Thread: 64 C10 w/350 running hot

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I have tried about everything, from running a gutted thermostat, to running no thermostat, even added an electric fan, and the super expensive super-cool anti freeze. Pump, radiator, hoses are all new, and engine was recently rebuilt. ( well about four years ago, but it only gets about 1K p/yr ) Dam thing has run hot since it was dropped in. not a problem in the winter, ( 185-190 ) but once the weather gets over 70 degrees, it runs 220, and gets there fast. I am convinced the three-core radiator just ain't gonna get it. ( and also, I recently threw a belt and the belt pushed a blade into the radiator, and it is toast )

LONG STORY SHORT... Who makes a four-core radiator whch will fit my 64 C10 with little or no modifications, and will COOL a 350 in 90 degree Georgia summers?

Thanks

are you sure its running 220? does it overheat?

it is not uncommon for gauges to run +/- 10%!! So 220 could possibly be less than 200!
Try a different gauge to verify...
Is the temp sensor in the head or the intake...
If it is in the head, are you running headers? this also can give an incorrect high reading!

I am assuming the water and steam boiling out of the overflow confirms the guage reading.

Have you tried a new radiator cap? If it's bad it will not maintain pressure which will cause overheating.
What kind of shroud do you have? If any? A good shroud with a good clutch fan is the probably the way to go...
Mark

Originally Posted by astroracer

Have you tried a new radiator cap? If it's bad it will not maintain pressure which will cause overheating.
What kind of shroud do you have? If any? A good shroud with a good clutch fan is the probably the way to go...
Mark

If its boiling out at 220, then you are not maintaining pressure....

Do you have a shroud on it? How about the filler panel from the top of the rad to the grille support? Without that piece, hot air recirculates over top of the rad and back through it. I've seen big blocks in those old trucks with stock, 283 rads with no cooling problems.
Is the truck slammed? Sometimes if they're really low the air can't get out of the boiler room.
If you need a new rad anyway, get the biggest one that'll fit. A GM diesel pickup rad will cool it, if it'll go in there.

if your cap is good get another radiator. buy one of those generic fit radiators from mail order. they are fairly cheap.

The radiator was new, three core. I was running a stock 77 firebird fan on a clutch. The electric fan sits in front of the radiator and pushes through, the mechanical behind and pulls. Pretty sure the cap is good, as if I try to remove it when it is hot I get a serious blast of steam for the effort. There is no shroud, but does it really make a shit of a difference when the dam radiator is sandwiched between two large fans? Also, it will reach 200+ within a MILE. I am almost wondering if there is blockage in the block passages.

I just knew this engine would be trouble. It came from the 'chicken bone'. The chicken bone was a 70 something chevy truck which, when I bought it, was full of churches chicken boxes ( and bones ). The motor was originally built to go in a SWEET 76 Z camaro, but I ditched the project. Didn't trust the motor to sell it untested, and my intuition was on the money. Turns out, somehow ( just how does this happen? ) the fuel pump pushrod bore got scored up. Wouldn't be a problem until the block got hot, then it would loose fuel. I probably would have figured that one out sooner, but at the same time it had an intermittent ignition problem: The pick up coil on the HEI had lost its locator tit. It would rock back and forth, and this had caused the wires to crack. They would occasionally ground out, causing a miss. Trying to trouble shoot these problems simutaneously was a real bitch, I'll tell ya. Anyway.. the curse of the chicken bones remains.

I really think I need a bigger radiator. Just need a supplier.

First thing I'd do is get rid of the clutched fan and find a six-blade truck fan. Flush the system with lots of volume of water, a garden hose isn't enough. Other things that make 'em heat are retarded timing and lean mixtures, but I imagine you already checked that.
Not really clear by your posts if you rebuilt it or got it rebuilt,or how it ran in the chicken truck. Could it be the head gaskets backwards or corroded through, so the water is only circulating through the front of the engine? That can happen if it had straight water, and steel gaskets. Heating that fast, and lots of steam at the cap, would lead me to think there's compression getting into the cooling system.
Just a few things to think about before investing in a rad that may not cure the problem.

the clutch fan is in the trash, it got fubbered pretty good. The engine was fully built before it was dropped in, but I dont' remember did I bore it over or just hone it? Dam thing been running hot since it came to life. I had seriously considered a blown head gasket, but it runs too dam good for that. Besides, I would be burning coolant, wouldn't I? the timing IS retarded a touch, as it has a fairly hot cam, and I found that cutting the advance down a bit saved me about five degrees. But I am loosing power because of it. As for the carb jetting, it is actually running a bit rich. I was thinking to do a compression check, that would confirm the head gaskets yes?