From SDC Forum

Dec 2011

259 Champ Radiator(s...)

While busting my tail last month, sanding Bondo on the Champ... with it just sitting there not having been run in two months ... suddenly I watched antifreeze running down the drive from two obvious locations in the radiator core.

My first reaction was grab the torch and solder, but after a little thought the question was what other holes had the previous owner plugged with stop leak, eggs or what have you?

Once upon a time I was Controller for Serck Services a large radiator service company so thinking I knew a little bit about the business, I expected to be able to find a replacement or generic that fit the need without the expense of a $500+ re-core. Calls to 4 major radiator suppliers including Serck were met with, "find some one to re-core" or "send us the specs and we'll manufacture one."

Since no one would acknowledge a cross reference table by size, I began the task of one by one searching individual vehicles for a proper fit, left inlet, right outlet, downflow, total width 26", Core width 25", total height 22.5", 2 core etc. 12 hours later I found 1975 Nissan 280Z, an inch shorter core but an extra tube in thickness.

Better yet, I found a supplier with a brass/copper one delivered total price to Denver for $188. As the original budget had $200 for cooling system, with fresh antifreeze this is right on the mark. It even calculates about 30% more capacity! The flanges may require some tweaking, but I look forward to that problem.

Addendum 01 Jan 2012 Beware! The radiator discussion laughinlark refers to says the 280Z will not cool the 259. The one I purchased from "Replacement P634" from Autoparts Warehouse specs the core at 1.88 thick. The "Spectra" 280Z radiator from Autozone however only is speced at 1.063" thick. The current (presumably orignial) core measures 1.25 inches thick. Thus the Autoparts Warehouse radiator should have roughly 30% more cooling capability and the Autozone should have about 25% less!

The only mod that is apparent by specs is the outlet tube size is 1.375 and the Champ is 1.75... Either I'll have to bush it, about the thickness of a hose, or change the outlet.

I will definitely check the core thickness before I install it.... I looked at the aluminum radiator option but like the durability and original appearance of brass/copper as well as the price.

Addendum - July 2013

For the record the Champ is running down right cold with the replacement 280Z radiator. Had it in 15 parades last year and it ran cool in all of them. Had it in another parade yesterday and the temp needle never got above middle… Lazer temp gun showed 30 to 40 degree drop inlet to outlet. As the addendum noted, BE SURE IT IS A 3 CORE WITH ABOUT 2” TOTAL THICKNESS YOU ARE BUYING !!!

The inlet/outlets are smaller but I addressed this buy scouring Advanced Auto’s radiator hose rack to find hoses with one smaller end. Be careful with routing of hoses because they are also closer together.

The radiator in my 63YV are is identical in size to the Champ so should it need a replacement I’ll go 280Z in it too.

I noted that the actual core is exactly the size of the core on my Speedster. I will likely pull the tanks from my Speedster and re-solder the tanks on a 280 Z core.

Incidentally, I did a video of my Champ install process at:

Merlin Klotz