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Options for 1969 Proportioning Valve

8K views 37 replies 10 participants last post by  MrsPib 
#1 ·
Hey all,

Long-time lurker, first-time poster here.

I have a 1969 with the 302 and factory power disc/drum combo. Recently, my entire brake system decided to kick the bucket - one failure at a time.

Most everything is going back together well enough (New master cylinder, rebuilt Midland booster, steel braided and stainless brake lines), but my proportioning valve seats are scored and leak like a sieve. Looking at my options, it looks like 1.) Used from a junkyard (Classic Cougars), 2.) Scott Drake reproduction (has scathing reviews on CJ Pony Parts) 3.) Aftermarket (most of which say the brake lines will need to be modified, but I just ordered the complete stainless kit, and I'm not too excited about bending and hacking them up to make 'em fit).

My questions are
- What aftermarkets have you been happy with, and did you need heavy modifications to fit, or just an adapter or 2? Can factory proportioning valve seats be machined smooth again? Anyone have experience with trying that route? Would you even touch a junkyard unit?

I appreciate any advise you all have. I'm tired of having just a brake-fluid-soaked lump in the garage.



 
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#2 ·
The stainless steel lines may be the problem ? They don't seat or seal with just the normal procedure. Tighten loosen and tighten again you will notice with each re-tighten the nut travels further. Repeated seatings are required to get the harder steel to seat/seal. Brian
 
#3 ·
Good to know! Unfortunately, my stainless lines haven't arrived yet, so this damage is from my learning curve with a double-flare tool on traditional hardline. Now that the valve is damaged, I'm not sure I could get anything to seat properly. Would the stainless lines cut a new seat in the valve if tighten enough? That sounds like a may end up stripping the brass threads though.

I don't know - I'm at a loss at this point. Trying not to break anything else while putting it back together right is my goal! Any suggestions on how to repair or replace that valve would be greatly appreciated :)
 
#6 ·
I saw that WCCC has one listed as a 'wrecking yard item', with a video on how to rebuild it, but I didn't see anything on their site about if they offer rebuilt ones or not.

If going with a used one, would you recommend WCCC? Do they give it a pretty good once-over to look for damage? Or do you have another source you like more? I wouldn't be opposed to a rebuilt one either, but I couldn't find a source that offered them.

And of course, any solutions to fix my current one, I'm all ears. That's $150-200 I could definitely put elsewhere on the Mustang :)
 
#7 ·
I rebuilt the one on my 69 with a kit from Scott Hollenbeck at Muscle Car Research and was quite satisfied with the results. I have no experience with buggered up hydraulic seats so no help there. WCCC does enjoy a good reputation and I would expect they would not sell a faulty used part. I don't know the actual condition of your original part but my first move would be to rebuild it and use the standard steel hydraulic brake lines. Brian
 
#8 ·
Could you please clarify something for me.
Do you have a problem with the distribution block, or the proportion valve?

I have a disc/drum 69 distribution block with bracket I could sell you. I do not have the proportion valve for it though.

You can P.M. me if you would like. I will not be able to respond until late in the evening though.
 
#10 ·
I've used several junkyard proportioning valves. I disassemble and clean them. No issues so far after several years. I also cut all lines to the valve when scavenging valves so that I have the correct fittings for that valve. I re-flare the fittings onto my brake lines as needed. I have to "poor-boy" it sometimes, as I have too many drum brake cars needing conversions.
 
#11 ·
Have you looked at the seat to see what it looks like? Unless you did a really bad job flaring the line then the seat is probably all right. I have seen flares split at the seat and that can cause damage when you tighten it.

I bought a new dist block/proportioning valve for my 69 Mustang 302 from NPD:

https://www.npdlink.com/store/produ..._proportioning_valve_assy_exact-186692-1.html

It works like a champ. I also bought all new SS lines and had no problems with them except where I mated with my non-69 front disc brakes. I had to shorten the lines and re-flaring SS with a cheap flaring tool just doesn't work. Unless you have factory 69 discs or a really highend flaring tool, I don't recommend SS lines. I hope that helps, let me know if you have questions.

david
 
#26 · (Edited)
I went ahead and ordered this one. I didn't have time to dig into the Scott Drake acquisition compared to the timing of the bad reviews, but here's to hoping they have a better machining process that's more leak-resistant. Either way, I feel more confident with that purchase after hearing that some of you are having good luck with yours.

Thanks all for the input. I'll update once everything is in and tested.
 
#13 ·
Great info everyone - I tried to 'quote' multiple people, but that didn't work out so well.

Brian - Thank you for your rebuilding advice. That seems like the most economical route. I still have my new traditional hardlines for MC-to-block that I can use, if needed.

1969sag - I thought the entire unit was called a proportioning valve, but I see where the two come together now. It is my distribution block specifically that is giving me issues. I could likely separate my proportioning valve from the block, but all the lines so far have been frozen on and the nuts could do with being replaced once they are removed. Worried the valve would be no different? I'll let you know if I can take you up on your offer by the end of the week though - Thank you!

Jedi - Good to know! I already had to make some custom hardlines for the MC (back when I thought this would all go back together nicely), so I'll keep those around in case the hardline kit doesn't match up there (likely won't - who decided to change all the fitting sizes on these new MCs?!) :)

Coupster - You're practically my neighbor, no wonder I can't find any good parts in the local junkyards! :)

Moodster - Thank you for the link! Going new could be my best bet. There was definitely a learning curve on my cheap O'Reilly's flare tool. I thought the line would settle down and seat, but I think it scored the brass instead. I can get better pictures of the seat and (for laughs) my flares. I do have factory front disc, which might be my saving grace with these SS lines.

Thank you all for your input. I'm going to check out all the links and suggestions, and I'll report back with what I decide on.
 
G
#15 ·
That's a combination valve. It actually contains several valves and functions. The proportional valve is only used with disc.drum cars, whereas a distribution block is still used with drum/drum cars as well. So if you have a disc drum, then you do indeed have a proportioning valve, but not what you show in the pic. The prop valve can be made as part of the combination valve, or it can be separate from it.
 
#18 ·
Thanks for the link! I'm really happy to see that new ones BESIDES Scott Drake repros are available.

How do you think these are installed? I don't see if they're intended to be used with the factory bracket, an 'under the MC' bracket, or a custom DIY bracket.

Edit: Nevermind, I kept reading and saw the 'related items' part. Durr.
 
#24 ·
The '69 uses an external, in-line proportioning valve, just like the '68. The distribution block contains the differential pressure valve (shuttle) and brake warning switch...that's all. It's possible the seats may be removable by threading in a long self tapping screw and prying up with dikes. Option #2 would be a soft copper seat washer. If the seats, themselves, can't be removed and replaced then the best option would be a replacement, either good used, or a later-style combination valve.
 
#28 ·
I'm a bit confused here, because I can't find the correct 68-69 combi-valve on the CJ's or Drake site, and the photo above of the correct 68-69 valve being referred to as the "Drake repro" is our valve from our website.

If someone can post a link to where the bad-reviews are of the Drake repro, I'd like to see them, to determine if it's actually our valve that's being reviewed.

Long story hopefully short - The only place that reproduced the "correct" 68-69 distribution block & proportioning valve assembly was "Fine Lines" in Wadsworth Ohio. However, over the summer we bought-out all of Fine Lines' inventory (both finished assemblies and bare-components), bought all of the tooling, and now these blocks/valves are only available exclusively from NPD. Drake may have been buying them from Fine Lines, and might still have some inventory remaining, but I can't tell without someone posting a link, because I don't find it on either sites.

We haven't decided yet whether we're going to wholesale these to other suppliers, or just keep them exclusive.

To MrsPib, I have no knowledge of any machining issues with our block & valve assemblies, and assure you that if you have any issues, we'll stand behind it. But you should be in good shape, we sell these things like crazy and they rarely (if ever) come back with problems.

Rick
NPD
 
#30 ·
Good to meet you, Rick. Thanks for reaching out on this thread. It's good to hear a little backstory on these items, and I appreciate the fantastic customer service.

As for the Scott Drake units, I looked them up again and I was slightly incorrect the first time - They are being sold on Summit Racing, Scott Drake #C7ZZ-2B257-A. Description says they are rebuilt 'late model units', and currently have 2-stars and 7 reviews. That makes more sense, that rebuilds are failing more than new parts.

Anyways, again, thanks for chiming in Rick - I think everything should go well from here out, but I'll definitely reach out and speak with you if not.

Have a great week!
 
#29 ·
The combi-valve I purchased from NPD works great. I actually upgraded from a previous valve I had bought from NPD which would have required me switching out my fittings. NPD allowed me to return it even though I had bought it months ago. The only complaints I have about my whole disc upgrade was with the SS lines I bought. I'll list my issues in case Rick wants to consider addressing them with the supplier:

1) The line that runs to the passenger side front disc brake is one piece - all the way across the firewall and through the tower and down underneath the lower a-arm. The factory line was two pieces - one line runs across the firewall then another line runs through the tower - this would have made it much easier to install.
2) The lines have plain steel fittings but there are SS fittings on the market so I'm not sure why they didn't tag on a few bucks and use those.

david
 
#31 ·
Ah, do you know which fittings you had, and which you had to upgrade to? I've had to change out fittings already due to an 'updated' MC that takes over-sized fittings. I was hoping all these manufacturers were talking to each other and coordinating who upgraded to which size, but I'm keeping my already-made custom MC lines handy if not.

That firewall line is going to be a pain. Mine runs from the valve all the way to the outer PS fender wall as well, and I am not looking forward to that install. I didn't know factory was 2-pieces, I guess mine were already changed out by the PO long ago.

I agree, stainless fittings would be great, but I wonder if SS is more likely to chew out your brass threads if over-tightening? I could see that being my luck :)
 
#37 ·
Hey all - Posting a bit of an update.

Got the SS lines, the line adapters, the 3 steel braided lines, the distro/prop valve, the master cylinder, the Midland brake booster, and new calipers installed. Drums, shoes, wheel cylinders, and discs from a previous install still looked good.

The brake system is acting pretty strange now, and I'd like your opinions on what it could be. It's a bit of a developing issue, so I'll list the symptoms in the order that they occurred.

1.) When bleeding the system for the first time after install, the rear bleed normally, the front-passenger side bled normally, but the driver-front side gave one puff of air, then quit getting pressure. We changed out the caliper, thinking it had a stuck piston or bad bleeder

2.) With new calipers, the rear bled fine, the front-passenger bled fine, the driver-front had no fluid, no pressure. We opened up the driver-front hardline at the distro block, and while pumping the brakes, no fluid came out of the distro-block. Meanwhile, with no pressure getting to the front-driver caliper, the passenger-front caliper seized and wouldn't break free.

3.) While leaving the driver-front hardline open at the distro block, we decided to check if the rest of the system was getting pressure at this point (to rule out faulty master cylinder). This is where things get weird, with the front line open (and absolutely no fluid coming out), we pumped up the brakes and went to bleed the rear-passenger drum. As soon as the bleeder screw was opened on the rear, fluid poured out both the rear-passenger and the front-driver lines. I don't understand why this is.

4.) Completely perplexed at this point, we opened up the rear-passenger a couple more times, and as soon as the rear-passenger was open, fluid would come out both it and the front-driver lines. We then re-connected the front-driver side, and proceeded to bleed the system like normal, this time getting a decent amount of pressure and fluid out of the driver-front caliper

However

5.) The 'brake' light will not go out (fluid level good, no leaks at hubs, distro block, wheel cylinders, or master cylinder). I took out the brake switch at the distro block to look inside, and measured the depth to which I can stick a piece of wire down in there. I can stick a piece of wire down further into my previous block than I can the new one, which leads me to believe the moving piston within the distro block has been knocked out of place on the new one. Without an obvious leak, why did it do this? What is a good way for correcting this?

6.) The calipers seem to be sticking. I've had to accelerate through the brakes a couple of times.

7.) The pedal is VERY soft, and returns slowly. I checked for a vacuum leak at the booster (both booster and soft line are new) by disconnecting the vacuum line (engine revs/changes), then reconnecting it (engine calms down/goes back to resting idle). I also felt around booster, soft line, hard line, vacuum junctions, rear of intake and couldn't feel an obvious leak.

8.) During my first test-putt around the block, the car had nearly no brakes. During a test run in the driveway, the car seemed to have more braking power, but still significantly lacking and pedal is soft and slow to return.

9.) Video included, but the car doesn't seem to be braking 'evenly'. In reverse, it bucks quite a bit during braking. The front-passenger side comes up, and the rear-driver side sucks down. When braking forwards, it looks like the front-passenger squats first (slightly), then the front-driver catches up. I'll take it on a test-putt around around the block and update on if it pulls while braking. The previous system did not have a noticeable buck, pull, or any otherwise unbalanced-seeming performance.

So, that's about it in a nutshell. A lot of new parts, so it's possible something either went wrong during install/bleeding, or one of the parts is faulty.

What do you folks think? Any advice or ideas appreciated.

Video of drive-way testing can be seen here: https://youtu.be/H0z4R_VyQcI
 
#38 ·
Update after test-drive:

1.) Brake light was off when I started the car, and stayed off throughout the entire test drive (the light had been on continuously since brake system install, so that's a step in the right direction).

2.) Brake pedal is nearly unresponsive until it's on the floor

3.) Rear-passenger drum is seizing up. Once the pedal is to the floor, and the brakes begin to respond, if you press the pedal just a hair further, you can lock up the passenger drum. I was able to lock it up at just a crawl.

4.) Front-passenger may also be seizing up, but not as noticeably as the rear. Car pulls slightly to the passenger-side when braking. I was able to leave a braking skid mark in the driveway, all the rubber laid down was in the rear, none in the front.

I'm going to try bleeding it again, and see if that helps with the pedal. Otherwise, still trying to figure out why the brakes are favoring the passenger-side, especially the drum (I verified, and the prop valve was installed according to W.C.Classic Cougar, with the part number covered by the bracket and the weep hole at the top).
 
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