to change oil or not????

[landrovered]

"Rust inside an assembled engine or transmission can occur any time the oil is allowed to drain off a component due to infrequent use. Engines which are operated daily or weekly seldom encounter this problem, but many street rods, muscle cars, and race cars are often stored for several months without being turned over or fired up. This is a recipe for rusting problems.

Water and low temperatures significantly increase the propensity to rust. Engines fired up infrequently generate a tremendous amount of condensation. If the engine isn’t allowed to completely warm up, this condensation remains inside the engine. (Water will not burn off until the internal engine temperature (oil temperature) reaches 212 degrees F.) This water will then attack any surface which isn’t adequately protected by either an oil film or a vapor phase rust inhibitor ( new tools which often contain a packet of vapor phase rust inhibitor to prevent rusting in shipping and storage)."

Driven Racing Oil Website.

It would appear we have a consensus on water and fuel in the oil as being the problem. As I stated correctly, running the engine periodically to temperature is key in preventing rust.

[JFP in PA]

Originally Posted by landrovered

[I
As I stated correctly, running the engine periodically to temperature is key in preventing rust.

Actually, because such short runs only serve to accelerate the contamination of the oil, entrain more air, and heat the oil up; this only serves to accelerate the oxidation chain I described above, worsening the formation of the organic acids.

We store several high end cars for select clients in a secure environmentally controlled storage facility. None of the car are started for the entire storage period. Over the 30 or so years we have offered this service, UOA's taken in the spring have shown no degradation of the oil, and bore scope cameras have shown no apparent rust formation of any rust or corrosion.

[PatM]

I changed the oil today and am sending a sample to Blackstone labs.
I have mentioned my concerns about acid buildup and we will see what they say.
I believe that I will change every 6 months no matter what they say...less than 5000 miles. One of the problems with where I live is winters can be mild or not and with climate change. who knows???? I might put 100 miles a week or maybe 0 a month
Better to be safe than sorry. I surly can't afford an engine......
Thanks again for the input