I've mentioned this before, I think, but back in the days of short blocks supplied by big engine rebuilding concerns there was a product they ran through the lubrication system as a last step before packaging after they bench 'motored' the short block (with its lubrication system externally pressurised) to do a final check on the cylinder bore lube jet orientation, gallery plug leakage, excessive oil clearances etc. It went in as an approximately SAE15 but 'hardened' to a greasy film and acted as a long term preservative on all the internal parts. Like a slightly thinner consistency cosmoline I guess. The recommendation was to just wipe off any excess when fitting the short block as the product would disperse in the running in oil with no ill effect. I've also heard of it being put in the sump of an complete engine (after the actual oil was drained) and the engine being idled for a few minutes before the engine was put into storage. I want to say it was Shell 'Ensis', but I'm not 100% sure that was the correct name.
There's at least one automotive machinist contributor on here, I'm sure they'll be able to name the product?
There's at least one automotive machinist contributor on here, I'm sure they'll be able to name the product?