helllp with cooling issue

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72golddustermike

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this is a 74 dart sport mild 318 auto . its goes up to around 225 it has a 180 stat. we tryed new stat no change changed radiator no change swapped no gauge no change. wierd thing is top hose warm botom hos warm but you can drain coolant and its cool out of peat ****, with both radiators one is a new one
 
72golddustermike said:
this is a 74 dart sport mild 318 auto . its goes up to around 225 it has a 180 stat. we tryed new stat no change changed radiator no change swapped no gauge no change. wierd thing is top hose warm botom hos warm but you can drain coolant and its cool out of peat ****, with both radiators one is a new one
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What kind of gages do you have? When I got my autometer gages, I plugged the temp gage into the sending unit I had at the time, and it showed about 225 or so also. When I put the sending unit that came with the gage, it went to normal. Might try changing the sending unit if you haven't
 
A 180 degree thermostat doesn't keep your coolant at 180 degrees. It opens to allow flow at 180 degrees. Your car will normally run hotter. From what you are telling us I would question the gauge's accuracy. 225 is over the boiling point. When you open the cap, the petcock, whatever and release the pressure, it should begin boiling immediately at 225 degrees. That is doesn't and the coolant from the petcock is cool tells me you should try another gauge.
 
its doin this sitting in shop has mopar viscous fan 3 core factory radiator. what baffles me is the watter being cold when i drained it even though both hoses warm
 
idleing with no cap watter is warm at top popped thermostat housing off immediatly measured with thermometer it read about same as gauge i had already replaced gauge and sending unit this is a new water pump installed about a year ago but car has only been drove arount shop
 
1968FormulaS340 said:
Take it out and drive it. A fresh engine idling in a garage is not a good indicator of cooling system performance.
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Agreed. Some vehicles will run hotter with the hood up while others run cooler with the hood up. A fan shroud a foctor too.
 
There are two different pumps and fans for SB"s . The newer pumps and fans are for a serpentine belt and spin in the opposite dirrection. Make sure you have the right pump and fan for the dirrection your spinning them. Just something to check. I have seen this done before and it will get hot and not circulate properly with the wrong pump,
 
I'd bet the impeller came loose from the pump shaft, or the thermostat is upside down.
 
When everything in the cooling system looks good and seems to be functioning properly its time to look at the timing and carb. If your carb is running to lean its going to run hot. The opposite if its too rich.
 
i went and tested again this morning like i said without thermostat coolant circulates. i have tested stat in water on stove opeened when water was 182 degrees according to thermometer in pan of water. if i put stat in with spring toward intake it will not circulate looking in radiator with cap off. pump is a reman from carquest.
 
Based on what you're telling us, it really sounds like the temp sending unit. Some of the cheap part store ones are way off. I've bought new ones and had them not read right. I know there's a way to check it by reading resistance through it, but I don't know the exact procedure off the top of my head.
I think they only cost about $5-10...worth a try.
 
Please don't take this wrong, but: As a former Factory Field Service Rep, sometimes it's the simple things that are overlooked by technitions Have you checked the temp with anything beside the gauge in the car? Maybe it's NOT getting hot after all. Temp senders WILL go bad and an alternative measuring devise will tell you.
 
1968FormulaS340 said:
Take it out and drive it. A fresh engine idling in a garage is not a good indicator of cooling system performance.
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Agreed. Get the coolant flowing. Also, maybe your t-stat is not opening. Back when I was in parts, there was a 39% failure rate right out of the box on t-stats. Drive it and see. Possibly there is an air bubble and driving could help work that out as well.
 
72golddustermike said:
i went and tested again this morning like i said without thermostat coolant circulates. i have tested stat in water on stove opeened when water was 182 degrees according to thermometer in pan of water. if i put stat in with spring toward intake it will not circulate looking in radiator with cap off. pump is a reman from carquest.
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The spring is down towards the engine / intake and the pointy top towards the radiator hose. It will not circulate until it opens.
 
Like one of those wierd movies where one would never guess the outcome because there were a set of circumstances that the watchers were not aware of.

Those movies suck, right?
 
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