Ideal oil temperatures, and engines that might be operating far below the ideal?

SW Lee and his Father

SW Lee left, And Lee’s Father, a master of ‘Kiss’.











Above left are SW Lee, a DIYer in Malaysia and his Father on the right who spent his life maintaining diesel power plants during his working days. Lee said his career started when he got the only diesel to work on when he was just 16, no one else wanted it, and that lead to his better understanding of all things diesel.

Sometimes we forget where our knowledge came from, but I’ll always remember something that was passed on to me by Lee’s father as per the building of direct drive equipment. Mr. Lee would build a frame where the motor mounts were left loose till couplings were well aligned,  then precision holes were drilled and shoulder bolts used to put it all together, this allows a quick disassembly to replace a Lovejoy spider or similar, and have it all fall back into realignment without shims and tedious time-consuming checks.

The nature of Lister clones is for the lube oil to run very cool, and very cool oil is nowhere near as slippery as a more ideal temperature of 180F.  Many if not most people think that it’s the coolant that should be warm before you really work your engine hard, but some engine controllers don’t allow you to make use of full power till the oil temp is in-band as well.

After years of studying stationary power and the Listers, my favorite cooling system is a modified thermal siphon system with a lot of headroom in the top of the tank (above of where the fitting returns to the top of the cylinder) where the system can go into hopper mode if necessary. A long piece of metal pipe from the hopper to the atmosphere acts as a condenser, and unless all is grossly undersized, you won’t have to add coolant. Antifreeze is what I add, and rainwater is always a good idea.

In a previous post, I mentioned that modern lube oil has none of the protection in it that the design engineers expected when they designed in the clearances, valve train pressures, and the materials used. Gone are ZDDP (zinc), and other antiwear agents that mitigate wear. So we might have multiple less than ideal situations working to shorten the life of our beloved machines?

Here’s a few items I’d consider checking, make sure the dipper is creating an adequate splash in the cylinder,  push the coolant to a higher temp, do not run at 160F, do some thinking before you use bleed water cooling, Make sure the protections in your oil more closely matches what the designers of your engine thought would be used in it. Another thing I like is an engine shed, if you will be operating in real cold weather, this can certainly help.

Taking the heat out of the exhaust can lead to all kinds of issues as the condensed gases can be very corrosive, so trying to recover this heat in the exhaust is the last thing I’d try. From the exhaust, you immediately pipe downward, after that you might go on the horizontal to exit a shed wall.  A lot of damage can be done when condensed gasses are trapped right at the exhaust valve, I have seen some valves that are heavily and deeply pitted by this situation. Go down, and don’t forget there are 45 degree pipe fittings to be found.

Some people might have the skills to make a jacket for the sump area and cylinder jacket. It might really help in running the more ideal oil temperature?

In closing Oils have indeed changed, Lister 6/1s have not.


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