radiator troubles

[blizzardwarrior7]

So my new to me 1954 GMC has been home now for 2 weeks or so. Water pump and radiator replaced. Still having trouble with the radiator. I can idle the truck for about 5 minutes to warm up, and than within 3 minutes of driving it overheats the temp guage shows just under 220 and I have steam pouring out of the overflow along with some coolant. Does this sound like a clogged radiator? Also started stripping paint and sanding so will have new pics of that up once it stops raining.

 

[73m819]

could be a head gasket/ cracked head, if it got hot from the bad water pump or rad. it very well could be

 

[bones1]

This is a M211 gas 6cyl I suppose?.
What is still wrong with the radiator after being replaced?.If the radiator is new you must look elsewhere. Thermostat may be stuck shut(likely) or worse the head gasket may be blown between cyls.

 

[blizzardwarrior7]

But wouldn't a bad head gasket mean the engine would be burning coolant while it was running? I the coolant level is staying the same unless it starts leaking out the overflow. Also the radiator initially went out because the water pump bearing went out, causing the fan to strike the radiator and cracking it. It now has a new water pump and radiator. Is there any way of ruling out the headgasket? The radiator is getting hot, didn't check the top hose good idea, is a stuck thermostat common on these engines?
Also I mispoke, the radiator is a takeoff radiator that was supposedly pressure tested by tom at alpha.

 

[Squirt-Truck]

To check for stuck thermostat, let it warm up and check the top hose, if it is not HOT then thermostat is stuck. IF the hose is hot, feel the face of the radiator, if it is cool from top to bottom radiator is clogged. (New radiator not likely.)

Let us know.

 

[bones1]

Look for a stream of bubbles in the radiator while it is warm and running.I suspect a crack/ gasket as well,BUT check the thermostat if it has one?.

 

[bones1]

10-4 Squirt

 

[blizzardwarrior7]

I didn't see any signs of bubbles at the radiator cap, or any water in the oil, or see any smoke at the stack, wouldn't a headgasket display at least one of these symptoms?

 

[bones1]

Yes it would. You would have white smoke(vapor) if you were burning water. Have you done the top hose/ thermostat check yet?.

 

[73m819]

If the thermostat, pump, rad.,are GOOD, has to be a crack that allows exhaust gasses to enter the cooling system

 

[bones1]

Eliminate the above easy stuff first than pull some spark plugs and see if you are burning water.
Remove the dipstick and let a drop of fluid fall on a hot part of the engine - oil will smoke water will "sizzle
Check your oil for milky color.

 

[blizzardwarrior7]

I m going to try a few more of the suggested tests tommorow, and will post my findings, still hoping its a clogged radiator or something simple like a thermostat. Thanks again.

 

[armytruck63]

If the thermostat, pump, rad.,are GOOD, has to be a crack that allows exhaust gasses to enter the cooling system

This is exactly how I found out that my M38A1 had a cracked block.

A welder friend brazed up the crack and he put a helicoil in where the crack was near a head bolt thread. It's been four years and everything seems to be holding up.

 

[blizzardwarrior7]

Thermostat was sticking a bit, so removed that and replaced it. Truck is running for about 15 minutes at a time now without spilling from the overflow. The temp still isn't getting over 185 or so but is still puking. Could it be that there is too much coolant in the radiator? How high should the level of coolant be in relation to the overflow?still no symptoms of a bad head gasket...

 

[blizzardwarrior7]

Still wondering if the level of coolant in radiator is causing it to come out the overflow, I don't want any more responses telling me you think the truck has a bad head gasket or a crack in the block, it doesn't have any symptoms of any of these things and isn't overheating, just would like to know how full the radiator should be.

 

[armytruck63]

With the truck cold and not running, you should be able to see some coolant when you take off the radiator cap.

My dad's WWII GPW will barf out some coolant if you fill the radiator up to the top. Once it reaches the level it likes, it stays there, runs cool and doesn't spit out anymore coolant.

 

[blizzardwarrior7]

OK, sounds like that was the problem we had it filled to about 1 inch from the top. Will find out tommorow.

 

[topo]

on my m211 I keep the coolant just where I can see it in the fill cap . because the presser relief is just a little higher then that . and any coolant at that level will just get blown out . so keep the coolant below the presser relief and you should be fine .

 

[m1010plowboy]

Overheating,

Did you get that solved yet? My 6x has held rad fluid levels right to the top unlike some GM's that, as mentioned before, puke fluid until they are at a level they 'like'.

I really hope it's an easy fix for you! We did a new rad in a truck and one of the guys left some plastic packaging in a line before putting a hose on. Once we figured the rad was cold we just pulled everything and while removing a hose the red plastic cap fell out of the rad.....funny.

Put it all back together got it running great........then the fuel pump went........even funnier.

Found a rad assembly in the pile yesterday.......let me know if I should save it'

 

[butch atkins]

on my M211 when i got it ,it would only circulate coolant under pressure when hot,when it was cold i pulled the lower rad hose, the rad was so stopped up coolant wouldnot run out the bottom rad hose,had a new core put in,300.00 and no problems since,that was in 1992,so pull the lower hose and that will tell you if the rad core is stopped up,some will run out of the lower tank but the upper will remain full,good luck and keep posting