So i changed my thermostat out with the 203* and billet housing almost a week ago and today i noticed my coolant bottle kinda low and i saw coolant around the thermostat housing. I pulled it all back apart and the gasket somehow made it way ontop of the thermostat. I put it all back together right and it still seems to be leaking. Anyone have problems with this before?

 

Did you use a little Permatex to help hold it in place/seal it up?

 

Everything i read said not to use any type of sealant on the thermostat

 

The gasket belongs on top of the thermostat. Between the stat and the housing.

 

The next time you have it apart to fix the leak I suggest reinstalling the OEM thermostat...your top compression rings will say "thank you" and they'll reward you by not wearing out as quickly as they otherwise would with the hotter 203* stat installed!

 

lol makes sense why it was on top when i took it apart now..but it was still leaking with it put together right

 

does the extra couple degrees really affect the rings?

 

Just wanted to make sure you didn't put it back in underneath.

I agree with Gene. I have a new 195° stat waiting to go in.

 

I would also suggest not using the 203* t-stat. I have one in and will be changing it soon because old temps are just to high, especially when towing.

 

I did just put it back together with the gasket underneath the thermostat because i thought thats why it was leaking. I guess ill flip it back around and put the old one in and see if it still leaks

 

If it still leaks do use some high temp RTV. Just a small bead so it will only be in contact with the metal sealing sufaces and not the o-ring. Let it set up before starting. Many have done this with that leak and no ill effects. Might as well get a new 195° stat. Take the old one or the 203 with you to be sure the replacement is the proper length.

 

okay thanks for the input

 

I will also be changing out my 203 stat. New from Ford has the o-ring built right into the stat.

 

Most emphatically yes it does ...and by using a 203*F stat you also give up a significant amount of coolant reserve heat capacity that might come in handy when towing long grades in the summer! Here's a quote from a paper I'll be discussing in detail on my "wear and tear" thread that reports measurements of piston ring and cylinder liner wear...

..."To avoid scuffing of the ring and liner typical TRR temperatures in diesel engines are kept near 200*C by circulating coolant through the cylinder head. Tests conducted at 260*C have shown that the rings and liners experience wear at least 100 times greater than at conventional TRR temperatures."...

...and TRR means... Top Ring Reversal ...which I've already discussed some in that thread and I'll be covering it in more detail in my next installment!

 

203* is leaving my truck about the same time as Clay's.