Sorry, I made a typo, I meant to write Oil Cooler, not Oil Filter.
The Oil Filter remains in circuit at all times. (40 lashings to me).
If you ever recondition your engine if it's been fitted with an Oil Cooler, it is proper practice to bin the Oil Cooler and fit a new one that has had bungs fitted while in storage. The passage ways through them are 'fine' and cannot be cleaned properly and even if cleaned, cannot be checked. Remember, these are on the dirty oil side of the Filter.
I did run one (13 row) on the wife's Moke for about a year, along with an Oil Temp gauge. The Mokes are fitted with a pretty full on sump guard and there is no ventilation what so ever over the sump. The way these cars get driven (well, the way we drive them!), is very harsh especially with respect to Oil and Oil temps. It's not uncommon on an extended trip (7 000 - 10 000 km) for the Mokes to tip the scales at around the 1 200 kg fully laden. We drive them at speeds of around 100 - 115 km (3 900 - 4 100 RPM) for many days - 6 - 10 hours at a stretch - and then also spend around 7 - 14 days pretty much in 1st, 2nd and occasionally 3rd gears, so lots of load and very little air flow. Cooling systems are pushed hard as ambient temps can vary from 00 overnight (though we don't drive at night, it's not unusual to experience these temps for an hour or so first thing in the morning) to 400 during the day and we have even had a few days that have peaked at 530. Due to the rough terrain, the Drivetrains (including the gearbox) to cop a fair bit of 'impact' loading too. I would suggest that they Gearboxes (and Oil) experience harsher conditions and treatment that any race car.
So, what I found was that the Oil Temp very closely followed the Coolant Temp under just about all conditions (except at the long high speed runs), though it did lag it by 20 - 30 minutes (ie it took longer for the Oil to heat up when the Coolant did but took didn't take long for the Oil to cool to that of the Coolant), I don't recall ever seeing the Oil temp go hotter than about 150 hotter than the Coolant, but for 99.99% of the time, it was well within 50 of the Coolant. On the longer high speed runs, the Oil just ran too cool - from 60 to 720 and so after a few trip, I made a 'blind' to slip over the Oil Cooler.
After a year, the Oil Cooler began to leak (can't understand why), so I by-passed it. Oil Temps remained the similar as before only the warm up temp happen quicker, the cool down time took a bit longer and on the longer runs, the Oil Temp sat around the 85 - 900 mark, much happier.
<EDIT: I forget what the correct term is, but in regards to Oil, it is not nearly as thermally conductive as coolant (or indeed the Air). What I am getting at with this is for the same BTUs of heat, it will take longer to heat Oil and Coolant (or the Air) and likewise it takes longer to get that heat out of the Oil than would be the case with Coolant.
With that in mind, compare the area of the Coolant Heat Exchanger (Radiator) to that for the Oil and also to further put this in perspective, there is around 3 litres of of Coolant in the Cooling System, and we have around 5 litres of Oil, in the Lub System. On top of this, we also have a fan to force Air through the Coolant Heat Exchanger >
Edited by Moke Spider, 24 June 2015 - 10:12 PM.
