Preoiler & piston ring lubrication (engine guru question) ???

No piston & cylinder wall lubrication from a pre-oiler. My opinion is that a pre-oiler is a cure looking for a disease. What damage on previous engines was stopped by the subsequent installation of a pre-oiler? None that I know of. If you're talking about an engine in an emergency situation where you need to go from stop to full power immediately, yes, pre-oiler and preheat are very important. For the rest of us...what's the point?

Ken

Ken in your answer you described a an emergency situation however I don't have that but I have something that is a like paralell to it in my opinion. Consider this scenario: Winter in upper midwest, (Minnesota cold) Canada a few miles north. Snow deep. Temp last 5 days well below freezing, some nights below zero Vehicle not started 3 days due to roads not drivable anyway (oil well drained to sump practically dry engine) Note:Toyota start charecteristic is such that in this situation the engine flare to about 1800 rpm is common in my expierence when started when this cold. Time lag to get good oil pressure after start is XXX seconds Hit start & engine rattles loudly & oil pressure lag is noticeably or seems long & sounds like a diesel not a gas engine. Rattles comparable to diesel till oil pressure is up. Many seconds. I see this scenario many many days where I live. With my preoiler, I get 30 psi, Hit start & get instant oil pressure (no Lag) & engine does not rattle loudly like in the above example.Don't think I'm hurting much by having added a preoiler, on the contrary I feel better knowing that the engine had fresh oil, no time lag & very little rattling on start. A heated garage, oil heater, or a preoiler are the only answers to the brutal climate here &the first two mentioned are not possible where I'm at to help my vehicle out. I like the fact that the initial engine noises are much quieter & know that the engine has oil pressure sooner so start damage is minumial as compared to without preoiling. Besides the common wisdom seems to be that most wear is caused by starting a cold engine. Is this true or not? I felt obligated to bring my unlearnd opinion out but you have to decide whether there is any value to it or not.

PEACE

"Ken Shelton" wrote in message news: snipped-for-privacy@cablespeedwa.com...

I don't know anything about aftermarket preoilers, but in theory, I can't think of any thing other than positive effects. Common wisdom is to pre-oil newly built motors before the first start, so why would it not benefit other motors when they are cold? It may not hit every part of the motor that relies on oil, but it would likely hit main, rod, cam bearings and the upper end (valve train). I think I wish I had one.

The reason new engines are pre-lubed is because they have no oil in the engine oil passages. They also have no oil in the oil pump. You pre-lube the engine so that it will have oil to the entire engine when first started. Once an engine is started and the oil pump is working you have oil in all the passages in the engine when it is shut down. The oil does not drain out of the bearings and oil galleries when the engine is shut down so there is no need to pre-lube an engine before every start.

If an engine was really that starved for oil on each start do you think you would be able to get 300,000 miles out of an engine?

It may not hit every part of the motor that

Moving to a warmer climate may be another solution... :>))