As many people here know and post about, one of the biggest issues with XK/XKR's is overheating. I now have an OBD monitor so I've been monitoring my car for the past couple of months. When it's just cruising on the highway it's usually between about 184 and 188°F. In stop and go traffic it can get all the way up to about 204°F. I live up a steep hill that has stop signs at the very top it sometimes gets up to 210°. Today was rather warm here so I had the air conditioner on and when I got to the top of the hill it was 212°. Do these temperatures sound normal for the 5.0 XKR and at what temperature should I actually start to worry and turn the car off at?

Thanks in advance for your input,

Buddy

 

You're fine. Normal temps. Don't let it get much above 215 though, or for too long. Keep an eye on your fluid also.

 

Cool, thanks CeeJay. At what temperature is the warning light supposed to come on at?

 

Budster,

You are obviously aware of the 5.0L engine water pump failures, and your OBD temperature monitor is helpful. Another warning is the tell-tale aroma of anti-freeze. After you get out of your car, stand in front of your car and if you smell anti-freeze, open the hood and check the coolant reservoir. If it's not full, there's a leak. It may or may not be the water pump, but it needs to be diagnosed and fixed.

On hot days, after a drive I usually leave the hood fully open to let the hot air out when I park in my garage. Heat is the enemy of the rubber parts under the hood, including the foam liner inside the Engine Appearance Cover. Ask me how I know.

Stuart

 

The warning light comes on after your system is dry and everything exploded already.
Get Some Gauges! Use any kind you can find, but get some!!!

 

Wow, you guys worry about the simple stuff way more than me. I feel like this is helicopter parenting the car. I am old school, when I see steam coming out my hood I know my car is overheating. Up till then I don't worry about it.

 

Actually, I’ve owned Jaguars since 1995. I’ve never had a case of overheating. So I have no idea what we’re talking about here.

 

190 to 210 is normal and even over 210 in some instances is not a problem. If you see it going up I would turn off the engine at 240*F. Remember with a pressurized system and antifreeze the boiling point is considerable higher then 212*F. I think I recall that a 14lb system with 50/50 antifreeze will boil at around 250*F

 

Oh, for such issues.

Graham

 

Here's a trick from back in the day.

If your car starts to run too hot, turn the heater on full blast - maximum heat and fastest fan speed. The heater is a small radiator in the cooling system loop, so it should help bring the temperature down (assuming that you haven't lost too much coolant).

I don't have to tell you to roll down the windows.

 

I got myself one of these neat Auxiliary Display Units from forum member @Cabrio Bob - see his thread, here: https://www.jaguarforums.com/forum/x...cation-233044/.



My normal running temperature is between 90°C and 95°C (194° - 203°F). It is usually close to 90° and I have never seen it go higher than 95° in any circumstances, even when driving last year for extended periods at 100 mph in France where the OT was 40°C (104°F). My car is the 4.2 Supercharged engine though not the 5.0, and this may make a difference. I find that the addition of the ADU gives me greater peace of mind - as Cee Jay says, if you rely on the warning lights, you're probably too late.

 

I do have lower temperature thermostats available for 05-09 cars three-piece design. Also The new unit will not have the rubber surround which is the major failing point on our cars thermostats...

 

I am glad some of you haven't heard of or experienced any overheating issues. When I had my '06 XK8, it did overheat twice. The temperature meter went all the way to the top and it turned orange or red in the display.The first time I think they replaced the thermostat and then it happened again and I think they did a radiator housing and something else. The issue never returned. I actually really miss that car and wish I still had it. My 2017 F-type that I had for three years never had any over heating issues. I miss that one too I'm just trying to watch out and look for this.

While I don't have a device as cool as the modification from Cambria Bob I do have this little OBD II reader box which is what I was reading the temperatures from in my first post. I've only had my 2010 XKR convertible for about nine months and I'm slowly doing a bunch of little things that it needs and trying to watch the temperature.



OBD II reader

 

Hi, reading that there is much sensitivity about overheating, I wonder if anyone has considered or experience of using Evans waterless coolant which has a boiling point of 375F.
I am about to use it in my classic Lotus which frequently overheats but have no personal experience yet. Other Lotus club members are using it so far without issue.
It is required to completely remove all water/antifreeze from the system done by using a flushing liquid to dispel the last drops.
https://www.evanscoolant.com/how-it-...rless-coolant/
Any thoughts?
KenXJ8

 

Evans has been in my drag car for many years and I've never had a complaint. It does run cooler and doesn't blow out freeze plugs like normal coolant. Plus, can't run standard coolant on a track cuz Too Messy.

 

I have a 2011 XKR and had to do a water pump at 62k. I blew a heater hose last year $240. (78k miles) Had it towed in. then blew a hose under the plenum (had it towed in 79k miles) and told them to replace every hose they could find or reach. $2,000. I have a OBD now and it runs about 90C. But I am very careful. Both times the light came on and luckily I saw it and pulled over right away.

 

Probably true for old cast iron engines....however I believe our engines are aluminum.
I would think allowing a aluminum engine to overheat is very very bad. Stuff warps and no amount of machining will make it correct again.

 

One of the Forum members has put in the Evans coolant. Unfortunately I can't remember who it is. Suggest you enter Evans coolant in the search box and find him.

 

I had it done for me 3 months ago and am still seeing normal temps.

At the time I was having my SC, hoses and water pump done, so was going to loose coolant anyway.

There was an awful lot of prep as the previous owner or selling garage must have used non-standard coolant and it was quite gloopy

So, the process was:

• 5 x flushes with water
• 2 x jet-washes in between to blast out any crud
• drain down of system
• blow through with air line
• 13.8l of prep fluid (which I've kept 10l of for use on another car)
• 13.8l of supercool 180

Lucky I bought my fluid at less than half the normal price, bu it did cost me 2hrs labour £160/$200

Temps are no different (I have the ADU like Barnsie) but it seems to reach operating temp quicker, but I've not really driven in earnest due to lockdown, but have an 800 mile trip in July to have my transmission serviced, so will report back


I just wish Evans still did a sticker for the cap to remind the mechanic at service time not to top up coolant.