Radiator won't take fluid

[RenegadeActual]

I am wrapping up the headgasket job I did on my M54A2, I thoroughly flushed the radiator with a hose, replaced every hose on the engine, flushed the engine real good with water, drained everything and now I am pouring coolant into a empty system, and it will only take 2 gallons. It's overflowing out the fill port and I removed the upper hose and it's bone dry. Is there something odd about these radiators, is the upper tank separated into 2 chambers? I'm at a loss here.

Either the radiator is completely plugged, even tho I was able to get the hose water to flow out all 4 ports in it just 20 mins prior.... I had flushed it with the radiator removed from the truck.

 

[Karl kostman]

It sure sounds like you have an air block very likely in the radiator itself. This is what I would try, open the drain valve on the bottom of the radiator and start filling, are you getting coolant out of the drain valve? If so OK you getting coolant that far. Then I would start loosening hoses on the engine and even the drain valve on the block and as you fill watch that block drain and when coolant starts coming out there close it. Then keep the coolant hoses loose on the engine and as you fill the system listen for air being forced out of you lose hose connections and seal as the coolant level is rising intill you get to the top coolant hoes what wherever that is. This method will likely allow the air to escape as your refilling the system.

 

[RenegadeActual]

Well I turned in for today. I was squeezing the lower hose and nothing. Litterally the coolant was filled to the radiator cap and I can pull off the upper hose and not a drop. I can put my hand into the upper hose port in the radiator and its bone dry. Either the upper tank has 2 chambers or the radiator is completely plugged. Im going to pull it back out monday and take it to a radiator shop to have it rodded and pressure tested. Dont want to blow another head gasket.

Sent from my SM-S918U using Tapatalk

 

[US6x4]

No idea about the M39s, but my M809 has s quarter turn vent valve on the reservoir tank hose near the upper radiator hose that must be open when filling so that the coolant can displace the air as it fills.

 

[RenegadeActual]

So, turns out the cooling system on this truck had been neglected by the previous owners. The radiator shop told me they vatted and flushed the radiator 3 times and it was still 70% plugged. So they rodded it and repairing a little tiny hole in a tube and now it took all the coolant just fine.

 

[RenegadeActual]

BTW
Serck Radiator
424 E Baseline Rd
Mesa, AZ 85204
(480) 926-3555

They did a great job and only charged $175 to rod, flush, clean, and paint the radiator.

 

[US6x4]

Thanks for reporting back. So many posts ask for help troubleshooting and then never share the final findings.

 

[jimmr]

i'll second that, nice to hear the cure for issues we all run into here and there. thx