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Re: GU 4.2D - Engine Oil Cooler Options
Posted: 28 Jul 2011 17:46
by Ross
Clever Chaps indeed!!!
I just had a look at mine, and it appears to be exactly as per the diagram!
So now I`m sitting with an additional external cooler, and wondering whether its still worth while to fit it!
The rear crankcase oil seal wasn't actually hard and cracked (as we had expected it to be) when we removed it, it was just worn.

Re: GU 4.2D - Engine Oil Cooler Options
Posted: 29 Jul 2011 07:40
by Peter Connan
Ross looking at Pieter's result, I am sure it is still worth doing, as that will take some of the heat load out of your radiator.
Even on a Patrol, oils seals must wear out sooner or later? Your car is after all 14 years old?
Re: GU 4.2D - Engine Oil Cooler Options
Posted: 29 Jul 2011 18:50
by SRXy
It's old and all wear is from the surprise rear main seal passion that was had when the gearbox was out...lol.
If you've already sunk the cash I reckon it's a worthy exercise...surely it can't only improve the situation?
Re: GU 4.2D - Engine Oil Cooler Options
Posted: 30 Jul 2011 20:02
by ChristoSlang
Gents, what's a safe working temperature for engine oil?
I've monitored my 4.2 GL's engine oil (courtesy of my Madman EMS) for almost a year now and found that it's normally about 20 degrees below the coolant temperature. The highest has been a registered peak of 82 degrees. Is that fine, or should I worry?
I've also set the Madman's oil temp alarm to 90 degrees, mainly because it's sightly above the high water mark. Is that a good alarm point?
Re: GU 4.2D - Engine Oil Cooler Options
Posted: 31 Jul 2011 10:39
by David
Christo,
I think 90°C should be save. As far as I know mineral oils only start braking down from about 115°C which causes oxidation, which in turn forms deposits, varnish and increases wear. Obviously full synthetics will be higher - check this out:
http://www.mobiloil.com/USA-English/Mot ... _Oil_FAQs2 
I think a bigger problem with cheaper oils are the loss of viscosity as they heat up.