Do the 1969-71 Disc Brake Systems use one or two metering blocks?

[EurekaSevven]

I recently assembled all the major components for my disc swap, including the coveted C-Body Bendix booster from a member who was originally going to use it as a spare before I bought it off of him, perfectly rebuilt.
The calipers, rotors, and proportioning valve came from another user, and they look to be in decent shape, but when I was watching a video for the 1972 system (which I believe is the exact same from 69-73), it showed there were TWO prop valves, the one that looked like your normal 'block', and this one, which I do have:

So initially I thought I was still missing a piece, but I decided to check the forms here and the confusion seemed to compound: it seems some factory setups had just the one (that I have), but others used that in conjunction with the smaller, 'block' style metering block, near the driver side frame mount. Is this a critical component, or will mine still work perfectly fine?

 

[luigi164]

See this:

 

[Ross Wooldridge]

There is a small metering block (in addition to the larger proportioning valve) that is placed in the line to the front brakes and is designed to help front wheels to not lock up under braking conditions slower than 5 mph, for example when you are driving in icy conditions.

I have heard that it is essentially useless and that you can eliminate this particular piece from the system and your brakes will function just fine, however, I tend to agree to with TheRamMan and his statements in the video above. If you have it, keep it in place, or upgrade to the combination valve he likes.

Brakes are the most important system on the car. Do it right.

 

[cuda hunter]

Good video.

 

[MrMoparCHP]

My 69 has two blocks. One is a distribution block (not metering) and safety switch. The other is the brake hold-off valve (only on disc brake cars)
Don't confuse the distribution with a combo metering/proportional one like was use in later years (1973).

Distribution block to the rear (left in picture), hold-off valve front (right in picture). The line in the middle of the picture feeds both front brakes.

Alan

 

[Welder guy]

Here are a few pictures of a disc brake setup I liberated from a 69 New Yorker parts car I have , the booster is at Edmonton Brake and Clutch undergoing a rebuild . It’s identical to MrMoparCHP’s setup in his previous pictures. The final 2 pictures are for comparison of a 1971 Plymouth proportioning valve from a second disc brake setup I have . they are quite different in size and setup but end up doing the same job.

 

[EurekaSevven]

I believe that checks out, the calipers and rotors were from a 1972 Plymouth wagon, I believe.

So that Plymouth piece essentially does the two jobs of the upper system, but condensed into a single piece, based on what you said?

 

[Welder guy]

You bet , I can give you detailed pictures of a 69 setup or a 73 setup if needed.

 

[Welder guy]

I just don’t have the brake lines made up

 

[EurekaSevven]

All I would need is the brake lines, since my car is a 1968, I'm not actually sure if I can re-use the front brake lines and the rear line going into the prop valve. Same with the lines from prop valve to MC, since it's originally a drum brake car, and the lines, although rusted, seem to work just fine.

Probably safer to remake the lines anyways, I know they're double-flared and I've seen how to make them (reminds me a bit of flaring HVAC line). It's also a specific diameter of tubing, I can't remember what size right off. 2/32nd?

There's aftermarket lines, but the fitment on those seem to be questionable, as far as bolt-in goes.

Do they make reproductions of the dust seals that goes to the spindle, as a random aside?

 

[Welder guy]

 

[Welder guy]

That seal fits a 73 spindle, your 72 might be a different size , I would check with Napa to be sure that’s where I got my parts from.

 

[EurekaSevven]

That seal fits a 73 spindle, your 72 might be a different size , I would check with Napa to be sure that’s where I got my parts from.

According to another member, for the 69-72 setup, the parts he used were:
Inner Bearings: Tinkem LM 67048.
Inner Oil Seals: 8121-S National
Outer Bearings: Tinkem LM 11949.

Although, when I said "spindle dust seal", I was actually more referring to this part:

 

[EurekaSevven]

Also, the exploded diagram from this FSM also shows two cups that go with the bearings, I don't believe I have those as well, so repros for those would be nice.

 

[71Polara383]

My 69 has two blocks. One is a distribution block (not metering) and safety switch. The other is the brake hold-off valve (only on disc brake cars)
Don't confuse the distribution with a combo metering/proportional one like was use in later years (1973).

Distribution block to the rear (left in picture), hold-off valve front (right in picture). The line in the middle of the picture feeds both front brakes.
View attachment 500075


Alan

Do you have a part number for your distribution block? To the left in the photo.

3420022?

 

[MrMoparCHP]

Do you have a part number for your distribution block? To the left in the photo.

3420022?

That is the number I come up with, no reference to it, I didn't save the box.


Alan

 

[71Polara383]

That is the number I come up with, no reference to it, I didn't save the box.


Alan

I bought a bunch of NOS/random Polara stuff from a guy not too long ago, and one of them was included. Now I know it will work on my 70s with discs.

Thank you.

 

[Welder guy]

This is all I have for pictures of the spindle dust seal , it’s 1/8” thick white foam. Mine is in rough shape but it would be easy enough just to make one. I don’t know if these are reproduced I haven’t seen them for sale.

According to another member, for the 69-72 setup, the parts he used were:
Inner Bearings: Tinkem LM 67048.
Inner Oil Seals: 8121-S National
Outer Bearings: Tinkem LM 11949.

Although, when I said "spindle dust seal", I was actually more referring to this part:
View attachment 500501

 

[Welder guy]

Here’s a close pic of my 69 N/Y distribution block numbers .

 

[saforwardlook]

The small front delay valve was only used in 1969 and 1970. The 1971 - 73 models eliminated it.

The Right Stuff makes the brake lines for our vehicles but they don't always get them right. I had to go around and around with them until they got them right for my 71 models. If you want correct ones for the 1971 models and likely through the 1973 models as well, you should have them duplicate the ones I got from them that were actually finally correct. If you want my order number, they can make those up for you and they will be correct. Just PM me if you want the order number and they will make up a correct set.

The company isn't sure who to believe when making up brake lines since they seem to get different lines from different people. All I know is that I have 10 1971 models and the ones they finally made up for me in the end are correct for every one of my 71s. I bought 11 sets from them so I wouldn't have to go around the merry go round ever again.