Hello,
so I got the first Jaguar of my life 2 days ago. I did 240miles.
I Am located in California bay area. I found the car northern near Sacramento. When I picked it up the temperature outside was very high, 106F. Driving back to the Bay Area the temperature gauge on the dash would range from 90C cruising at 60mph to 95C on steep climb over the hills.
When I reached the Bay Area the outside temperature was around 75F and then the gauge stabilized around 80C. Anyway it was so hot that also my iPhone died...
Usually the temperature gauge range now is between 75/78C
and 88/91C depending if I drive in the northern and east Bay Area or in the southern bay (San Jose) where the outside temperature can be even 104C or higher.
Anyway I noticed that the radiator fan is always spinning, even at low temperatures like 70C. As soon as I have a cold start up and the water temperature is very low, the fan is always working regardless of this.
Do I have to be worried about these temperatures ? The water pump was replaced one year ago.
Do you think I should install a different thermostat which opens at lower temperature ?
What is the temperature limit that should never be reached ?
By the way, standing in the traffic for several minutes (10 or 15) has as a consequence the gauge temperature to go up to 90C.

thank you

Rick

 

"Normal" and desired temperature is 88-90ºC.

You should have an 88ºC thermostat. If so, the engine should obviously run at least that temperature. It sounds like you're engine is presently running a bit too cool at times, @ 75-78ºC

Climbing to 95º during a long pull in a hot day is no cause for alarm

Fans....

Are you referring to the belt driven fan? Or the smaller electric fan? The belt driven fan will spin whenever the engine is running. The electric fan is set to come on at about 94ºC. It shouldn't be running all the time.

Cheers
DD

 

thanks.
Well I Am referring to the yellowish fan you can see in the left side of picture in the front part of the engine
http://www.wmsbrg.com/british/87vdp/lengbay.jpg
it is always running even if the engine is just started.

 

Congrats on the Jag. You might want to look very closely at your yellow radiator fan. If you see hairline cracks it it, then put in a new one. It's ready to explode under the hood. Not good.

 

Will do that Michael, thanks

 

my 1984 has had and still has a yellow fan and it has not exploded since I purchased the car in 1989. Leave it alone unless it is obviously cracking. I'll let you all know when mine explodes.

check the coolant level when the engine is cold, remove the cap at the brown expansion tank and make sure it is full, up to the bottom of the filler neck.

there is an auxiliary electric fan under the front bumper, in front of the car. It should come on automatically when the gauge enters the red zone of the dash gauge, if not earlier.

if it doesn't come on, check the fuse in the 5-fuse fusebox located in front of the coolant expansion tank. Roll it in place, the brass contacts holding the fuse tend to oxidize and the fuse loses contact.

(the other 4 fuses are for each low beam and high beam headlights). If one of the headlights does not come on, check those fuses by rolling them in place, same principle as for the auxiliary fan fuse.

there is a mod (modification) for the auxiliary fan in which you can rewire it to run continuously whenever the Air switch by the radio is in any of the ON positions, (Auto, Low, High).

however, it is noisy, though it makes the XJ sound like a Maserati at red lights. BUT, you can mod the mod by adding a on-off switch so you can turn the auxiliary fan on or off whenever you want from the comfort of the driver's seat.

the question is WHERE to place a on-off switch inside the car. That is the question. Anything that looks like an added on-off switch, always looks tacky, so I've never done it. A miniature push-push switch would be about the only type of switch that I would use. Then comes the rating of the switch so it doesn't melt, and I haven't got time to calculate that kind of stuff.

 

That the engine driven fan. It turns whenever the engine is running, hot or cold

Cheers
DD

 

thank you!

 

Kudos!!!


That engine bay is well tended. And, all seems decent. It performed well as to temp's during our hot spell.


As Doug says, thermostats are kind alike on/off switches. They neither create not cool temperature. They merely regulate it.


Enjoy your find.


Carl