Using diesel fuel in a cleaning process and its potential effect on rubber seals

General Discussion
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I found something online with regards to diesel fuel and rubber.

“Rubber” in a the last 50+ years or so is a meaningless generic term. There are as many types of “rubber” as there are plastics, or woods in the forest. Some “rubber” quite happily seals aircraft fuel tanks…or is so stable it is sent into outer space…or is so inert it is used for medical implants. But these are all chemically as different as chalk & cheese. Their only similarity is that if you stretch them, they snap back into place (usually!)

Natural rubber (from trees or its synthetic equivalent) has no fuel / oil resistance and is not often used nowadays. Nitrile, Neoprene, fluorocarbon and other types do. Many modern synthetic rubbers will not be harmed by the the occasional splash with fuel so long as it’s transient. Many are quite happy in hot engine oil for extended periods. Generally what happens is the rubber swells and this weakens it. If the swelling is reversed (the fluid dries out) then often there is no permanent damage."

So it all boils down to which compounds are used in our engines. Though if diesel fuel is used for very short periods mixed in with engine oil then would it be an issue anyway ? I would imagine diesel engines have injectors have rubber o-rings so I wonder if similar compounds are used inside petrol engines ?

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2

I use sea foam engine treatment, it does the same thing as diesel but is made with stuff safe for engine seals. I like to add about 8 oz to the engine oil and run the car for about 30 minutes before changing the oil. Helps a lot with lifter tick, I will sometimes add a little mid oil change if lifters are being annoying but I try not to run the car very hard at all since I herd it makes the oil not handle heat as well. Also royal purple helps lifter tick too. 50 bucks for oil is a lot but its still less than 5 grand for a new engine.

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Engine oil gets regularly contaminated with fuel every time someone fits a catch can wrongly and disables the PCV system. Same goes for diesel engines that use seals in the injector pumps. It’s a total nothing. A non issue.

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