Cooling Problems, where to go next?

[FlatheadTed]

You really need to revers flush it with a water blaster ,hoses of ,Make sure your Vac pipe is in tacked and back out the bolt in the centre of the large nut on the distributor bar two turns ,but it should be timed on a machine

[rotorwrench]

There used to be a radiator shop in most decent sized cities but not so much anymore. An old timey shop would de-solder one of the tanks and rod it out with the proper type rods. They'd solder the tank back on, spriz some black paint on it, and it's be good to go if it passed the leak check. This service is going extinct as time goes by.

[Talkwrench]

Originally Posted by rotorwrench

There used to be a radiator shop in most decent sized cities but not so much anymore. An old timey shop would de-solder one of the tanks and rod it out with the proper type rods. They'd solder the tank back on, spriz some black paint on it, and it's be good to go if it passed the leak check. This service is going extinct as time goes by.

Amen.. There is still a few around here, but as you say going the way of the dinosaur

[LFEngineering]

Sorry for the slow response, been busy with a few customer projects and a family vacation.
Anyway I have an update:

I back flushed the radiator as well as the block, I got some sediment, but no smoking gun.

I also used a borescope to inspect the water pumps, no missing impeller fins or excess buildup. I also stuck the camera in though the lower radiator hose ports, no excessive buildup that I could see. Satisfied with the flow the block and radiator I moved onto the hoses.

Since I was unable to source a proper set of offset hoses for a 37 engine in 36 truck and the ribbed universal hoses almost completely collapse when bending in such a tight area I decided to make my own from 1-3/4 tubing and straight silicone hose. They provide the least amount of restriction given the length / drop of the area.

I took it for a drive Saturday, it was about 85 degrees outside. I drove for just over an hour through varying road and driving conditions (in town, hills, backroad cruising, traffic, you name it). The temperature varied between 125-185 degrees and never overheated. The high temps were recorded after ascending hills (expected). Cruising at 30mph I could get the temp to return to 135ish and stay pretty steady. Coasting downhill at 35-40mph at idle I could even get the temp to drop to <120. Another thing I noticed was a reduction in the foam I was experiencing prior to the lower hose replacement. My theory is the lower hoses were so baldy collapsed / bent they caused excess restriction which lead to negative pressure at the water pumps, the pumps would then draw in air though the seals and foam the coolant/water. This would then increase temps, expand the coolant volume and overflow the non-pressurized radiator.

I still have some driving to do before I call this fixed, but it’s going in a positive direction.
As for the cracked water jacket I’m going to keep an eye on it while I continue to investigate repair methods. It’s not a serious leak, so adding a little water every now and then is not a concern.

Lastly I’m considering upgrading the current 4 blade fan with a slightly larger 6 blade unit.

[LFEngineering]

Pics

[JSeery]

Sponsored Links (Register now to hide all advertisements)

"Lastly I’m considering upgrading the current 4 blade fan with a slightly larger 6 blade unit."

Just be aware a lot of folks do not like the 6 blade fans because of the noise. I'm not sure what your concern is with the posted numbers. If anything it is running way to cool! I would want it to be in the 185 to 195 range.

[tubman]

I'm glad to see you got it figured out, but I agree with "JSeery" about it running too cool. I think that's a much easier problem to solve than running too hot.

[edhd58]

I have learned lot following this.

[Bolts]

In my experience, rubber from inside deteriorating old hoses gets in the radiator tubes. The fact that the bottom hoses were collapsed may indicate such a condition. I suspect your problem all along has been clogging in the radiator. Flushing removes some stuff but rubber in the tubes usually must be rodded out.
I'd watch it carefully and see, but you may need the core cleaned at a shop that can remove it and either rod it out or recore it. I know radiators are expensive, but I would try to stay with a brass radiator if you have to get a new one.
Just my humble opinion. Best of luck with it.

[flatjack9]

You need to get some thermostats in your engine. Running at such low temperatures will do your engine no good.

[donald1950]

in several of my cars with 8BA in an earlier car i found that commercial plumbing houses sell 1 1/4 & 1 1/2 inch 45 and 90 degree solder type bends that fit upper and lower bends. they also have a 1 1/2 to 1 1/4 reducer that is just perfict for an 8BA thermostat housing to 41 pick up radiator addapior. and i use the standard hoses cut to fit. i paint the copper fittings with rustolium satin black. just tape off about 1" of the copper ends or the hoses toll be forever attached to the copper fitting... worked for me.