I'm actually going to back down to the 195 when I do my radiator.

I'm running 210-215 on the highway with a 203 t-stat.

The old one I had was stuck open and I rarely saw above 210 on the highway unless it was 90+ out.

 

Yeah or if you want to be really sure it won't leak get a new neck for it. Of course make sure you're getting a new thermostat seal (they cost less than $5). I have had pretty good success just cleaning them up real good and making sure the bottom surface is flat. They tend to bend where the bolts go down through them. Put them on a heavy piece of steel and use a small ball peen hammer to flatten them out. They usually work pretty well that way. My truck has a custom made thermostat neck on it and I don't have to worry about it on mine, but I have had to deal with it on others....

Of course a little ford gray silicone doesn't hurt either so long as you don't go too crazy with the stuff.

 

Where do you get a neck? What is the part number?

 

Thermostat with additional info at the bottom of the page.

Neck info

These are from the Dieselsite link. I bought the 203*F thermostat a few years ago and it's still working great. I average 18 MPG combined city/highway driving unloaded and 13 MPG pulling my 24' travel trailer and needed gear.

 

4.10s or 3.55s?

 

I bought a thermostat from PePBoys but had no gasket ... maybe use the old gasket and thermostat?

I think I will sand down the neck and use permartex.

I could weld a bead and then grind it down !

But I think the lip sets on the gasket thermostat and very little on the water pump casing?

On Ebay there is a person selling a flange with bolts and "better" gasket for $32 steel and $40 for 304 stainless.

Search using this phrase ... Ford 7.3L Powerstroke Thermostat Housing Leak Fix Kit

Thank you for letting me know the proper name of this thermostat housing

 

Here is the sales "pitch " on EBAY

Use this kit to fix the thermostat housing coolant leak on your 1994-2003 7.3L Powerstroke engine.


On this engine, the easily bent Ford thermostat housing mounting flange is one of two sources for coolant leaks at the thermostat housing to water pump interface. The square cut o-ring that Ford uses is the other source. The Thermostat Housing Flange Reinforcing Ring, (THFR Ring) effectively stiffens the weak thermostat housing flange eliminating any chance of bending. No need to replace your existing bent housing as the THFR Ring will straighten it. The only reason to replace the housing is for excessive corrosion. Stiffening the thermostat housing flange also allows the use of an improved o-ring. The THFR Ring, along with this new style o-ring, effectively eliminates the thermostat housing coolant leaks that plague the 7.3L Powerstroke engine.



This kit was born from my frustration with the leaking thermostat housing on my own truck. No matter what I did, I could only get it to stop leaking for a couple months at a time. During that time, I installed several new Ford o-rings as well as two new Ford housings. I have been running this kit for over two years now on my truck without any leaks. I have also sold quite a few of these over the past couple years and have not had anyone come back with a complaint. Check my feedback to verify. The detailed instructions that come with this kit contain my email and home phone if you should have any questions. I'm confident this kit will fix your leak as well.



Kit contents: 1 - Installation Instructions

1 - THFR Ring

1 - O-ring

3 - Bolts



Additional replacement o-rings are also available for $1.00 each. You will want to replace the o-ring any time you remove the thermostat for cooling system service.





The THFR Ring in this kit is made of 304 stainless steel and will not corrode. For a cheaper option, please see my other listing for the kit with the THFR Ring constructed from mild steel.


Anyone tried this method?

 

I bought one of these and a new neck...
http://www.ebay.com/itm/Ford-7-3L-Powerstroke-Thermostat-Housing-Leak-Fix-Kit-Mild-Steel-/161124717998?pt=Motors_Car_Truck_Parts_Accessories&hash=item2583c815ae

 

Did it work?

 

I bought one of them and a new neck also. Works, no leaks anyway.

 

Did you go with the carbon steel or stainless steel Thermostat Housing Flange Reinforcing Ring?

The water pump seems to be aluminum so chemistry states there will be galvanic pitting corrosion on a high carbon steel part connected to the aluminum with H2O running thru it.

http://en.wikipedia.org/wiki/Galvanic_corrosion
I already have pitting corrosion on the steel thermostat housing.

It seems to me IMHO the ideal fix would be to have the thermostat housing and tubing be made of the same material as the water pump.

Aluminum.

This would eliminate the galvanic corrosion between steel & aluminum.

Of course the housing / tube could be thicker to compensate for the properties of aluminum vs steel.

Does anyone make an aluminum thermostat housing and neck?

An aluminum thermostat housing and neck will eliminate the corrosion.

 

Dieselsite sells one.. Billet..
Dunno if it fits our h2o pumps tho...
http://www.dieselsite.com/blackbille...athousing.aspx

 

I'm pretty sure I got the mild steel one Corey listed.

 

The dieselsite one is for the SD trucks, and is waaaay shorter than ours. You'd need a different top hose for sure.

This one: Thermostat Housing Ring is sold by Strictly Diesel, a supporter of many of the diesel forums.

 

The issue is the material.

basic Chemistry 101

Most chemistry is the exchange of electrons or the sharing of electrons

(Nuclear chemistry will not be discussed here)

Two dissimilar metal placed side by side ... in our case steel and aluminum have different number of electrons.

The weaker electron will be striped away IF we have some method to move the electron.

The radiator coolant has water in it ahaha ... a way to move electrons!

Most H2O is slightly positive ... thank you GOD ! (or we wouldn't be here)

as the fluid moves past the two metals the positive charged water builds up over the stronger outer electron metal then over the weaker electron and "strips it off into the solution" That's the galvanic corrosion or pitting corrosion you can see on the part of the steel tube touching or close to the aluminum pump housing.

So no matter WHAT WE DO IT WILL CORRODE unless we remove the dissimilar metal or put in an sacrificial anode.

A sacrificial anode (something giving up electrons easier than the metal we're trying to preserve typically ZINC) would not be a good choice since it will be entered into the coolant ... and contaminate it!
Hope this helps.