rebel05

I just replaced the water pump and the thermostat because it went out a few days after i flushed the block and changed the engine coolant.I filled the truck up with the coolant that i saved though.I did lose some but i added some again but i still know it will go down in the morning but the only question i have since i know there is some coolant that i know i still need to add is that when i drove it for a distance the temp gauge would move back and forth slightly.It would go up a bit past 190 then back to normal then cooler then it would go back a bit past 190 then go back to cool.Is this normal.I doubt the thermostat is sticking.It could be that i still need to add some coolant but i dont think that would explain the gauge going back and forth.

Thanks

Clunk

In cold weather, mine doesn't get steady unless I'm running steady speed for 30 to 45 minutes on the interstate. These Dodges have a good radiator.

John Faughn

From what I've seen , its not uncomin for the thermostat to cycle , that makes the gauge follow .

rebel05

is it true that the water pump or thermostate doesnt need any gasket silicone sealing? I looked and didnt see any when i removed them.

I bought a tube but i never used any because i thought it would interfere with the gasket being seated right and it might start leaking.Now I replaced it at 103K miles right now.I heard thats not uncommon for a pump to go bad at 100k. So im not too concerned about the life of it.Just felt kind of bad that it went out right after i changed the coolant.It wasnt too expensive since it was only 55 dollars.The brand is master and has a lifetime warranty.I noticed on both of my dodges that the gauge always moved so Im assuming that is normal?

Thanks for your time!

John Faughn

If you bought the pump from Cummins then I would say you do not need the silly cone , but the master brand is just a rebuilt with a sticker on it saying master .
Not realy sure about what you have , the origanal should go longer , but there's no telling what was in your truck & what kind of life it had [ abuse or not ] .

ib516

Exactly, especially with a new 'stat.

rebel05

yeah but it always used to stay below 190 even when it did cycle but now it will go a little bit over 190??

biododge1

small pocket of air in system, add coolant to reservoir

lovinCTD59

Sounds right with it cycling like that. Its possible that your old stat (spring) was weak and started to open before it should and your new stat is stronger and holding it until 190+ which if you got the 190 degree stat it it sounds about right. When its cold out my truck takes a while to get up to 190... It goes a little past 190 then the thermostat opens up and then it hangs just under 190 unless im in the city driving around then it stays cooler yet....

rebel05

okay thanks.

CJ

I run a piece of cardboard in front of the radiator in the winter. The gauge goes up above 190 for a couple seconds, drops to 160 or so then settles around 180. In the summer w/out the cardboard it fluctuates a lot.
CJ