The aux fan in my '95 6.0L V12 convertible only runs when it's leads are shorted together, and under no other circumstances. Does that definitively indicate a) the temp sensor switch is bad and b) the fuse and relay are good? If so I will replace the switch. If not I will check the fuse and relay.

 

Certainly the circuit relay etc is good. The switching mechanism needs looking at as you suggest.

 

The aux fan on my 1995 6.0 does not come on until after the temp needle is a little past the N on the temperature gauge. I checked it with a spot thermometer and the temperature is about 197 degrees. I believe this is normal. I wish I could find a sensor that would turn the fans on sooner.

 

Greg - Appreciate the quick response.

Looks like a switch replacement is in my near future...anything I should know about the process, seems, pretty straight forward?

 

RickE - My aux fan has never come on automatically, even with the AC on or the needle past the N on the temp gauge. Which prompted my investigation in the first place.

As far as cooler temp sensors/switches to turn the fan on sooner, see these links:

https://www.jaguarforums.com/forum/x...-4-0-a-247453/

https://www.jaguarforums.com/forum/x...h-aj16-219624/

I'd like to try the 6010.85 version but so far can only find the 6010.82 model.

 

The 6.0 uses a different temperature sensor/switch than the 4.0.

 

I was wondering about that. Back to searching for a correct replacement switch...

 

My recently acquired '95 XJS 6.0 V12 convertible seems to run hot once I get into local stop-and-go driving. On the highway, temp stays solidly between C and N. Generally won't get above the N mark unless its really heavy traffic, in which case it gets into the area between the N and the H. The very few times I could not avoid that situation, I put the car in Neutral and revved the engine to bring up fan rpms. I also pop the hood release to help hot air release, and always raise the hood once home to aid cooling.

Realized I've never seen/heard the auxiliary fan come on - however the fan blows up a storm with its leads jumpered. So it looks like the coolant temp sensor/switch is bad. While I am looking for a suitable (lower temp engaging) replacement, I wired up a manual switch to control the fan. So far in my local driving tests it has performed well to keep the temp gauge needle under N.

The car is originally from FL, purchased from a dealership two years ago and transported to NY. The NY owner rarely drove the car and did no maintenance beyond gas and maybe an oil change. Supposedly all relevant work was done prior to his purchase.

I brought it to a recommended local shop and had them go through it - replaced plugs, wires, cap, rotor, recharged the AC, replaced one bad injector. Belts, hoses, oil, oil filter and coolant were good, I topped off the coolant before a long trip a few weeks back, following the recommended procedure here, and also replaced the air filters with Wix (Mann) ones.

The main radiator fan clutch seems to be ok, based on the "flick" tests mentioned on this site.

To make sure all is running right, I'm thinking the following should be done:

• Flush the radiator and refill with new coolant
• Change out the thermostats
• Verify main fan clutch is ok

Anything else I should check?

My brakes are a bit squealy and I have a slight oil leak, so I'll address that soon as well.

 

I did a little research and it looks like the thread size for the EAC2510 6.0 switch and the DAC6794 4.0 switch is the same. If that's true, there are numerous switches you could use that have different temperature ranges. The thread size is M22 x 1.5. I have not verified this by checking the switch I currently have on the 6.0.

 

I was about to tell you this. I believe it’s the same. The OEM part may be different because the connectors are different, but if you are going to do what I did in some of those linked topics by creating your own switch, it’s a non-issue

good luck

 

My goal is to use the stock aux fan (which works fine) connected to a lower temperature coolant sensor/switch.

The (bad) switch currently in my car looks like this:




If the thread size is as we say, this one may do the trick:

https://us.gsparkplug.com/switches/t...5-095-070.html (86 °C to 81 °C)

For the price it's certainly worth a shot.

 

That is the correct thread size, 22 mm. The on temp (86) is the pretty well the same as the OEM fan switch on a 5.3 which is 85. OEM there was no gap between the on and off. If you want the fan on earlier, it might be worth finding an 81 or 82 on/off.

 

Agree with Greg.

All my 5.3 used the factory 85C switch.

I would flush that radiator, it is an unknown for sure.

New switch, and I would stay close to OE temps, and all will be fine.

Radiator restriction of 10% internal OR external on any V12 is trouble looking for some where to step off.

 

Really appreciate all the input. Trying to adhere to the "do it once, do it right, don't do it again" thing...

Is my understanding correct that for a 6.0L V12:

• Stock aux fan switch comes on at 92C and off at 82C?
• This Lucas switch comes on at 86C and off at 81C?

Greg - not sure what you mean by " OEM there was no gap between the on and off."

BTW, I reached out to V12 Performance yesterday, their site says they carry both an 82C/77C and 85C/80C switch. No response as yet.

 

Gets an F Rating on the BBB.

Check with old posts about people's success with doing business with this company.

 

Saw they had BBB complaints, and thought I had read some unfavorable reviews here.

Thanks, will stay away!