Temp gauge issue...

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Sep 24, 2006 | 11:17 AM

#31

Aramis

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I'm more inclined to sway towards a "lower temp t-stat". Reason i'm thinking this is when I flushed the coolant and re-filled the rad, started the engine, I had to way a while before the level in the rad dropped. When it finally dropped, I had to re-fill the rad. This tells me the t-stat had opened up and the engine had sucked the rad dry(well sorta)...

Another reason I think the t-stat operates: When I disconnect the top hose from the t-stat housing, the housing is full of liquid. If it was open, the water in the housing should have flushed along with the rest of the engine.

But like I said earlier, my infrared thermometer says' 170 both in the rad and on the t-stat housing, i'm thinking it's just openning too cold.

Sep 24, 2006 | 09:50 PM

#32

Aramis

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Well, a new thermostat did help...

Now the gauge actually makes it into the normal range, but on the low side of it, still, i'm happy about it.

I have another question though:
I test drove it to see how the new t-stat behaved, seems all ok, upon my return, I inspected the t-stat housing to make sure it was not leaking, I found no indications of a leak, but something dit get my attention. the gasket on the top is wet, and I could see 1 or 2 tiny tiny little bubbles... Is this normal? I'm guessing these gaskets expand and seal once wet but I prefer asking...

Sep 24, 2006 | 10:00 PM

#33

pawpaw

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From: SW Va

What was the temp range printed on the old thermostat???? Was it a Motorcraft????

What did the infared probe indicate your temps were with the new thermostat????

I don't know about your gasket, my 4.0L uses a rubber "O" ring for a seal.

In years past I'd butter both sides of paper gaskets with a thin layer of Loctite Ultra Blue RTV, before instalation & never had any weeping!!!!

Sep 24, 2006 | 10:12 PM

#34

Eric.S

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From: riverside

For thermostats i usually dont even use a pre made gasket, just rtv. Never had a problem with it either. Put it on there put the piece on and dont tighten the bolts very much (just barely make contact) until the stuff dries. Then torque them down as usual. If you torque them with it still wet then you'll smash all the rtv out.

Sep 24, 2006 | 10:16 PM

#35

Aramis

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The new t-stat is a 192F, the old one says 192 as well, but I know that the old one opened around 170, the new one opens around 190, so this is better...

If the weeping doesnt stop, i'll take it back out, and redo it with some rtv..
thanks guys...

Sep 25, 2006 | 11:07 AM

#36

Peter94

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From: St. Peter

i usually use the gasket and rtv, and just butter it up then let it get tacky so it sticks, then put it on. You just dont want chunks of rtv floating aroudn your engine.

Sep 25, 2006 | 10:24 PM

#37

MazdaRangerGuyInSTL

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The spring was weak in the old thermostat, causing it to open too soon.

Seen it many times. My B3000 stays on the cold side of normal during cooler weather, about right in the middle in the dead heat of summer.

As far as RTV goes.. I try to never use it. If I do need to use it I use just a little bit to hold the gasket in place, but if I can install the gasket without having to "glue" it on, I install it dry.

Alot of newer vehicles use O-rings instead of gaskets though.

Last edited by MazdaRangerGuyInSTL; Sep 25, 2006 at 10:32 PM. Reason: edit

Sep 25, 2006 | 10:35 PM

#38

Aramis

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Well I decided not to re-open it for now. I gave the bolts an extra little torquing today, can't drive it right now waiting on a part but if tomorrow all else flies ok, i'll be testing it out.
Currently running on water only, in case I have to dump it again. But getting a little nervous as cold weather is coming fast so it sleeps indoors but as soon as I can sign off on the t-stat, i'll but antifreeze and send it out in the driveway...

I'll keep you posted..