Well, it's almost time for Mr. J Junior to come out of hibernation; in the past couple of seasons I've dealt with secondary tensioners, ABS Module cold solder joints, and the infamous 'green shower'. This spring's target is to replace the thermostat and housing, as I'm pretty sure mine is the plastic version. It's kinda hard to tell for sure from tapping it, but I want to replace the thermostat, and I don't want the car 'down' if my guess on the housing is correct (the Dealer is at least an hour away). Is the improved (metal) housing part # different from the original? Any pointers or suggestions?

Thanks, People!

 

The plastic housings are black, and the replacement aluminum ones are silver bare metal unless it's been painted by the installer.

 

Right on on the color. Purchased mine from XKS Unlimited. Any competent DIYer or mechanic can install. Do the thermostat and hoses at the same time. You have to disconnect one end anyways.

 

Before you fit the aluminium housing check that the top cap(with the inset hex) seals properly - I did mine a couple of weeks ago, didn't check and only found out once fitted that it was machined about 2mm out - leaked badly. I had to make up a thicker rubber gasket plus use the O ring supplied to get it to seal. There are other threads on here about the poor quality of some of these aluminium replacements.
BTW I found it impossible to remove the old housing even with a good crow foot wrench - ended up removing the inlet manifold which isn't too much of a job - replaced the two heater hoses underneath at the same time.

 

Carefully breaking off the old one works too, allows good access to the rear bolts. I used visegrips and broke it up from the top down.

 

Jaguar black plastic OE on the left and aluminium aftermarket replacement on the right:



Buy a crows foot wrench to access the rear bolts before you start. Breaking the original housing leaves you no way back if things go wrong. There was a report here recently of an aftermarket housing having the bolt holes drilled incorrectly and it wouldn't fit.

Graham

 

Yes, it is usually not an upgrade but a new problem. Most shops I've talked to do not recommend these as they leak more often than the stock version. I would avoid this switch.

 

I broke my housing up to remove it. It's not my only car and if laid up for a few days no big deal. Bought the aluminum housing from Welsh, thermostat included, and replaced the rear bolts with socket head screws tightened with ball end hex driver. Replace that short connecting hose while you're at it.

 

Thanks, Guys. I'll order the parts, and tackle the job next rainy day. Maybe one of those peat-flavoured bevvies afterwards!

 

RJ237 has a good idea in using the socket head screws rather than the originals. I typically take the rear bolts and cut a slot into the heads so I can easily drive them in with a thin screwdriver before tightening them. I have probably replaced a dozen of these with the aluminum type, and only had one that was defective. The quality isn't the "finest", but they do work!

 

Just a foot note make sure that the thermostat is set correctly. There is a hole on the thermo, make sure that it is pointing in the up position. It is designed to allow the air to get out of the system. When I replaced mine GGG (Graham had a great pic of the of the radiator drain plug and the position of the thermo) Jim

 

That's an important point. I checked the one I got from Welsh before I installed it and found that the thermostat could only fit if the jiggle valve was up and the spring in the right direction.

 

You might also consider that the bright aluminum is going to look a little out of place at the top front of an otherwise all black engine. I would suggest that you paint it black to match before installation. After all, the plastic housing was just painted plastic.

Breaking up the old plastic housing eliminates most of the access problems. You really don't want to remove the intake manifold unless the hoses underneath need work.

 

I was changing mine because the previously fitted aftermarket aluminium one was leaking - of course that also meant that the option of breaking off the old one to remove the back bolts was not available to me.

 

And on the thermostat pin, I believe Brutal said he removed them before installing the thermostat. I did (more of a small ball than a pin on mine) and positioned the hole at 12:00 o'clock. Seems to work fine.