KW's 1979 Ford LTD Landau

[Mainemantom]

"Rear counter" parts locator shows two people have that part. You could request a price quote from each seller.

[87gtVIC]

I paid that much ten years ago for one from ford. I am surprised people ain’t asking more now. I was happy to get it back then when I needed it. Of course that is all gone now since I did the big brake swap. Where it is now is anyone’s guess. I know I would not have thrown it out but have kept it for a future build if needed.

[Tiggie]

That seller is pricey. I do wonder if yours can be repaired, or if it blew out whatever plug is back there and is now MIA. I'll be interested to see what's up with it.
I replaced a proportioning valve on a fairly rusty 82 F150 this summer. It came loose without complaint from any fitting. I bet yours comes loose as well. IMO people (me) overtighten brake line fittings and that makes them more of a pain to remove than a factory torqued part.

[kishy]

I'd be ditching that stupid valve (pardon me), as I have on my wagon. Do a 90ish master cylinder and that valve does not exist on those cars, just one continuous brake line to the back of the car. Two outlet ports for the front lines directly on the master itself.

If they'd placed the valve somewhere sensible like under the car (as on my Ranger) I may harbour less ill will for it, but where it is on these cars...absolutely not.

[gadget73]

There should be a shuttle valve in there that moves back and forth to trip the brake warning light if there is a loss of pressure in one circuit. I think the plug is simply the assembly / access hole for machining out the inside of the valve block. The plug should simply be a plug to close it back up again once assembled. If it fell out though I'd have to wonder if any of the inner bits have gone missing or if the threads stripped out somehow.

[Kodachrome Wolf]

I'd be ditching that stupid valve (pardon me), as I have on my wagon. Do a 90ish master cylinder and that valve does not exist on those cars, just one continuous brake line to the back of the car. Two outlet ports for the front lines directly on the master itself.

If they'd placed the valve somewhere sensible like under the car (as on my Ranger) I may harbour less ill will for it, but where it is on these cars...absolutely not.

Oh, I didn’t realize it was that more straightforwards, otherwise I’d have just done that when it needed a MC. That would eliminate a lot of extra work.

Guess I can keep this barely used one for the ‘87.

[kishy]

Oh, I didn’t realize it was that more straightforwards, otherwise I’d have just done that when it needed a MC. That would eliminate a lot of extra work.

Guess I can keep this barely used one for the ‘87.

The one gotcha is that the newer master cylinder (e.g. the variety with a plastic reservoir and the 2 front outlets which doesn't depend on any splitters or valves external to itself) does make use of an inline valve threaded into itself - I believe called a residual pressure valve - which the new/remans usually do not include. So you may be a junkyard trip away from being able to implement this solution.

Some relevant thoughts here: https://www.grandmarq.net/vb/forum/t...18#post1168951
and here: https://www.grandmarq.net/vb/forum/t...18#post1168901

The other gotcha (yeah, I said one, oops) is that if you wish to retain your brake warning lamp - and I'd say that would be wise to do - you'll need to get your hands on the hall effect switch (junkyard again) and make a minor wiring alteration, which I also discussed in #263 linked above. The brake warning lamp's function subtly changes, from "there has been a pressure drop in either the front or rear system" to "there is low fluid in the reservoir".

[Kodachrome Wolf]

The one gotcha is that the newer master cylinder (e.g. the variety with a plastic reservoir and the 2 front outlets which doesn't depend on any splitters or valves external to itself) does make use of an inline valve threaded into itself - I believe called a residual pressure valve - which the new/remans usually do not include. So you may be a junkyard trip away from being able to implement this solution.

Some relevant thoughts here: https://www.grandmarq.net/vb/forum/t...18#post1168951
and here: https://www.grandmarq.net/vb/forum/t...18#post1168901

The other gotcha (yeah, I said one, oops) is that if you wish to retain your brake warning lamp - and I'd say that would be wise to do - you'll need to get your hands on the hall effect switch (junkyard again) and make a minor wiring alteration, which I also discussed in #263 linked above. The brake warning lamp's function subtly changes, from "there has been a pressure drop in either the front or rear system" to "there is low fluid in the reservoir".

I'm familiar with those residual pressure valves, so I've got no issue finding one. FWIW, the brake light never came on when the fronts started losing pressure. Based on a read of your thread and how simple it would be to wire up that switch, I think the late style MC would be the worthwhile swap to get everything working properly again.

[kishy]

I'm familiar with those residual pressure valves, so I've got no issue finding one. FWIW, the brake light never came on when the fronts started losing pressure. Based on a read of your thread and how simple it would be to wire up that switch, I think the late style MC would be the worthwhile swap to get everything working properly again.

Cool, yeah, then I'd say you're good to go on it, whenever you feel like bending up some brake lines.

Do note that the newer masters are metric thread with bubble flare. I keep both 3/8 and M10 flare nuts around for this reason.

I think the benefits of the simplified hydraulic system, reduced points of failure, and ability to see the fluid level without prying off that steel retainer to open the lid do make it worthwhile, if you're otherwise replacing lines or have the system significantly apart. I don't think the newer master is otherwise any better. It does have the benefit of looking a little more modern and since many of them seem to be aluminum, they don't rust.

[gadget73]

whatever you end up doing with it, I want an autopsy report of the failed one.

[Kodachrome Wolf]

whatever you end up doing with it, I want an autopsy report of the failed one.

Well, here's something.


There was a rubber grommet over this end, perhaps a dust cap, but that was it. There are tiny pinholes all the way around the cylinder end of that part of the valve, and it looks like rust and fluid had flowed from those pinholes. I'm not sure how else to "take this apart," but I haven't tossed it yet.

Y'all can stab me later for the very beautiful line unions. Try not to stare too hard down there. Don't worry about all the liquid in the photos, it's just water from knocking any errant brake fluid off surfaces.




I used a retaining valve off a 1994 Crown Victoria for the rear brakes. The rest of the lines were 20" 3/16" line metric bubble flare units that I just cut to size and then made a inverted double flare and mated to line unions. I did find an adapter head for the rear line since that one uses a larger nut. I had one bad inverted flare line nut off the rip, so I had to install another union and redo the line end. Got the system bled out, no leaks. Took it for the spin, and the brakes on this car feel great, arguably even better than before with the old fashion style master.

[sly]

Nice.

[87gtVIC]

Looking real good in there. Unions are fine. Compression fitting on brake lines are not. Gotta do what you gotta do. Nice bends!

[Tiggie]

Haven't seen that fail like that but I now know it's possible.
Looks good to me!

[gadget73]

ok so it didn't have a threaded-in thing. Probably has or had a retaining ring in there to hold it all together. Is that aluminum or steel? If it happens to be a mix of metals, then you get nasty corrosion problems.