Aluminum Radiator Restoration

Assuming you have the original stacked plate radiator, there isn't much that can be restored. Repairing leaks should be done with an epoxy, make no attempt to weld, braze or solder. The core cannot be replaced, as the tank is integral to the core. All you can do is chemically flush it, which can be done by any radiator shop.

As for cosmetics, it's difficult. Highly alkali strippers will damage the aluminum, so you will need to find a solvent that will lift the paint. the fins can be straightened to a degree, but bear in mind that the brazing runs through the middle of the fin, so if you do to much metal work, you can compromise the radiator.

Once the paint is removed, you can use a semi-gloss black enamel, without priming. Bear in mind that only the top, bottom, and "tanks" were painted, the center "core" of the radiator remained bare aluminum. I know of no safe way to restore the original patina of the aluminum fins.

Stacked plate radiators are very strong, and were probably adopted from aircraft coolers. These radiators had more radiating surface and were lighter than the brass version that followed, and the construction is unique. They were constructed by literally stacking the stamped plates face to face, with an intervening "gasket" of brazing material. The entire radiator, assembled in a jig, was then dipped in a hot salt bath, which melted the brazing compound and sealed the assembly.

The Marston tag is being reproduced, if yours is in poor shape. The unique stamps used by Marston are not, however.

The only other car that I am aware of that used stacked plate radiators was Corvette.While the Corvette radiators are being reproduced, the low volume production of the Jaguar radiators makes a true stacked plate copy cost prohibitive. There are modern versions using aluminum cores welded to machined tanks that have a very similar appearance to the original, but nothing that is a letter-perfect copy. If you can keep yours going for a while, do so.