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  #1  
Old August 13th, 2017, 07:33
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ehall ehall is offline
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radiator outlet temp to water pump

Anybody have a meat thermometer they can stick in the radiator near the outlet to the water pump? What temperature are you seeing after engine has warmed up? and what is the ambient temperature?

I have radiator inlet temp of 240 max dropping down to 100 at the outlet, so radiator is shedding 140 degrees, but that is with both fans running. With the aux fan disconnected the outlet temp is about 130, so primary is only shedding about 110 degrees by itself.

I have a dual electric setup that I have been using for 10 years, ran it in 100+ weather in highway and city traffic, trails, all over the place. Blew the fuse on it last year in a mud hole, running hot ever since. Not sure its still working.
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Old August 13th, 2017, 07:44
trippled trippled is offline
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Re: radiator outlet temp to water pump

Sounds borderline clogged? I've never seen a radiator drop that much heat unless there was a problem. Usually only 30-50 degrees. If you use your temp gun and go up and down and across the radiator do you see large jumps in temp? I usually check cars at work this way for failing radiators.
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Old August 13th, 2017, 10:45
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ehall ehall is offline
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Re: radiator outlet temp to water pump

Radiator is a Mopar HD that I bought last year. I have flushed it a few times, nothing in it but 50/50 coolant. Fins are not clogged.



Trying to figure out why the coolant is so hot coming out of the motor, figure I need to get the temperature down on the supply side?
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Last edited by ehall; August 13th, 2017 at 10:52.
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Old August 13th, 2017, 11:17
Jeep Driver Jeep Driver is offline
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Re: radiator outlet temp to water pump

Quote:
Originally Posted by ehall View Post
Radiator is a Mopar HD that I bought last year. I have flushed it a few times, nothing in it but 50/50 coolant. Fins are not clogged.



Trying to figure out why the coolant is so hot coming out of the motor, figure I need to get the temperature down on the supply side?
If those numbers are correct, your thermostat sucks.
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Old August 13th, 2017, 11:25
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ehall ehall is offline
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Re: radiator outlet temp to water pump

The thermostat that's in there is best of three Stant Superstat, measured in boiling water (opened the most and the longest).

Temps at the thermostat housing are usually in the 220 range but it spikes under load (see the MAX indicator on the 240 reading). At idle temps will drop. When I start moving from a stop light the temp drops from cold coolant rushing in (higher RPMs) but then climbs again because of the load.

Head has been cleaned, tested, resurfaced. Block was flushed. Muffler was replaced, cat removed (temporary), exhaust header replaced. Transmission was running hot (OD slipping) and was replaced. Radiator replaced last year. FlowKooler water pump and best Stant I can find.

Trying to figure out why the temps are so high.
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Old August 13th, 2017, 15:31
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ehall ehall is offline
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Re: radiator outlet temp to water pump

Quote:
Originally Posted by trippled View Post
Sounds borderline clogged? I've never seen a radiator drop that much heat unless there was a problem. Usually only 30-50 degrees. If you use your temp gun and go up and down and across the radiator do you see large jumps in temp? I usually check cars at work this way for failing radiators.
The plastic tanks are consistent vertically as measured with infrared. Sides and middle fins are consistent vertically as measured with meat thermometer.

Its possible that everything is partially clogged in equal amounts

The temperature drop could be legit since both fans are running full blast.
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Last edited by ehall; August 13th, 2017 at 15:55.
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Old August 13th, 2017, 18:45
rsadler rsadler is offline
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Re: radiator outlet temp to water pump

Could the lower radiator hose be collapsing and restricting the flow? A 134 degree delta t on the radiator definitely indicates low water flow.
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Old August 13th, 2017, 19:11
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Re: radiator outlet temp to water pump

Lower hose has a spring in it. I might be able to video record and see if its collapsing any.
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Old August 13th, 2017, 21:17
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Ecomike Ecomike is offline
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Re: radiator outlet temp to water pump

Try it with no T-stat or try a Murray (made in Isreal) T-stat. Is the water pump defective? What year is it?

That means there is way too little coolant flowing, thus the radiator is clogged or the pump is not pumping or the T-stat is not opening all the way, or a combination.

Mine was similar, not as bad when 2/3 rds of the tubes in my 20 year old OEM radiator were blocked. But it was about 50-60 F drop.

Once I had all the air out of the new radiator, I saw only a 20 F drop across the inlet to outlet at idle. At first I thought something was wrong, but it was right as it no longer overheated. The problem is we can measure coolant flow rates, and the delta T temps do not tell the entire story as you just discovered!!!

If I race the engine some I can increase the drop some for a short bit, so the range of the differential (drop inlet to outlet) is 20-30 F, when the flow rate is normal (idle to 2000 rpm)!!!! I have confirmed this with working (and one that was 2/3 rds blocked) Renix over the last 10 years.

Try it with no T-stat and then, or try, a Murray (made in Isreael) or OEM T-stat. Is the water pump defective? What year is it?

Quote:
Originally Posted by ehall View Post
Anybody have a meat thermometer they can stick in the radiator near the outlet to the water pump? What temperature are you seeing after engine has warmed up? and what is the ambient temperature?

I have radiator inlet temp of 240 max dropping down to 100 at the outlet, so radiator is shedding 140 degrees, but that is with both fans running. With the aux fan disconnected the outlet temp is about 130, so primary is only shedding about 110 degrees by itself.

I have a dual electric setup that I have been using for 10 years, ran it in 100+ weather in highway and city traffic, trails, all over the place. Blew the fuse on it last year in a mud hole, running hot ever since. Not sure its still working.
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Last edited by Ecomike; August 13th, 2017 at 21:26.
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