Too Cold Oil Temperature??
Too Cold Oil Temperature??
(OP)
I've heard this several times that "Cold oil will cause engine damage"
I've yet to find any data to back this up though. The only specs I've found said that if temps were below 20F then warm the engine and oil up. With todays multiweight oils, I just can't think of something that cold oil (ie 85F) is going to hurt an engine. I'm not saying that cold oil like 0F can't hurt the engine. I've had customers tell me this for years that say that an oil temp at 130F will hurt an engine and 180F is the minimum you should run in an engine. Any truth to this?
I've yet to find any data to back this up though. The only specs I've found said that if temps were below 20F then warm the engine and oil up. With todays multiweight oils, I just can't think of something that cold oil (ie 85F) is going to hurt an engine. I'm not saying that cold oil like 0F can't hurt the engine. I've had customers tell me this for years that say that an oil temp at 130F will hurt an engine and 180F is the minimum you should run in an engine. Any truth to this?





RE: Too Cold Oil Temperature??
The oil being at to high a viscosity can cause engine damage by the pressure going to high or the flow being to restricted.
The pressure to high causes broken oil pump drives and blown oil filter canisters. This then causes a total loss of oil supply to the engine. I have seen this happen. The engine in question was driven quite a few miles after the canister burst. It was driven to a stall at WOT in low gear on a flat road. The result was not pretty. We recovered the cam, inlet manifold, exhaust, ignition system and the heads after a lot of repairs on the heads.
The restriction causes the oil to be lost out the pressure relief valve instead of circulating to all required areas. Damage results from oil starvation even though the gauge shows very high pressure.
A co-incidental cause is that if the oil is real cold, the engine internals are also cold and clearances might be so far out from suitable running clearances that damage results, eg, piston to bore is to big and the pistons slap hard enough at WOT high rpm that they crack the skirt off behind the oil ring grove.
It is impossible to associate this with a specific temperature as it depends on engine internal clearances, grade of oil, size of oil pump, strength of oil pump drive system. oil gallery layout, rate of warm up and temperature profile across engine components, strength of oil filter canister etc etc.
Regards
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RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
You just asked a completely different question.
If the normal operating temperature is to low, water builds up in the crankcase or sump and contaminates the oil. If the normal operating temperature is close to water boiling point, the water will be flashed off, thus cleaning the oil of the water contamination.
Use of the site google feature would have shown you that this has been already discussed in detail in previous threads.
Regards
eng-tips, by professional engineers for professional engineers
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??
RE: Too Cold Oil Temperature??