Running hot randomly after new water pump

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Dean2

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Oh jeez, that sounds expensive. I'm not a mechanic and too old to do that job. But thanks for the advice.
it would take a good rad shop maybe two hours. SB is spot on, it is well worth doing. Otherwise the core just plugs back up.
 

GTyankee

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Jack W,
Consider seriously taking the radiator to a Radiator Air Conditioning shop,
I think you will find that you will save money by having the radiator cleaned out properly. If the shop tells you that they can not fix it, they can get the radiator for much less than a auto parts store or general repair shop.
 

GTyankee

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I don't about Chrysler vehicles, but some vehicles have a pin or a notch in the housing.

It is not like Indexing spark plugs, where you try your best to point the side electrode opening at the intake valve
 

Sherman Bird

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it would take a good rad shop maybe two hours. SB is spot on, it is well worth doing. Otherwise the core just plugs back up.
I went through this the hard way years ago.... on a RAM. The original problem was a heater that didn't put out more than tepid temperatures coupled with intermittent overheat, at least according to the pegged gauge on the dash.

Customer OK'd flush of the heater core, an new t-stat, and a new radiator cap. Problem was only marginally fixed. SO, we put in a mechanical temperature gauge and drove the truck. The temp maxed out at about 240..... right on the cusp of danger to the engine. The true temp at about 225 would peg the gauge, and that is not true overheat on a modern engine, at least not really high enough to do damage.

Problem was, as we dug for info from customer (They rarely tell the entire truth up front) we found out that this was a problem which had existed over several months, and, other shops had attempted repairs (t-stats).

We ultimately figured out that the radiator was restricted, and replaced it. Problem solved..... for about a week... and here it came back with the original problem all over again.... Clogged heater core and recontaminated radiator. HMM!

By this time, the head gaskets were giving up and we were observing froth at the oil fill cap, and slight milkshake color to the oil. SOO, we replaced the head gaskets! During the time said cylinder heads were off, my technician pointed out that the rear coolant passages were totally clogged with cruddy debris consistent with coffee ground like rust scale/ particulate. This clogging was at the rear of the block up to the gasket surfaces of the block... OH! NO!

So, we reassembled the engine, ran the truck over a ditch like depression behind the shop, and I removed the starter and rearmost freeze plugs. I ran a garden hose to the truck, fashioned a nozzle (custom) and crawled underneath and flushed out tons of crud... and got mighty wet and filthy!:)

Afterwards, we replaced the thermostat with MOPAR part, ditto for the cap, and filled the cooling system. Problem was solved!

As a side note: The truck's owner had been convicted of DWI, and had one of those breathalyzer interlocks that one had to blow AND hum into in order for the truck to start. HOW annoying! I bypassed it for my own convenience, and never dreamed that it would communicate this "bypass" to the powers that be! After a lengthy conference phone call, I got him out of trouble. Those idjits wanted to come after me! I told them that I never had any DWI, or those problems, and refused to let them put me on a guilt trip over it! I did find out that the unit had a 1-800 number on it which I could have called to get a temporary "code" to enter for repair purposes.
 
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Jack W

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I talked to a rad shop owner who told me dodge had a problem several years ago where the cast sand didn't get completely flushed out and caused problems like this. He's going to work on it next week for me.
 
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From what I understand HEMIs are bad for over-heating due to them being sold with a 203 degree thermostat.
Go to the auto-parts store and get a 180 degree t-stat. You have to ask for them but they do carry them.
I put one in my 2012 ram and by the time it hits anywhere close to 200 (190 ish) the t-stat is already open.
This is a good performer upgrade for your engine also
 

Sherman Bird

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Using an infrared thermometer is great for reference purposes but they can be really inaccurate especially when reading through a moving air stream. Couple that with your trying to read through rubber(it's an insulator).
Stick a surface probe on the top of the thermostat housing and/or the metal part of the radiator as close to the upper hose as possible.
My Multimeter came with a surface temp probe. It has been valuable in proving exactly what you say, but then, not every one has this knowledge! Thanks for sharing!
 

16MaxSteelOutdoorsman

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I just had my water pump replaced under warranty along with the thermostat and looks like the temp sensor. Now the temp bounces between 203-213 F. I did heat it up and open the cap and there were quite a few bubbles escaping but probably didn't get it all out.

Also, at three years and about 50k mi, I asked the dealer to change the coolant, they said it was good for 5 yrs/100k mi. So when the vehicle was 5 yrs, I found that the coolant had sludge around the radiator cap. So much for long life fluids. From now on, I change it like I always did before, this is the first time I've ever had to replace a water pump on any vehicle.
 

06 Dodge

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I just had my water pump replaced under warranty along with the thermostat and looks like the temp sensor. Now the temp bounces between 203-213 F. I did heat it up and open the cap and there were quite a few bubbles escaping but probably didn't get it all out.

Also, at three years and about 50k mi, I asked the dealer to change the coolant, they said it was good for 5 yrs/100k mi. So when the vehicle was 5 yrs, I found that the coolant had sludge around the radiator cap. So much for long life fluids. From now on, I change it like I always did before, this is the first time I've ever had to replace a water pump on any vehicle.

I have had coolant last over 10 years without sludge, sludge is possible due to someone topping off rad with the wrong type coolant i.e. HOAT in a OAT system, cheap coolant or using tap water instead of distilled, as for water pumps some last 15 years other last 4-6 years some even less...
 

Sherman Bird

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From what I understand HEMIs are bad for over-heating due to them being sold with a 203 degree thermostat.
Go to the auto-parts store and get a 180 degree t-stat. You have to ask for them but they do carry them.
I put one in my 2012 ram and by the time it hits anywhere close to 200 (190 ish) the t-stat is already open.
This is a good performer upgrade for your engine also
One could put a 100 degree thermostat (not saying one exists) and still overheat from other issues like a radiator having a corrosive or alkyline coating. Just sayin'! 203 degrees is close to the industry standard to comply with EPA emissions. Been that-a way for north of 35 years now!
 
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