Running hot randomly after new water pump

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Ramrob20

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The water pump went out 3 months ago on my 2014 Ram Hemi at about 135,000. I replaced it with a MOPAR pump, thermostat and coolant. Prior to it going, the truck would run about 199-203 and since replacing it, it runs about 204-208. And it will also randomly run all the way up to 221 until the aux fan kicks in and it comes back down.

What is making it run hotter than before?

There doesn't seem to be any air in the system, but how am I sure? I did not replace the clutch fan as it seemed to be functioning properly, could that be it?

Pic of temps from this morning.

IMG_8389.jpg
 

DILLIGAF

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The fan clutch should've never been put back on ;)

Might just be a slight variation from one Thermostat to the other or Still a bit of air in the system.

Burp it gain just as a precaution.
 

DILLIGAF

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I mean you dont need it. :headbang: :headbang: Tons of folks on here just delete it without even doing the V6 fan swap.
 

Burn2k12Ram

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What t-stat did you go with? Those have been known to be bad new. when up to temp take a temp gun and measure the temp of the top hose and bottom. Will tell you if it is opening properly or not.
 
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Ramrob20

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What t-stat did you go with? Those have been known to be bad new. when up to temp take a temp gun and measure the temp of the top hose and bottom. Will tell you if it is opening properly or not.
It was a Mopar brand. I could try a new tstat. What should readings relatively be with a temp gun on the hoses?

EDIT: At idle and truck up to temp (203*) the top hose is ~155* and the bottom hose is ~110*
 
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Dean2

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It was a Mopar brand. I could try a new tstat. What should readings relatively be with a temp gun on the hoses?

EDIT: At idle and truck up to temp (203*) the top hose is ~155* and the bottom hose is ~110*
Tells you the T-stat is closed at 203 or the upper hose would be 203. What does the T-stat area around the housing read before the T-stat. My 2021 2500 has a 215 Degree thermostat, actually says 102 Centigrade, so it won't normally open till the coolant hits that temp. That is without getting into the whole electronic opening stuff on them.
 
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RedSRT4Me

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The water pump went out 3 months ago on my 2014 Ram Hemi at about 135,000. I replaced it with a MOPAR pump, thermostat and coolant. Prior to it going, the truck would run about 199-203 and since replacing it, it runs about 204-208. And it will also randomly run all the way up to 221 until the aux fan kicks in and it comes back down.

What is making it run hotter than before?

There doesn't seem to be any air in the system, but how am I sure? I did not replace the clutch fan as it seemed to be functioning properly, could that be it?

Pic of temps from this morning.

View attachment 510063

Still have air in the system. Bleed the system and get the air out.
 

Dodge 1500 4X4

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Remove the radiator cap and squeeze the upper hose several times, also put your heat inside truck on High to get the antifreeze to flow through heater core that may help in burping!!
 
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Ramrob20

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Did some troubleshooting this morning. Ive determined that I don't think the thermostat is opening, let me know if you agree.

1. Confirmed no more air in system (best I could).
2. Filled reservoir tank to correct height (it was empty)
3. Let truck idle with radiator cap off and heat on.
4. Truck idled until it reached 206*

At this point the radiator overflowed out of the cap and all over the floor. The top hose measured 160*, the bottom hose was 110* and the thermostat housing was 150*.

This leads me to believe the thermostat is not opening correctly and is also probably getting stuck closed during the times it reaches 221*.

Agree?
 
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