The other day I was driving my XJS and I noticed a smell coming from the hood of the car. The next thing was my antifreeze light came on and I suspected I might have a leak after seeing a lot of smoke going from the underhood. I popped the hood and noticed their was antifreeze sprayed over the under part of the hood. I filled it with antifreeze and started it up again (needless to say I know have a lake of it on my driveway;) But this time I know where its coming from its running from the hose all the way to the thermostat and it sprays out at that connection somewhere. The spot I am talking about is the Thermostat hose on the drivers side of the car and there is a spot where a bolt or connector is and it appears to be coming from that spot. I fear the thermostat may be broken open or closed either way not good. So if anyone can help me in my predicement I would be most greatfull thanks for youre help.

Alec
1988 Jaguar XJS
Super Leaper
V12, Coupe

Submitted by north_sider_@h… on Sun, 02/29/2004 - 17:52

Okay my problem has become worse. Now the car wonÆt start either and I replaced the battery. I turn it on and the engine sounds like it wants to start but dosnt turn over I'm pretty sure it "was" flooded but still dosnt want to turn over I'm afraid I might have fowoled out the sparkplugs a little to much.. Any advice is great.

Alec

Submitted by silver007@shaw.ca on Thu, 02/19/2004 - 22:58

Hi Alec,
when you have found the leak, buy a set of NEVER FAIL THERMOSTATS. These thermostats never fail closed, so you cannot overheat the V12 because of stuck closed thermostat, if there is no jiggle pins in these stats just drill a one eighth inch hole and position in engine with hole at uppermost area, These stats are installed in "Silver "

Art Dickenson.
1983 XJS GT \"Silver\"""

Submitted by NE52-32043 on Thu, 02/19/2004 - 17:16

Alec,

There is a gasket between the thermostat housing and the manifold. It sounds like the gasket let go. Although the thermostat might not be working, it wouldn't cause what you're talking about. I'd suggest that you remove the housing, check the thermostat and replace if it is not in good working order -- (do you know how to check it by suspending it in a pot of water on the stove?).

You should also check all of your hoses and replace them if they are at all questionable. The one "forgotten" hose is the bottom, return hose. That one tends to collapse when old and weak, causing the flow of water through the system to be restricted. When changing hoses, it is preferable to use new hose clamps. Don't reuse the old ones, if possible.

Parts are readily available from "the usual suspects." Try Coventry West (NAYYY, just a former customer). I got a fair number of XJS parts from them when I owned one. Get the right parts. The termostats MUST have the by-pass cutoff or you'll have problems. The hose kits from the usual suspects contain the correct hoses with the proper bends.

And when you refill the radiator, use a 50/50 mix of antifreeze and distilled water, and add a bottle of Redline Water Wetter (it will help with the cooling). Also, consider flushing the block and radiator before you refill. And whatever you do, DO NOT PUT IN BARS LEAKS!!!

Steve Weinstein, JTC-NJ
'72 E-type 2+2
'70 XKE FHC
Former '89 XJS Coupe owner