The Stovebolt Site Forums The Parking Lot '60-'66 Trucks How good are these old radiators?

I've had my radiator blow once, but thats cause it had a hole in it. The Hot light came on on my panel and a pulled over and it was just steaming out of it.

But i've always been afraid to go long distances in my truck during the summer. The farthest i go at highway speeds is about 10 minutes at a constant 65 mph. I'm just wondering, how long have you guys pushed your 60's straight sixes?

I have a 63 C20 with a 292, the rear axle is 4.10, Monojet carb leaned out, 10 degrees advance on an HEI, cabover, and 33 inch tires in the rear. I flushed the radiator with the Dupont 2 part flush. Keep it filled with 50/50 anti-freeze, and a shot of rust inhibitor and water pump lube. If I push the engine to 3300 RPM and hold it for 20-30 minutes, I'll start to see the temp gauge start to move above normal. It's never over heated on me, except once when the thermostat stuck.

LG

if the system is clean and you don't have too high a pressure cap, 'these old radiators' are as good as new ones - you could take the rad to a shop and have it checked, but if it hasn't been abused it'll do fine, more likely to have water pump or fan belt problems

I've driven hundred + mile round trips numerous times in my 58, did in the 57 panel I had as well .... I took a 55 International panel I had right across the country 3 times, never any cooling system problems on the road, summer or winter

OTOH, a steady 65 with a 6 and the stock gearing is stressing the engine pretty good, the rad would be the least of yer problems

Bill

Really? I've been 90 with it before! I definitely need to tone it down a couple notches then! I thought cause it only weighs about 2 tons that it was no problem but i guess im wrong!

you must have some friendly rear gears to even get to 90 .... what counts is the rpm, if the engine is screamin it's tryin to tell ya something ... about 2800 steady might be OK, over 3000 for very long is strechin it, and the faster ya go the more heat will be generated everywhere, including the wheel bearings

Bill

you are "afraid" to go long distances, but took your truck up to 90 mph???

Well i know i dont have no 4.11, and my bets on a 3.73, but the lowest rear end for my truck was only 3.03 or something like that. I have my tailpipe cut off right under my cab, but unless i goose it completely, it doesnt scream over 70. But I know you guys know better than I do, so I'll try to be good to my Orange Outlaw.

I used to run 65-75 in my 56 235 3spd and I think 3.90s b4 I had to park her during a divorce. Sat in a field 5 years cleaned up points and she started. The days I drove it to work it was 44 miles 1 way across Dallas Tx.
Point is treat them right and the old iron can be as dependable as the new stuff.

Brad

Ps To this day the radaitor tank is stamped 1956. I bought it in Oct 1980 and never had to recore yet.

My '62 Suburban is my daily driver. The '60-'62 radiators are different than the '63-'66.
What I found is that the original radiators on '60-62 used a bigger 3/4-ton radiator for automatic transmission applications. It's slightly bigger, and slightly wider, and is a bolt-in. I got a repro 4-core, 3/4-ton radiator from US radiator.

I also hunted for a factory fan shroud. It took a lot of time, but I found one. The '60-'62 1/2-ton radiators used a different style than the 3/4-ton, so I've had to find all three styles before getting the right one. It isn't on yet though.

My truck was a 283, and originally came with a HD 7-blade fan. I replaced it with a 7-blade clutch fan. It sits back from the radiator 6 inches (which is a LONG way), and still will hold a piece of notebook paper tight to the radiator at idle. I expect it will suck small birds out of the air once I get the shroud on.

I also used a 160-degree thermostat in the summer, as it pops open sooner and I think that gives me a head-start on keeping things cool. In the winter, it runs too cold, so I use a 180-degree.

I've replaced the 283 with a 290hp crate 350, 4spd OD manual trans and 3.42 gears in the rear. I drive in Atlanta traffic with little problem (the shroud will all but eliminate what little concerns I do run into), and honk down the experessway in the left lane, passing people like they're standing still.

I've driven it to Maxton, NC, West Palm Florida (1,600 mile round trip), Ocala Fl (1,000 mile round trip), and I'm heading to Joplin, MO next week (2,000 mile round trip).

As I said, the radiators are different between the years, but you should be able to get a bigger radiator, a clutch fan and a fan shroud without any problem.

-Brad