1977 Dodge Truck coolant not circulating

Tiny
THE BIG RED ONE
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  • 1977 DODGE TRUCK
Engine Cooling problem
1977 Dodge Truck V8 Two Wheel Drive Automatic

the truck has a 440 motor.I changed the thermostat, flushed the radiator, back flushed the radiator, checked the radiator for flow by pulling off the bottom hose from the radiator which dumped water from both the motor and radiator very quickly.I also just put on a new water pump. The truck still goes to hot the temp gauge in about 5 minutes of idling which is what it was doing before I did all that. Now my question is why would the top radiator hose be too hot to hold and yet the bottom radiator hose is cold to the touch. Before I started all this one person said I may have a blown head gasket.I talked with someone else today who did not know what to check next but did say that if I did have a blown head gasket the hoses would be both hot and not just the top hose. Any help would be greatly appreciated as I do not have a fortune to spend on this truck.
Sunday, July 26th, 2009 AT 12:56 PM

5 Replies

Tiny
DOCFIXIT
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Hi
Think the radiator is so calcified the flow tubes are restricted and flow is not sufficent. Also maybe air lock in block remove cap run til warmed up do you see coolant flowing? Air bubbles? Does coolant overflow when engine reaches op temp?
Let me know
THanks for donate
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Sunday, July 26th, 2009 AT 2:09 PM
Tiny
THE BIG RED ONE
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The coolant does overflow when the motor starts to reach temerature when I have the cap off.I did look at other posts and one of them described what seemed like my same problem and they were told by a carpro to replace both hoses. Now this evening I was going to replace the hoses but was given the wrong upper hose. When I took off the lower hose I checked the outlet from the motor for the lower hose and there was some grit, rust or whatever it was on the inside of the outlet. What I did was take off the thermostat and put my garden hose to the outlet on power wash. First I just let it flow thru and then I covered the bottom outlet with my hand until water started to come out of the thermostat outlet. Then I released my hand with the hose still running. Not sure if that did any good. Anyway yes ithe radiator does overflow with the motor running if the cap is off. You speedy reply is much waited on as monday I will be exchanging the top hose and it would be nice to know if I am once again just wasting my time and money. The view of the radiator thru the opening for the cap does not seem to show anything crusty inside the radiator.I await your reply. Thank you. Maybe the fact that the truck sat for about 3 to 5 years with just being started on ocassion to keep battery charged might be a factor.I got this truck from where I work as it was just sitting and they got tired of paying the tabs and insurance for a truck they no longer used. What is the vapor lock you talk about and how do you fix it?
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Monday, July 27th, 2009 AT 1:36 AM
Tiny
DOCFIXIT
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Having set that long water jacket is most likely rusted and preventing flow. Have you tried a chemical flush?
Radiators clogg up at the bottom reducing ability to cool. Vapor lock is after pump replacement air is traped in block and prohibits proper filling. When started air expands pushing coolant out. Jack up front of truck run with cap off to expel air.
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Monday, July 27th, 2009 AT 3:19 PM
Tiny
THE BIG RED ONE
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What type of chemical flush are you talking about?Is it for the motor specifically or is it a radiator flush?I did put in a flush for the radiator. It was a prestone flush for neglected radiators but it said to run the motor in regular driving for 3 to 6 hours but I can not run it anywhere near that long with out the motor getting very hot. Probably 10 minutes tops. Also I will try parking truck up hill with cap off as right it is parked facing downhill. Thanks and I await your answer about the chemical flush.
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Monday, July 27th, 2009 AT 10:06 PM
Tiny
DOCFIXIT
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Flush you used would work but not if it won't circulate. On the block about mid way below exhaust and couple inches up from oil pan. Find a hex head block drain one on each side. Remove and see if all cloged up and if water flows out.
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Tuesday, July 28th, 2009 AT 9:14 AM

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