of a 3/16 line and would cause leaks due to not sealing properly. As seen in the first picture, I also have a very short piece that's 3/16 line with the same 3/8 and 1/2 fitting that doesn't go anywhere I can find. I could cut the 3/8 fitting off it that and the 1/2 from the driver's line and try my hand at flaring the driver's tube with the correct fitting. I guess I could also buy a 1 or two foot length of generic 3/16 line from O'Reilly if they make such a thing and bend it to fit.



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Sorry, I'll try to re-explain and add pics. It's the 3/16 line from the prop valve to the front drivers side flexible brake line. The side connecting to the flex line has the correct 3/8 fitting but the side for the prop valve has an oversized 1/2" fitting. Both old and new lines have the same fitting.

I've had no luck finding a single fitting. Plus I'm worried that the 1/2" adaptor would be sized for a 1/2" line instead of a 3/16 line and would cause leaks due to not sealing properly. As seen in the first picture, I also have a very short piece that's 3/16 line with the same 3/8 and 1/2 fitting that doesn't go anywhere I can find. I could cut the 3/8 fitting off it that and the 1/2 from the driver's line and try my hand at flaring the driver's tube with the correct fitting. I guess I could also buy a 1 or two foot length of generic 3/16 line from O'Reilly if they make such a thing and bend it to fit.



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If you go to Summits website and type in Classic Performance PV-2 it will show you prop valve. If you scroll down it will show you the size inverted flare fittings you will need.

This proportioning valve is designed for use with front disc, rear drum brake applications and has two 3/8 in.-24 outlets for the front and one 9/16 in.-18 outlet for the rear. Inlet thread sizes are 1/2 in.-20 for the front and 7/16 in.-24 for the rear. Modifications may be required.

As you can see there are 4 different size tubing nuts. Allstar Performance sells the inverted flare fittings you need. The 3/8 in.-24 nuts are standard and you should be able to get them at an auto parts store. I plumbed my prop valve and had to go through this learning curve. If you have any more problems just keep posting here.

 

[Humberd]

Just cut the line as close to the flare as you can
Go down to your local parts house and if the don’t have just the flare nut you can buy a short made up
Line from them and cut the to salvage the nut
Put the new nut on and do a new double flare on your line.