Author Topic: 66 brake proportioning valve rebuild  (Read 3473 times)

alexgt350h

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66 brake proportioning valve rebuild
« on: April 16, 2021, 05:23:39 PM »
Who do you use to rebuild 66 Shelby , brake proportioning valve?
Brent

DRGT350

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Re: 66 brake proportioning valve rebuild
« Reply #1 on: April 16, 2021, 05:43:10 PM »
Brent -

try   White Post Restorations they did one for me and no leaks ..- https://whitepost.com/

They did one for me - tell them not to stamp it "WP" on the top of it like they did to mine,  and also tell them if you are using DOT 3 or silicone fluid..

Dave

alexgt350h

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Re: 66 brake proportioning valve rebuild
« Reply #2 on: April 16, 2021, 05:53:40 PM »
Thanks, was also told about SSBC USA out of NY.
That's the old Stainless Steel Brake Corporation.

Bob Gaines

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Re: 66 brake proportioning valve rebuild
« Reply #3 on: April 16, 2021, 07:15:53 PM »
Brent -

try   White Post Restorations they did one for me and no leaks ..- https://whitepost.com/

They did one for me - tell them not to stamp it "WP" on the top of it like they did to mine,  and also tell them if you are using DOT 3 or silicone fluid..

Dave
It is my understanding that whitepost will not assemble the proportioning valve with silicone like it needs to be if using silicone in your brake system. For Dot 3 or 4 that is not a problem but if using Dot 5/silicone the regular brake fluid used to assemble the proportioning valve may cause the two non compatible fluids to gel . I do not think they will warranty any problems if they know you use silicone. FYI I think silicone is the way to go on a pleasure driven or show car.
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

CharlesTurner

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Re: 66 brake proportioning valve rebuild
« Reply #4 on: April 16, 2021, 09:04:01 PM »
Have had 2 white post rebuilt valves start leaking when used with silicone over the past couple years.

Try Mark Frappier: racedirteater@yahoo.com
Charles Turner
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alexgt350h

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Re: 66 brake proportioning valve rebuild
« Reply #5 on: April 16, 2021, 10:05:38 PM »
Will do, thanks!

6s855

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Re: 66 brake proportioning valve rebuild
« Reply #6 on: April 17, 2021, 03:40:42 PM »
Apple Hydraulic in MY did mine. No silicon dot5. Don't forget to replace the brass port seats.

6s1640

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Re: 66 brake proportioning valve rebuild
« Reply #7 on: April 18, 2021, 12:49:45 AM »
I had wheel cylinder rebuilt by White Post and they do not warranty with Silicone brake fluid as well.

Cory

Bob Gaines

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Re: 66 brake proportioning valve rebuild
« Reply #8 on: April 18, 2021, 02:34:53 AM »
I had wheel cylinder rebuilt by White Post and they do not warranty with Silicone brake fluid as well.

Cory
If you wanted to run silicone you would have to take the rubber seals out and clean rubber along with cylinder bore with rubbing alcohol or similar . You then reassemble using silicone to lubricate the rubber and bore. It is very easy to do on wheel cylinders if you are so inclined . Not as easy to do on a proportioning valve .
Bob Gaines,Shelby Enthusiast, Shelby Collector , Shelby Concours judge SAAC,MCA,Mid America Shelby

whiteykr

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Re: 66 brake proportioning valve rebuild
« Reply #9 on: April 18, 2021, 02:47:22 AM »
+1 on what Bob said. I rebuilt mine with a NPD seal kit. The one seal is hard to get on . Make sure the cylinder bore is pit free and dip all of the seals in silicone dot 5 . I am going on 1 yr. with no leaks .we will see if it stays leak free.

6s1640

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Re: 66 brake proportioning valve rebuild
« Reply #10 on: April 18, 2021, 03:41:54 AM »
I had wheel cylinder rebuilt by White Post and they do not warranty with Silicone brake fluid as well.

Cory
If you wanted to run silicone you would have to take the rubber seals out and clean rubber along with cylinder bore with rubbing alcohol or similar . You then reassemble using silicone to lubricate the rubber and bore. It is very easy to do on wheel cylinders if you are so inclined . Not as easy to do on a proportioning valve .

Hi Bob,

IIRC, I stayed with the DOT 3.  Thanks for the tip.  That would have been my guess what to do if converting to Silicone.

Thanks

Cory

shelbydoug

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Re: 66 brake proportioning valve rebuild
« Reply #11 on: April 18, 2021, 08:22:40 AM »
I'm not sure why there is so much issue with the silicone fluid?

I switched over 25 years ago by just draining and bleeding the system. Nothing was disassembled.

Still no leaks or failures.


I also remember when we didn't need to do Snell numbers on the helmets and we could take passengers on the track at unlimited speeds running on street tires without W speed designations.


This paranoia that is prevalent today has it's roots somewhere in the past.

I don't need a comity of lawyers advising me on where and how I need to and can take a dump. You folks do what you want. I'm not playing this game. It's just some kind of a kill the party anyway you can train of thought if you ask me.

Probably starts with Alan Dershawitz in Harvard Law School in order to establish who is King S hit and who isn't. Even my Kindergarten class wasn't this bad.
68 GT350 Lives Matter!

NC TRACKRAT

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Re: 66 brake proportioning valve rebuild
« Reply #12 on: April 18, 2021, 09:04:05 AM »
FWIW, about four or five years ago, I had White Post re-build a proportioning valve for 6S1467 because the original continued to leak at one of the fittings.  (Like shelbydoug, I changed over to silicone brake fluid when we purchased the car about 25 years ago)  I haven't lost a drop of fluid from the valve and the brakes work just fine.  I guess the Good Lord looks out for dumb animals! :)
5S071, 6S1467

shelbydoug

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Re: 66 brake proportioning valve rebuild
« Reply #13 on: April 18, 2021, 10:02:34 AM »
FWIW, about four or five years ago, I had White Post re-build a proportioning valve for 6S1467 because the original continued to leak at one of the fittings.  (Like shelbydoug, I changed over to silicone brake fluid when we purchased the car about 25 years ago)  I haven't lost a drop of fluid from the valve and the brakes work just fine.  I guess the Good Lord looks out for dumb animals! :)

I did five cars with the same no issues. I always get the impression that the "doomsayers" are just soliciting business.

As far as being a "dumb animal", it depends on who is rating me. I've been called a "survivor" which I suspect isn't necessarily a negative comment, just perhaps a caution to those who would openly oppose me considering the list of those that did and are no longer classified as living. That list is surprising but yet somewhat gratifying to me, but is extensive these days? ;D

As Bill Murry's character in "Tootsie" said, "no one would call you stupid to your face!" I think applies to me?

Even so, it's like I have my own "Praetorian Guard" of which I have no control over? People just "disappear" into the obituaries and it had nothing to do with me.  Very strange?  8)
« Last Edit: April 18, 2021, 01:12:37 PM by shelbydoug »
68 GT350 Lives Matter!

sg66

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Re: 66 brake proportioning valve rebuild
« Reply #14 on: April 18, 2021, 10:40:22 AM »
I've also been using DOT 5 for 25+ years and had White Post rebuild mine 5 years ago. Last spring when I took it out of storage, there was a puddle of brake fluid on the floor of the garage. Turned out to be from a leak past the rear o-ring.

More details: http://www.saacforum.com/index.php?topic=10452.msg89915#msg89915

This year, everything is still dry so maybe my fix with known EPDM and slightly thicker o-rings worked. Looking back now, part of the testing I did last year did show some minor swelling of Nitrile o-rings in DOT 3 when I tested against DOT 5. Conventional wisdom has been that swelling is bad however for leaks past the rear o-ring, I would argue that swelling is good. I had also found signs of moisture in my valve when I opened it and now wonder if freezing temperatures caused that to expand just enough to push past the o-ring.

If it ever leaks again, I'll consider switching over to Castrol SRF which claims:

"It is miscible with all conventional fluids meeting the US Federal Standards FMVSS 116 DOT 3, DOT 4 and DOT 5.1, ISO 4925 and current SAE J1703. This means that changing the brake system to Castrol SRF is easy. Drain and flush out the conventional brake fluid with Castrol SRF then top up the system with Castrol React SRF Racing. Although Castrol React SRF Racing is miscible with conventional brake fluids, topping up Castrol React SRF Racing with conventional brake fluids will reduce the benefits of the product."

https://www.moreheadspeedworks.com/product/castrol-srf-1l/

Keep in mind that you can not drain and flush K/H calipers unless you remove them, turn them upside down and let the old fluid drain out. The bleeder only purges air and fluid at the top of the caliper.
« Last Edit: April 18, 2021, 10:48:15 AM by sg66 »