P38Penguin

Active Member
Hi guys,

I've had a search but not really come up with a definitive answer. What is considered the normal operating temperature of the 4.6 gems? From what I've read it seems to be mid 90's ish.
According to nanocom, mine is running at around 98-100 which seems a bit too high for my liking. In the last year I've replaced the thermostat, waterpump and radiator (3 times but thats another story lol). It's never overheated at all but when you park up it is a bit toasty. Done the newspaper trick on the fan and it shreds it.
Am I over-reacting?
In the next month or so I'm going to be stripping it down to replace the rocker cover gaskets and replace the lpg pipes. Anything else I could do while I'm there?

Thanks for any advice
 
What's the thermometer on the dash showing? Mid-way?
Does the temp guage show a real life reading? I always thought the needle stayed at 12 o'clock under varied temps unless the engine overheats, then it hits the red pretty quickly?
 
Does the temp guage show a real life reading? I always thought the needle stayed at 12 o'clock under varied temps unless the engine overheats, then it hits the red pretty quickly?

Seems OK on my diesel. Not sure about the petrol.
 
Bang on half way, doesn't stray from there

If it does not move from mid point it is fine. Engine temp will vary depending on ambient air temp and engine load. Early petrol stats opened at 88 degrees, later 99 and on 85 degrees plus or minus 5 degrees. Boiling point is 100C or 212F at atmospheric pressure. With a 15 pound cap fitted, no leaks to reduce pressure, and 50% anti freeze, boiling point is 129C or 265F.
 
LPG is a hotter running fuel, but your cooling system should easily cope, my V8 Discovery runs at the same temperature, LPG or petrol, just to to the right of centre on the gauge.

Peter
 
Mine is very similar. I run LPG. Needle is at 12 o'clock all the time (once warmed up) no matter if I'm driving gently along in February, or towing up a hill at speed in August.
Always feels a bit toasty when you stop. But nothing's ever melted or started burning yet!
I overheated once when my HG was failing. Needle went from 12 noon to the red bit, with the flashing red lamp in about 20 secs. I actually saw it moving, and pulled over to stop the engine.

If you're taking the rocker covers off, you might want to clean them up underneith. Mine always gets a load of oily gunk stuck to the underside that I like to clean off. Not sure if it makes any difference, but apparently it helps the V8 "breathe" more easily....
 
Yes, taking the rocker cover internal oil baffles out only involves 8 self tappers, and there is usually plenty of hard deposits behind.

Peter
 
Make no mistake these run hot 100c plus when stood in warm weather after a run with air con etc. I've no idea why they run so hot.. some say emmisions? Open the bonnet and the heat is like a wave. It leads to lots of things going crispy(pipes wires etc) it means the system is under tremendous pressure. But it is correct.
My xjs similar vintage same ems runs remarkably cool 80 or so.
Just keep the system up to standard and don't worry!
 
Mines running between 85/87 mixed driving real time temp from the heads up display I have fitted iv been keeping an eye on it after a mystery leak which I think iv fixed.
 
Thanks for all the feedback guys, I know the cooling system is critical so it's reassuring. Found a drop of coolant under the brake pedal on the rubber mat so suspect the matrix o-rings are starting to leak, will have to have a closer look.
Yes, taking the rocker cover internal oil baffles out only involves 8 self tappers, and there is usually plenty of hard deposits behind.

Peter
I tried to to change the oil seperator but as it's so small it snapped in half so will do that, plus a darn good clean won't do it any harm.
 

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