Oil taking longer to heat up than water.

[Mabbs]

Could someone please help me understand how oil takes longer to warm through? Yet water can then help cool the oil? If the water is heating up more quickly then what purpose does it serve?

 

I once believed that the oil must heat more quickly, due to it's proximity to combustion/compression and the fact that it is thrashed by moving parts. I then thought the water, slightly further removed and obviously running through a heat exchanger, did the cooling.

 

I'd be interested to get a better understanding if anyone has the time.

 

ATB

 

Chris

[Jonathan Kay]

Think of the warming-up phase and the steady state as being two different things. Here's a thought experiment that might help. You could always slow the warming of the oil by bolting on another well-insulated reservoir of oil. But that wouldn't affect anything in the steady state.

 

Jonathan

 

Edited by - Jonathan Kay on 3 Apr 2013 15:24:07

[Stationary M25 Traveller]

The waterways in the head are larger and designed to take the heat away to a nice cooling radiator.

 

At this time of year, my 1.8 k-series (with recent cooling system mod) warms the water up to 80C within 3 miles. The oil takes about 15 miles to reach 70C.

[Johnty Lyons]

The heat of the water will have no effect on oil temp FWIW on a busy track day you oil could get well over 150 and in some cases up to nearly 200.

Those of us running dry sumps where oil capacity could be over 7 ltrs quite often fit a laminova ( oil water heat exchanger) this can when oil is cold assist with more rapid warm up and later on works in reverse dumping excess oil heat into the water where it id dissipated by the Rad.

[Mabbs]

Thanks gents, that's a big help!