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MG MGB GT V8 Factory Originals Technical - Oil Cooler: to have or have not?

Primarily due to lack of space I'm considering losing my oil cooler. It's hooked up via a thermostat and doesn't seem to flow oil through the cooler except in standing traffic.

DOes anyone have any views/experience regarding this. I know the RV8 doesn't have one. Did they build the Supersports with one?


Yes, the supersports has an underslung oil cooler.
Geoff King

I've decided to ditch the oil pressure gauge and replace it with a dual oil pressure/oil temperature gauge - capillary. This requires a little work on the sump - very easy - but I have one on my Landrover and it provides very interesting information. Tom Shepherd in his Vehicle Dependent Expedition Guide has a fascinating and very readable chapter on oil, what's in it and how it works. It will change the way you think about oil. (It made me a much more interesting person and I have a girl-friend now).
I would have thought that an oil temp. gauge would be a useful intial stage in deciding whether or not to get rid of the oil cooler.

From what I gather (and I've done some gathering on this issue): (i) if you can lose your oil cooler without drastically affecting oil temp, so much the better; and/or (ii) if you use synthetic oil, it is much, much less temp-sensitive than regular oil and it can run quite a bit hotter.

Hope I gathered correctly, as that is what I've done!


I agree with Harry on ditching oil cooler as it normally just gets in way of airflow to rad, and if only being used in standing traffic no airflow, although a few pints of additional cool oil in system. The oil is getting rid of heat from the engine so if engine runs warm you may need the oil cooler just to help water system. You can get temp strips and if you can disconnect cooler take some readings before making final choice.


The coolant in your radiator is what cools the block and the heads, but the oil is what cools the internal parts of the engine. The oil cooler helps get rid of that heat. Like you, I use a thermostat on my cooler so the oil temperature can be kept reasonably constant. It also shortens the warm-up period and thus helps to reduce wear. Both the Rover V8 and performance-enhanced B Series engines have well-deserved reputations for running hot, especially when driven hard, so an oil cooler is a good idea in terms of getting rid of the heat. In easy driving on a cool day it probably isn't an absolute necessity. However, I consider the oil cooler to be like insurance, a d*mn good thing to have when things get tough.
Steve S.


If I recollect correctly your water is running at 140F.

Checking on Mocal site the oil thermostat will open at 176F as this is minimum temp required to evaporate and dispel contamination substances. Your water temp is the reason why your oil cooler is not being used.

Although no confirmation of correct water optimum temp, I'm convinced should be minimum 182F (water thermostat) which will bring your oil cooler into play, so may be better to defer your decision.


Whilst the rad is away being used as a partial template for an aluminium one, I'll take the opportunity to strip the cooling system back as far as I can and rebuild it. Check the water thermostat etc. If the new rad will fit with the oil cooler and oil thermostat in place then problem solved. Rad won't be ready for 3 weeks so plenty of head scratching time before it arrives.


Another possibility is to have the oil cooler built into the lower radiator tank. I have never seen one like this, but have read about it in Summitís catalog. They claim it cools the oil better. Cooling the oil this way reheats the coolant, but putting a conventional oil cooler upstream of the radiator preheats the air used to cool the radiator. Either way, is the overall temperature reduction worth having an oil cooler? The answer must lie in what Steve S. said about cooling the internal parts vs. the area around the cylinders and heads.

The other point is the water-cooled system has a thermostat to allow the coolant to warm up to the idea temperature as fast as possible, where as most oil coolers donít. In cold weather the oil will be too cold and not lubricate as well. Balance that against viscosity breakdown when oil gets too hot.
George Champion

Is anybody making a finned aluminum pan yet? Seems that would be most helpful.
Jim Blackwood

This thread was discussed between 09/07/2001 and 11/07/2001

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