Well, if your oil gets dirty very quickly, the resulting sludge can reduce the flow of cooling oil under the pistons. Deposits under the piston skirts can also prevent heat dissipation.
This problem can be easily corrected. Simply run the engine at a fast idle with clean oil, treated with Flushing Oil Concentrate (FOC) for 30 minutes, and bring the entire oil wetted side of the engine back to pristine cleanliness. This removes carbon which insulates against heat transfer around piston rings, top lands & skirts. All sludge that constricts oil galleries, oil pumps and oil coolers is removed to allow the oil to do its important cooling job.
Another way to achieve additional cooling is by using a "water wetter", which provides faster, more efficient heat transfer. RMI-25 cooling system treatment does this...and a little more! It actually cleans and descales the entire cooling system, lubricate pumps and better preserves hoses, seals and O-rings. It can easily cool an overheating system by 10 deg C and more!!
For high engine load application, AW10 Antiwear is also recommended to reduce friction, wear and heat build up at highly loaded parts. AW10 is also useful for reducing operating temperature in transmissions, differentials, hydraulics, etc.
Datsun SD25 Diesel. For 4 years, Allan Dickson had been unable to solve an overheating problem. Despite flushing the cooling system, and fitting a larger radiator, it would always boil up the Toowoomba Range. After using FOC, it gets up the range at 70 kph (instead of 40-50 kph) without overheating. One of the functions of oil is to cool, and if flow is restricted, overheating results.
Landcruiser 1HZ Diesel (1994)
Hi Jimmy, I would like to say thank you for the extra bit of engine oil flush. I ran the flush thru the old girl with 9 litres of clean oil for 30 mins as directed. Well over 11 litres of black gunk came out. I was totally blown away by the sludge in the bottom of the Drain Pan. I've added a couple of pics for your website and feel free to use my above testimony of the result. I must say my Family were impressed and will more than likely be placing an order themselves.
Once again thanks Mate. (Evan Yates)
Nissan 4.2TD Patrol
(Peter Simms, HUMPTYDOO NT). Originally never ran hot, but in recent years it had become a problem. Peter had spent thousands of $$$ replacing radiators, clutch fan hubs, thermostats, chemical cleaning, etc, etc...all to no benefit, as nothing solved his overheating. In fact over the last 3 years, it just got worse & worse. The temp gauge would sit 3-4mm above the ½ way mark. Every time it ran hot, the air conditioner would cut out. After doing a web search, and finding reports of solving this problem, Peter finally tried the Flushing Oil Concentrate & Cleanpower pack. The overheating problem was immediately solved. Now at 110kph uphill, towing the quad bike trailer, and the temp stays cool. Peter also reports that after his first flush, the new oil was amber clean on the dipstick. Normally it went black straight away.
Nissan Patrol2.8L TD
I used the Flush to your instructions, and couldn't believe the sludge that came out!! The motor is now running a lot smoother and staying much cooler under heavy loads now, eg towing my 2 tonne horse float. Fuel consumption has also improved, but it is too early to confirm the figures yet. Les White, Heartland Real Estate GIN GIN.