98 4.0

Doing the thermostat tomorrow.

My plan is to clean the engine side with a wire brush or sandpaper, then replace the housing altogether, but I have a few questions.

When I pull the temp sensor to put it in the new housing, do I need to apply the red loctite stuff?

Also, I am using the gasket that came with the Tstat. Do I need to apply rtv as well? If so, what kind and how much?

Lastly, what is the torque specs for the bolts on the housing?

Thanks

 

I would just use Teflon tape for the temp sensor. In regards to the gasket, I am assuming you got the correct gasket for your housing (Fel-Pro 35024 ?). I wouldn't use rtv, just put the Tstat in the right direction and torque the bolts down to 20 Nm.

 

Just did this yesterday. You can clean the engine side with what you mentioned but be very careful you don't get sand and/or wire up in the engine as there will be coolant still in there for it to float in. I just used a razor blade and got it as smooth as I could with that. The gasket will make up for slight irregularities so it doesn't have to be glass smooth. Definitely wouldn't use red loctite just use teflon tape as the previous poster suggested. I've changed a number of thermostats in my time as well as valve cover gaskets etc and had a few problems with leaking afterwards when I didn't use silicone on the gasket. I got some gray colored Permatex gasket maker which specifically said it was for water pumps and thermostat gaskets and covered both sides of the gasket with that and it worked great for me. Aside from making a good seal it is sticky enough it holds the gasket where it belongs while you put the bolts in. A dry gasket seems to keep slipping out of place for me if I don't use something on it.

Torque for the housing bolts is 13 pounds.

 

I know others do it, and it can work out just fine, but personally I would NEVER use sandpaper or wire brush on any gasket surface. Use a razor blade held vertically and "swiped" side to side to take all the big chunks off. Then follow up with a brillo pad to get the surface perfectly clean. If done right, neither the razor blade nor brillo pad will scratch, score, or pit your gasket surface.