VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 38 Over Heating

Just as an update, I had overheating problems on my 38 with original 216 engine and tried everything to get it fixed; changed thermostats, took out the thermostat, flushed the engine, added wetting agent to fluid, changed the coolant, changed the fan blades, changed the water pump, etc., etc..

As a last resort I bought a used radiator, had it re-cored and finally got around to swapping it in last night. I ran the car for over an hour with no problems so I think this solution solved the problem. So if you are struggling with overheating problems, although this definitely was not the cheapest or easiest solution, it did work.

Brian

Brian,
Thanks for the up-date. I have seen more than one example where replacing the core was the only solution and have the old core "cleaned" was of no help.

What a PITA. I'm happy you got it figured out.

Glad you found the solution.

Actually the radiator core only needs replacing when it experiences one of the following (I'm ignoring the stop-gap solution of reverse flushing):

A. It Is rotten so badly that it cannot be rodded without creating too many major holes in the flues.

b. Too many flues cannot be successfully rodded to the extent that there are insufficient flues left to successfully cool the engine. More than about a quarter percent of them.

c. The core is damaged from a wreck or something and too many flues have to be cut out and solder up at their ends or at the tank(s).

Otherwise, a radiator core can be successfully boiled and rodded and any holes under test soldered up. When done right, it will perform as intended.

I've done a heap of them and my father before me did a whole heap(read many, many more) before me. I did the rodding for him for many years back in the forties and the fifties as well took the radiators out and reinstalled them.

I don't know if that service can still be had or not. I think such radiator shops may still exist but not as many as in times past.

When needed, we used Harrison and McCord radiator cores, depending on the make of the vehicle, etc.

Charlie

I've always found "wetting agents" to be worthless...In general, if it's not the thermostat, you gotta get another radiator...Don't risk the damage overheating can cause...You'll be sorry you didn't just "bite the bullet" and invest in a new radiator, don't risk wrecking the motor, i.e. cracked head ...I don't know of any shops that will tell you "rodding out" will be of any help, anymore...Of course, they want your cash...Plus, they want it done right, anyways...I've had some luck flushing with Miratic acid, but it's still a 50/50 proposition...

New is better

A lot cheaper than rebuilding an engine...I see the temp. above what it should be, I pull over and pop the hood 'till it cools down...And I never add water to a hot motor...

I fought this problem for years with my 37 MD with little success until running across a catalog from Walker Radiator Works and found a fan shroud that fit my radiator. A larger fan and some minor fabricating seems to have made a huge improvement in air flow. A 90 mile test drive on a hot day with the temp never about 190!

I thought about that because when I did a spot test of the operating temperature, using a laser thermometer at various points along the radiator, there was significant variation in the temperature. One of my concerns though was that the engine would boil over after it was driven for a short time. As soon as the engine stopped the temp would rise and within a few seconds, boil over. That made me think that maybe there was a pocket of hot metal somewhere in the engine that was not detected by the thermostat. If that was the case, then maybe blockage in the radiator was contributing to the bad flow (I had swapped out everything else) that was allowing the hot spot. If that were true then a shroud would not remove the hot spot.
Plus the car didn't need one when it was new and in theory I was supposed to have just finished restoring the car to like new, at least that was the theory.

Brian

When we had the shop we replaced or recorded a lot of radiators because the fins were bad and would not transfer the heat. They have to flow good but the heat has to be able to get away from the tubes.