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Bad proportioning valve?

Rck68

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hi All,

I just redid my front brakes to disk with ‘the right stuff’ kit on the 68 charger, installed new brake lines too.

When I’m bleeding the brakes I get nothing coming out of my rear brakes at all, then a crap ton of pressure bleeding only from my passenger front side. Nothing comes from driver side front either.

Is my proportioning valve bad? What do you think? Thanks in advance!
 
Before you go to the trouble of removing the proportioning valve, try disconnecting the steel line from the rubber hose on the lines your not getting fluid from. If you have fluid there you'll know what is wrong.
 
Before you go to the trouble of removing the proportioning valve, try disconnecting the steel line from the rubber hose on the lines your not getting fluid from. If you have fluid there you'll know what is wrong.
Ok yeah great idea, I should have done that when I was down there. I’ll check tmrw
 
I had the same issue on my 68 Charger when I installed new brakes. I couldn't get any fluid to the rear brakes. For some reason, it seems everyone has trouble with the proportioning valves from Inline Tube. Not sure why but I tried two of their valves and neither one worked. They sent me a new one with no questions asked so it was not the first time they had heard about it. I still have both of them. I got one from Cass at Dr Diff and finally got one that I could bleed properly. I had trouble with that one also but it was a shorted switch for the brake light staying lit up. I don't know why they are so much trouble but you are one of many. Not only Mopar people either. Good luck finding one that works!
 
hi All,

I just redid my front brakes to disk with ‘the right stuff’ kit on the 68 charger, installed new brake lines too.

When I’m bleeding the brakes I get nothing coming out of my rear brakes at all, then a crap ton of pressure bleeding only from my passenger front side. Nothing comes from driver side front either.

Is my proportioning valve bad? What do you think? Thanks in advance!


I don’t know , but if you have installed the combination valve VL-3360 I think you have to screw out the warning light adapter and screw in a Plastik tool for bleeding probably you’re brakes

24D2E2FD-379B-4F6D-8231-D890A3E46ED2.png
 
This*** I was going to say it probably needs to be "centered" till pressure on both sides
Yes I do have the original combination valve, I did not change that out.

It did work prior so that’s why I kept it, and now questioning maybe I’m doing something wrong.

I did not know you have to take out the light adapter thing (not even sure what that was for really, I have the wire that goes on it though).

What is this this tool I have to plug in instead into the adapter port hole? Honestly I don’t think there should be anything wrong with the proportioning valve, as it did work before.
 
Here is a tip, get someone to try and pump up the brakes and break open each connection one at a time just enough to get some fluid to seep out (need to probably pump for each attempt) but this will tell you quickly where fluid is and isn't.
 
I had the same issue on my 68 Charger when I installed new brakes. I couldn't get any fluid to the rear brakes. For some reason, it seems everyone has trouble with the proportioning valves from Inline Tube. Not sure why but I tried two of their valves and neither one worked. They sent me a new one with no questions asked so it was not the first time they had heard about it. I still have both of them. I got one from Cass at Dr Diff and finally got one that I could bleed properly. I had trouble with that one also but it was a shorted switch for the brake light staying lit up. I don't know why they are so much trouble but you are one of many. Not only Mopar people either. Good luck finding one that works!
@Sixpactogo The dr diff valve is like the original one I have rn. You say you didn’t have to remove any piece of it to bleed? I might just grab a new one
 
Yes I do have the original combination valve, I did not change that out.

It did work prior so that’s why I kept it, and now questioning maybe I’m doing something wrong.

I did not know you have to take out the light adapter thing (not even sure what that was for really, I have the wire that goes on it though).

What is this this tool I have to plug in instead into the adapter port hole? Honestly I don’t think there should be anything wrong with the proportioning valve, as it did work before.
Alot of them do have a button that has to be pushed. On yours,Im not sure if it's under the switch. I'd wait till someone who knows for sure replies.
 
I had the same issue on my 68 Charger when I installed new brakes. I couldn't get any fluid to the rear brakes. For some reason, it seems everyone has trouble with the proportioning valves from Inline Tube. Not sure why but I tried two of their valves and neither one worked. They sent me a new one with no questions asked so it was not the first time they had heard about it. I still have both of them. I got one from Cass at Dr Diff and finally got one that I could bleed properly. I had trouble with that one also but it was a shorted switch for the brake light staying lit up. I don't know why they are so much trouble but you are one of many. Not only Mopar people either. Good luck finding one that works!
Also, do you guys have a metering block for your front brakes attached to your combination block? Or just combination block alone?
 
Yes I do have the original combination valve, I did not change that out.

It did work prior so that’s why I kept it, and now questioning maybe I’m doing something wrong.

I did not know you have to take out the light adapter thing (not even sure what that was for really, I have the wire that goes on it though).

What is this this tool I have to plug in instead into the adapter port hole? Honestly I don’t think there should be anything wrong with the proportioning valve, as it did work before.
If you had drum brakes and converted to front discs, you cannot use your original metering block. You need to upgrade to a Disc / Drum proportioning valve. As for the light adapter thing you mentioned..........It is a merely a safety thing. It sends a signal to your brake light on the dash if it sees an unequal pressure problem between your front and rear brakes. That is its only but important job. Call Cass at Dr Diff. and tell him what you are working on. He will get you the correct proportioning valve. He told me he gets his from a different source than Inline Tube. The one I got from him worked except the switch for the brake light had a partial short and turned my brake light on real dim. I replaced it with my original switch from my metering block and have not had problems since. It seems like those brass valves are troublesome since I have had conversations with a couple Chevy guys that have had issues with them as well. Like I said, Good luck finding one that works.
 
If you had drum brakes and converted to front discs, you cannot use your original metering block. You need to upgrade to a Disc / Drum proportioning valve. As for the light adapter thing you mentioned..........It is a merely a safety thing. It sends a signal to your brake light on the dash if it sees an unequal pressure problem between your front and rear brakes. That is its only but important job. Call Cass at Dr Diff. and tell him what you are working on. He will get you the correct proportioning valve. He told me he gets his from a different source than Inline Tube. The one I got from him worked except the switch for the brake light had a partial short and turned my brake light on real dim. I replaced it with my original switch from my metering block and have not had problems since. It seems like those brass valves are troublesome since I have had conversations with a couple Chevy guys that have had issues with them as well. Like I said, Good luck finding one that works.
Thanks for the response. I had disc/drum before as well. But I’ll look call dr diff and make sure. Also, I finally figured out how to bleed brakes through the proportioning valve and why so many have problems with rear, and wit unequal pressures. Nobody talks about the PV brake bleed tool!!

This is what everyone needs and should be included in all brake kits imo. Fits into where the switch fits to keep the piston inside the proportioning valve from moving, during the bleeding.

E6B2A0D1-F04C-4CFE-AB06-2708D418C38E.png
 
Thanks for the response. I had disc/drum before as well. But I’ll look call dr diff and make sure. Also, I finally figured out how to bleed brakes through the proportioning valve and why so many have problems with rear, and wit unequal pressures. Nobody talks about the PV brake bleed tool!!

This is what everyone needs and should be included in all brake kits imo. Fits into where the switch fits to keep the piston inside the proportioning valve from moving, during the bleeding.

View attachment 935132
Never seen one of those before. Where are you guys buying them, and doesn't fluid leak out of the port when you remove the tool?
 
Never seen one of those before. Where are you guys buying them, and doesn't fluid leak out of the port when you remove the tool?
There is no fluid coming out from where the switch inserts normally. The piston inside has rubber o ring seals on either end.
Can buy on summitracing or eBay. Called proportioning valve bleeder tool or pv tool.
 
There is no fluid coming out from where the switch inserts normally. The piston inside has rubber o ring seals on either end.
Can buy on summitracing or eBay. Called proportioning valve bleeder tool or pv tool.
So you just screw it in and do your normal bleeding? And that will allow more fluid to get to the rears?
 
So you just screw it in and do your normal bleeding? And that will allow more fluid to get to the rears?
Yes apparently this is what most get wrong, that they pump the brakes, hold it down, meanwhile shunting fluid only to the front and wonder why it’s not going to the back.

The pv tool will center the piston, so fluid can reach everywhere during bleeding.
 
I've been looking for one of these centering tools, but none of the options I've found fit mopar, only GM. Some have said they use a screwdriver to keep the shuttle valve centered, but that seems it would not stay secure.

Anyone find a source for one of these PV threaded tools that will fit my mopar distribution block brake switch port?
 
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