71 combo valve

[Heirloom]

Hi all. I am having to install aftermarket SS brake lines since my flaring tool is making bad flares. The closest thing I could find were lines for a 71. They are different because the 68 lines had a splitter block mounted on the engine cradle that split a single line into two for the front. In other words there is one line out to the front from the proportioning valve to the splitter. The new 71 lines seem to all go straight to the prop valve location. So my question is this...

Does the 71 combo valve have 2 in and 3 out (1 rear, 2 front). If so where's a good place to get a new prop valve that fits where the lines go? Or maybe someone has the right valve in a box and would sell it to me???

I'm really running out of time here....calling all FORDification friends. Thanks!!!


EDIT....OR, can I simply get an adapter fitting to screw in the to the top, capped port on my existing prop valve? My original valve has enough ports, and in the right location. But the one top port (where the passenger front line would connect) is plugged and not the right size thread (valve port is larger diameter/thread than the line fitting). Thoughts??

[ultraranger]

A photo of the actual valve, you currently have, would be helpful in giving you the most accurate response.

[Heirloom]

Sorry for the crude paint brush writing. This is the main prop valve on the drivers frame rail. The top port that was capped is open to the front circuit. With a 1/8npt to 3/8-24 inverted flare fitting my new line will go right in.

[Heirloom]

Sorry, not a prop valve. It's just a distribution block and warning switch housing.

[ultraranger]

Do you have drum brakes in the front or discs?

[ultraranger]

I looked at your project thread and see that you have discs on the front. Discs were optionally available beginning on the '68 F250 and F350 trucks but, were not standard.

Did you add the front discs? The brake valve you have suggests the truck originally had all wheel drums, since that valve is a pressure differential brake valve designed for all-wheel drums --not the correct valve style for discs front/drums rear.

--although, I don't know that I've ever seen a factory brake valve for a pre-'73 model truck with discs front/drums rear.

Prior to 1970, any Mustang that came with factory front discs had a brake valve that looks similar to the one you have but, it had an additional set of ports on the front of the valve body with an external proportioning valve plumbed into it.



In 1970, the Mustang disc/drum brake valve combined all the valve functions (pressure differential sensing and proportioning) into one valve body.



I'm uncertain when the disc/drum brake valves for the trucks combined the various functions into one valve body but, I know by '73 this had happened.

The trucks disc/drum combination valves have an additional feature the Early Mustang valves don't have. In addition to pressure differential sensing and proportioning, the disc/drum truck combination valve body contains a metering (hold-off) valve for the front (disc) brake circuit.

There are two different disc/drum combination valves from the '73-'79 Dentside trucks that I'm aware of.

One is a cast iron valve assembly that was made by Kelsey-Hayes. (This one I pulled from a '77 F-100).



The other disc/drum combination brake valve has a brass valve body and was made by Weatherhead. (I pulled this one from a '75 F-350).




I recently swapped the stock front drums, on my '69 F-100, for discs from a '77 F-100. This is the factory drum/drum pressure differential brake valve I removed.



I replaced the drum/drum pressure differential valve for a disc/drum combination valve. It's an NOS Ford/Weatherhead valve I got off ebay ($124.00).

[Heirloom]

Wow, thanks for the info Steve. It seems this truck was rocking disc brakes (on it when I bought the truck) and the original drum/drum valve. I find it interesting that the kit I bought from inline tube (spec'd for a 71 disc/drum longbed) has lines that match up to this valve, mounted in the factory spot on the frame, perfectly. No way it fits any other setup.

[ultraranger]

Wow, thanks for the info Steve. It seems this truck was rocking disc brakes (on it when I bought the truck) and the original drum/drum valve. I find it interesting that the kit I bought from inline tube (spec'd for a 71 disc/drum longbed) has lines that match up to this valve, mounted in the factory spot on the frame, perfectly. No way it fits any other setup.

Was that valve the only brake component plumbed into the system? --no factory external/inline proportioning valve in the system?

The '67 Mustangs that had factory front disc brakes had a Kelsey-Hayes proportioning valve valve that was plumbed inline to the rear brake circuit. The proportioning valve on them was located near the rear axle housing (this exact same proportioning valve was also used on the '65-'68 Corvettes).

[ultraranger]

After taking a look at this diagram, I see that the '68-'72 F-250/350 trucks, with factory disc brakes, had a pressure differential valve (# 2B257 in diagram) like a truck with all wheel drums.

http://www.fordification.com/tech/image ... system.jpg

However, I also see in the diagram a factory disc brake '68-'72 truck had an external metering (hold-off) valve. I can't tell if it's mounted on the left frame rail or on the back of the cross member but, the metering valve is # 2B161 in the diagram.

I don't see any proportioning valves in the diagram.

I guess by '73 Ford knew a lot more about disc/drum brake systems and decided to add the proportioning valve (inside the combination valve) of the '73 - up model trucks.

[Heirloom]

I have 2B257 and 2B161. Using this brake line kit would eliminate 2B161 and run the same as the drum drawing does, with the front wheel lines going directly to the 2B257 pressure diff. valve.

I have contacted In Line Tube.