Just replaced the housing on my 2000 Coupe, which had not cracked (perhaps previously replaced?) but was leaking at the base.

The replacement is aluminum, and I also used a replacement aluminum housing for the thermostat (the piece that covers the forward side of the thermostat)

There is not even a slight amount of seal between the two aluminum pieces, and the thermostat failed to open. Fortunately was watching it carefully and noticed the lower hose was not warm when it should have been. So if I squeeze the lower hose, I can see coolant and air rushing out from between the two aluminum pieces.

I used a thin, paper looking gasket included between the two aluminum pieces.

My questions are:

1. Am I not supposed to use the two aluminum housings together?
2. Do others use the plastic thermostat cover (that connects to the lower hose) with the aluminum replacement housing?
3. Is it correct to think the thermostat didn't open because of the leak (i.e. couldn't get hot enough) Or is there another problem?
4. Any other advice?

Thanks,

Tips- a clawfoot wrench didn't work for me with the rear housing bolts. Fortunately, the plastic housing that's in the way is cosmetic (and hidden), so I ground/melted a groove with a Dremel so I was able to use a regular socket and extension on them. 1/4" drive helps too as the shaft and socket are smaller.

There's an easily-found website that talks about removing the fan housing. I found no reason to do so. Just remove the top hose first and the lower hose at the thermostat is easily accessed.

 

if you remove the metal plate on the front of the intake the back two bolts are easy to get out.

 

I just replaced my thermostat tower and the hose connection piece with the aluminum version and if I remember correctly there was a 'O' ring type seal.

Jaguar XJ8 XK8 Aluminum Thermostat Housing Kit AJ82217 | eBay

Your kit not have the rubber seals?

 

There is a rubber seal for around the thermostat, since I got a new thermostat it had its own o-ring. As far as I can tell, it's the same as what I pulled out. Taking it apart now.

Update: Apparently it's easy to mis-seat the thermostat, so the two parts were not able to seal.

Have another new problem with misfire, spilled coolant shorting something?

Update: With some horror, I realized the plastic cover I was cheerfully grinding WASN'T A PLASTIC COVER and that THE INTAKE MANIFOLD IS MADE OF PLASTIC. What the?

Patched.

 

There should be two gaskets, well three really if you count the top cap. Most of us will also take the crossover pipe off to ease with the short hose coming out of the front of the thermostat. You will need the two gaskets that go on the crossover pipe.
Sorry you are have so much trouble.
BRG, this is the earlier 2000 one.


Wayne

 

Thanks for all the replies. I wasn't having too hard a time, though I thought I was experienced enough to not be making these rookie mistakes!

I missed the gasket for the top cap- thanks for the reminder.

 

also when replacing the stat housing i used hex bolts for the rear bolts to make future removal easier in the future... others have cut a slot on the top of the bolts for a screw driver blade to fit into . the stat is very easy to put in backwards .