Help with old Mallory zb 275

[F-ONE]

Untitled by Travis Brown, on Flickr
Untitled by Travis Brown, on Flickr
Untitled by Travis Brown, on Flickr
Untitled by Travis Brown, on Flickr
Untitled by Travis Brown, on Flickr

I have this Mallory ZB. It's the dual point model with the vacuum brake. As you can see somebody has drilled through the cap for the vacuum brake.

I would really like to get this distributor restored. Since Bubba has retired do any of you know anyone who can repair it and get it back to spec?

If that is not an option, can it be used without the vacuum brake feature? Will work just as a mechanical unit? I can do some basic things to try to get it going.
Any help or advice would be appreciated.
Thanks Travis.

[flathead4rd]

I'm not aware of a vacuum brake on that particular model. I thought that model had mechanical advance.

[F-ONE]

It has both. Mechanical advance and a vacuum brake. My understanding is the vacuum brake is not really "vacuum advance" but it's a "buffer"...so to speak that works with the mechanical advance in this model.

[tubman]

The ones I have seem with a vacuum brake work exactly like the pre-49 Fords. They even use the same leather "brake pad".

[F-ONE]

Thanks tubman. Do you know how this comes off?
Untitled by Travis Brown, on Flickr
It looks like someone has monkeyed with it before.

[tubman]

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I think I have one at my shop; I'll take a look. I know I've had one apart before.

[F-ONE]

Thanks Tubman.

[tubman]

I finally found the original thread I was looking for; sorry it took so long. I have to agree with "flathead4rd" that you do NOT have a distributor with a vacuum brake. I think the boss is cast into the distributor body as a provision for a mechanical tach drive (which isn't there either). Here are the pictures I took of the Mallory for my '51 Olds that does have a vacuum, brake. I think you can see it is completely different from what you have. In my third picture, I think you can see the disc inside the distributor that the piston with the leather pad rides on.

As an aside, this is a very interesting distributor. Not only does it have the vacuum brake, but it also uses a special Mallory "FlashFire" coil that has two primary windings, but only one secondary winding. Each set of points acts independently to alternately energize each of the primary windings that induce an impulse in the common secondary winding. It is a "poor man's" dual coil that doesn't need the expensive specialized cap and rotor most require. In essence, it is like all dual coil distributors in that it is two independent 4 cylinder units, firing alternate cylinders, thus the need for two condensers.

Oh yeah, the last picture is the leather pad that I make for both Ford and Mallory distributors (they use the same one). Note how thick it is.

[tubman]

Crap, I see now that I have one of my older condensers on that distributor. We initially had a lot of problems getting the bottom piece to fit right.

Be assured that problem has now been solved.

[F-ONE]

I have to agree with "flathead4rd" that you do NOT have a distributor with a vacuum brake.

Untitled by Travis Brown, on Flickr

It's threaded right there for what I assumed was a vacuum port. It's really interesting.

[F-ONE]

I got it out. Blowing in that welch plug hole with the advance hole plugged. Air blows out the bottom of the distributor. Pulling a vacuum...air sucks in through the bottom of the distributor. It appears that the vacuum stuff has been removed, if it ever had any.
I guess the best bet is to see if it will work as a mechanical only unit.

[F-ONE]

Originally Posted by tubman

I finally found the original thread I was looking for; sorry it took so long. I have to agree with "flathead4rd" that you do NOT have a distributor with a vacuum brake. I think the boss is cast into the distributor body as a provision for a mechanical tach drive (which isn't there either). Here are the pictures I took of the Mallory for my '51 Olds that does have a vacuum, brake. I think you can see it is completely different from what you have. In my third picture, I think you can see the disc inside the distributor that the piston with the leather pad rides on.

As an aside, this is a very interesting distributor. Not only does it have the vacuum brake, but it also uses a special Mallory "FlashFire" coil that has two primary windings, but only one secondary winding. Each set of points acts independently to alternately energize each of the primary windings that induce an impulse in the common secondary winding. It is a "poor man's" dual coil that doesn't need the expensive specialized cap and rotor most require. In essence, it is like all dual coil distributors in that it is two independent 4 cylinder units, firing alternate cylinders, thus the need for two condensers.

Oh yeah, the last picture is the leather pad that I make for both Ford and Mallory distributors (they use the same one). Note how thick it is.

Thank you so much I appreciate it. Beautiful stuff.