A tale of two radiators
When Dad got the truck, it didn't have the original radiator in it. Somewhere in it's history, someone decided to hack in a 60's vintage Mopar radiator from an old slant six rather than install the proper radiator. As you can see in the feature photo, that's the Mopar radiator along with a hacked up radiator frame to accommodate the non-Harrison radiator. Thankfully Dad was on the road to rectifying this; his spare parts I have for the truck included a factory Harrison radiator and frame....Great! I needed to do the radiator anyway, as when I got the truck running there were a few small leaks around the top tank once I got it up to temp.
I took the old Harrison radiator to a local shop to have it looked over. Unfortuately, when they hooked it up....there were 20- 30 leaks in the core, and having them re-cored is a VERY expensive proposition, as these are copper core radiators. Thankfully there are options for radiators on these trucks...you can get a modern aluminum radiator...all the retro parts shops have them and it turns out you can even get one on Amazon. I went with this option.
The old frame was rusty, but nothing some quality time with a Dremel and wire brush attachments couldn't handle. I got it cleaned up and re-painted it flat black just for rust prevention. I pulled the old Mopar radiator and frame out and installed the proper factory frame in the truck. All that was left was to drop the new one in....or so I thought.
I had to get some new hardware to mount the radiator to the frame...it's all standard stuff, 5/16th bolts with 18 thread pitch....a few trips to Lowe's and O'Reilly and we're ready to bolt it up. I did have to trim the frame slightly with a Dremel (did I mention this is fast becoming the most valuable tool in the shop?) to get the newer aluminum radiator to fit right in the 70+ year old frame, but it wasn't terrible. All bolted in and now ready to reassemble the rest......
HOUSTON WE HAVE A PROBLEM
No way there is enough clearance for the fan! In fact, I didn't even have enough room to put it back on. Now I'm pissed! God Damn Chinese mis-engineered parts (or so I thought initially)! After I put my tools away and cleaned up a bit - because there is no way I'm continuing now and I'm angry enough to really mess something up on the brakes - I decided to knock off for the day. I head to my office to do some research on a different radiator. Perhaps I can find a Harrison on eBay.
WELL.....it turns out, after some perusal of the forums on https:/www.stovebolt.com, the radiator itself isn't the issue. Dad's truck has a 55-57 Chevy 235, I had verified this some time ago by looking up the casting numbers on the block. This is a common mod for these trucks, as in the mid 50s the same basic engine was upgraded with niceties like hydraulic lifters, higher oil pressure, etc. A mid 50's stovebolt is ALMOST the same engine, but there are little differences. One of those differences is that it is slightly longer. DOH! Now I know why Dad's truck had this hack-y Mopar radiator....the factory Harrison radiator doesn't work with a 55-57 stovebolt.
What to Do?
At first I thought I'd have to put the hack-y radiator frame back in and start looking for a compatible slant six radiator, but it turns out I don't have to do that. Luckily the Truck Shop in Concord sells a lower profile water pump for this exact situation.
Unfortunately the Truck Shop is closed on Sundays and Mondays so I will have to wait until Tuesday to get one and in the mean time pray to the parts gods that it's in stock. The Truck Shop is about as old school as you can get. There are no computers and no e-commerce. Everything they do is by hand.
UPDATE: Part 2 and the conclusion.