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Overheating issue

mopar951

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Hi everyone I’m having trouble with my 69 coronet it has a 318 and the trouble I’m having is it’s overheating on trips that are like 20-30 miles it has a new thermostat new upper and lower radiator hoses and new coolant I took the rad out a flushed it and nothing really came out it does have a newer rad cap I have a video of what it’s doing in the radiator with the cap off but it’s just swirling around it’s not flowing any insight I was thinking water pump?
 
To be sure the radiator is not the problem it needs to be rodded out by a radiator shop.
They take the tanks off and clean out the core properly.
 
Hi everyone I’m having trouble with my 69 coronet it has a 318 and the trouble I’m having is it’s overheating on trips that are like 20-30 miles it has a new thermostat new upper and lower radiator hoses and new coolant I took the rad out a flushed it and nothing really came out it does have a newer rad cap I have a video of what it’s doing in the radiator with the cap off but it’s just swirling around it’s not flowing any insight I was thinking water pump?
When you say swirling around, is it not doing that at idle? Or just at throttle?
 
My "66" with the factory 361, was easily running hot.
I bought a radiator shroud and that fixed it.
 
Pull the radiator and have a radiator shop clean it out. Fan shroud is also a big help. Put a spring in that lower hose to prevent collapse. and get a FlowKooler water pump with hi flow 180 thermostat. .
 
My experience with 318’s overheating was most always a clogged radiator.
 
You might check out the search feature on this site, cooling/overheating issues are a common posting with many tips on solutions. IMO, before getting too deep, look at the elementary things first. As you point out, a collapsing lower hose isn’t good. Getting a correct one is important, proper length and curve. You could insert a spring in it to prevent it from collapsing. This alone might be the problem.

Getting air out of the system that may be trapped is important. Air can get trapped when changing the coolant. Having replaced the lower hose, a lot of coolant in the block drained out. Good time to do a system flush, using a flush solution if you can do it; I use a back-flush connection, cheap at an auto store. Re-filling the system takes time necessitating adding more coolant, once the t-stat opens the radiator will drain down needing to add more. Don’t overfill the radiator during the process or you’ll get a mess. When I know it’s getting near to full, I use a 32oz wide-mouth milk or soda bottle with the bottom cut off for filling, if air is trapped it will cause some purging of coolant up into the bottle and may settle back down if you haven't put too much in.

Checking for water flow you can observe it by giving some slight throttle, too much and likely coolant will puke out. Flow will be noticeable under slight throttle. If the pump is faulty, typically it will make sporadic ticking or rattling noise, or leaking from the weep-hole, and another check with engine off is to see if there is fore-aft play with the fan. Full coolant should be an inch or so under the opening, not up to it.

Ok, basic info, but don’t know what experience you have, so pardon if I’ve insulted your know how.
 
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