Should I be worried?

[paulc]

On the M23 on Sunday night, doing 70mph up a long incline - loaded up with heavy scuba gear - levelled off and the Surf started getting hot - got to about 3/4 of the way over on the gauge, so I pulled over and switched off, left it for a while, expandion bottle bubbling away, topped up with cold water via the rad cap thing (a bit of steam and water shot out).

Left it another 15 mins of so then carried on back to St Albans on horrible M25 stop/start 20-30mph for about 2 hours due to heavy traffic and the needle was bang on where it normally is (just under 1/2 way).

I going to give it a flush and coolant change at the weekend, but am a bit concerned given all the head trouble you hear about, and was wondering if it's sign the heads on the way out or just the stress of 70mph up a hill loaded up?

I had flushed and changed the themostat about 3 months ago.

Any views?

[andy]

What about a new pressure cap, that could be the reason.

[Surfin' Jock]

Don't panic....but....

Last time I was carrying a load of flooring and nipping along quite nicely when the engine overheated, caused a hole in the radiator.
New radiator fitted, first day back was stopping at lights and engulfed in clouds of white smoke. Took back to the garage and found that head was indeed knackered.
Try to get a diesel specialist to check over head for cracking of possible without removing.
It seems to be the curse of the 2.4 stiking again.

Good luck

[kitesurf_phil]

My Surfs temp guage has only gone over half way once. That was hauling the caravan up a big hill in Devon (can't remember the name of the hill now). I used my experience of some of the real doggy cars I had owned previously and turned the front and rear heaters full up. With the fans on full the temp crept down before we reached the summit of the hill.

If the engine has over heated, then it will dump the pressurised water into the coolant bottle because the overheating has made it go over pressure.

I was told that the worst thing you can do when the temp guage shoots up, especially under load, is to stop and immediately kill the engine because it stops the circulation of the coolant and kills the fans.

[paulc]

Thanks for responses guys, should have added - I did change the cap a couple months back, and had the heater on full all the way home. Think it might just be the stress of the hill and load. I've got an AA warrenty on it so if the head does go I think it will be cover by that.

[stara]

a long incline with heavy load will put the engine under load at lowish speeds at this point the viscous fan would engage, (as it does on mine when i drive up glyn neath bank with a truck full of drums and amps). bizarrely It is often often often overlooked, and rarely even warrants a mention yet is a crucial part of the cooling system, the 2.4 head is fragile, and overheating can cause cracking on any head, keep it cool, check your fan.

[paulc]

Thanks Stara, how do you go about checking the fan is working effectively?

[stevo]

viscous fan

a long incline with heavy load will put the engine under load at lowish speeds at this point the viscous fan would engage, (as it does on mine when i drive up glyn neath bank with a truck full of drums and amps). bizarrely It is often often often overlooked, and rarely even warrants a mention yet is a crucial part of the cooling system, the 2.4 head is fragile, and overheating can cause cracking on any head, keep it cool, check your fan.

The viscous fan coupling has been discussed many times, there are several posts showing how to check and overhaul the fan coupling.
Cheers Steve.