Been snowed in a bit lately and have spent more time (than usual) trying to understand oil capacity and demand. Have a few basic questions:
1. When does an engine demand the most oil? I've always assumed it was at high RPMs.
1a. In a typical engine, does a pump send out more oil at, say, 5000 RPM than 4000 or is there a max output that is reached sooner?
2. In a typical engine/pan, what is the greatest percentage of capacity that is ever in use at once? For instance, in a 6 qt. system, how many of those 6 qts. are out "working" and how many are waiting in the pan to be pumped up into action? ( The origin of this question is my friend's Jeep, after his wife ran it for an extended period with only around 3 qts. in the 5.75 qt. system.)
3. Do some engine designs just require more oil to properly lubricate while in operation? I have owned the Jeep 4.0s that have 6 qt. systems, and now a 5.3 GM that also takes 6. The GM engine is about 25 percent bigger yet their manufacturers required the same amount of oil.
Thanks for enlightening me.
1. When does an engine demand the most oil? I've always assumed it was at high RPMs.
1a. In a typical engine, does a pump send out more oil at, say, 5000 RPM than 4000 or is there a max output that is reached sooner?
2. In a typical engine/pan, what is the greatest percentage of capacity that is ever in use at once? For instance, in a 6 qt. system, how many of those 6 qts. are out "working" and how many are waiting in the pan to be pumped up into action? ( The origin of this question is my friend's Jeep, after his wife ran it for an extended period with only around 3 qts. in the 5.75 qt. system.)
3. Do some engine designs just require more oil to properly lubricate while in operation? I have owned the Jeep 4.0s that have 6 qt. systems, and now a 5.3 GM that also takes 6. The GM engine is about 25 percent bigger yet their manufacturers required the same amount of oil.
Thanks for enlightening me.
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