Technical Mallory distributor part number list

bttt

 

I wonder how many of those part numbers were actually represented by a physical example.

 

Hey guys, I have recently acquired some Cadillac 331 stuff, in which a Mallory Magspark distributor and transformer were included.
So looking at the tag, it is model ZCM, which seems to mean that it has both centrifugal and vacuum advance, 24875-b circuit breakers, and is designed for use with the Magspark transformer. All good there. But, the type stamping has me a little confused. It is stamped 248 AB, which is indeed the type for a '49-'51 cadillac, but the AB has been restamped, with a deeper AX over it. What would that mean?
It also appears that possibly the M on the model designation could have been stamped at the same time as the AX.
Also, and I see the Magspark is a dual spark, I would assume that im missing a set of points inside the distributor. Is this going to be a hard item to replace? And the last question, I have just gotten it and have not dug into it at all, but the rotor will only turn about a half an inch and it hits something to prevent it from turning any more. Obviously, I have to open it up, but any ideas on why that might be? Maybe there is something common with these?

Here are a couple photos.

 

You need an additional set of Mallory 24875 points and if you do use the MagSpark transformer the point sets are not connected to each other, they are wired independently to the MagSpark transformer.
You did not mention your distributor cap but I suspect it is the later Mallory 4004 black cap. Your rotor is the Mallory 24215, it has a spring under the contact and the contact is longer interfering with the contacts in the 4004 cap. A Mallory 4215 rotor will be compatible with your black distributor cap and be much cheaper than paying for a good brown 24004 cap.

 

Awesome. Thank you guys.
Fordors, it has a brown 24004 cap in fantastic shape. The issue with it not spinning, is still an issue with the cap off.
The number on my points plate is 24878, and you are correct on the rotor, it is 24215

 

My guess is that Mallory had an "-AB" distributor in stock and got an order for an "-AX" unit. So they just recurved it and restamped it before sending it out.
The restamped "M" is over an existing "M", maybe they just wanted it more bold.

 

Hey thanks for this, going to come in really handy

 

Thanks Mark. This thread has been very helpful to me.

(There is a remarkable amount of Mallory stuff still out there in some strange places.)

 

Great info! I missed this the first few times it came up. Coincidentally, I finally found a source for the vac advance dash pot that was bad on the Mallory for the 390 in my OT ‘68 F250. She runs like a champ now!

 

& that source is??? An interchange?
Marcus...

 

Finally found this guy through some truck forums. He has all the old Mallory dash pots. Called him up and $65 and 3 days later I had one in the mailbox. bob@system1filters.com

 

Thanks.