Thread: Old girl got hot

Maybe the thermostat is sneaking closed after being open for a while.

What road speeds are you doing when this occurred? Any recent work on the cooling system? How many klms?

How long were you stopped for? Long enough for thermostat to cool down enough to close?

Dave

Old girl has done 210000kms and had a new radiator put in before I bought her at about 180k.

Seems to be happening more frequently now, startup temp can vary between 60 after a long break to 80 after 10 mins. She will warm up to about 86 and then will start to climb in temp fairly quickly whether I'm cruising at 60ks or pushing harder. Once I pull over and shut down I can then restart and at idle everything will cool down to low 80's before taking off and having a stable 86-88 and running smoothly. Almost like a shutdown resets something in the cooling system. It's got me stumped.

Cheers,

Rob 99 disco td5

Well I have now had two trouble free days of motoring around coffs with temps stable at mid to high 80s. Seems as though the problem only occurs after long runs at high speeds (500+Kms at avg speed of 110).
I'm thinking maybe thermostat played up after such a long run at operating temp or perhaps expansion tank cap not set at correct pressure and over pressuring system as pressure=heat.

Going to get Coffs 4x4 to do a coolant system pressure check and then as a precaution will ask them to replace thermo, tank cap and do a full flush/coolant change tomorrow.

Any thing else I should be pointing towards? No sign of coolant leaks but tht doesn't seem to mean much from what I've read.

Heading back to geelong in a few days so I want to make sure she's up for those long k's again.

Cheers,

Rob 99 disco td5

What about the viscous fan?

When you pulled over & the temp was high,could you here the fan roaring?

Think you might be on the money with the viscous fan. Had thermostat and coolant replaced and she drove the first 800kms beautifully and stopped for the night. Today after about 200kms she got warm (95c) getting up a long steep hill and then we hit 40km/h roadworks on the peak which she then got over 100c and I pulled over and shut down. Restarted and let her cool at idle and off we went. All good til I had to do a u turn and off she went again.
When I got home I lifted the bonnet and it was very quiet even though the coolant temp was 93c. I would think the fan should be roaring at this temp right? I was able to slow the fan almost to a stop at idle with a sheet of rolled up newspaper. So viscous coupling stuffed I would think.
Any other tests to try before I replace it?

What's a new one worth? Easy to do myself or get a pro? I'm fairly handy with spanners but don't have a full workshop at my disposal.

Cheers,

Rob 99 disco td5