Revving the Engine at Start Up
Stellar HDF Member
Joined: Jan 2007
Posts: 2,627
Likes: 1,348
From:
It's certainly not good for the engine.
Much of an engine's wear comes from cold start-up - those first few seconds (or minutes) where lubrication is not optimal ... in some cases, for a short bit, not lubricating!
I expensive commercial applications there are pre and post lubers where oil (often pre-warmed) is pumped through the engine before start-up; post lubing is generally for providing oil tot he turbocharger(s) after shutdown because they continue to spin at high RPM and benefit from post shut down lubrication.
I said all of that to say this: the more strain or duty cycle (revs) you put on am engine int he first moments after cold start-up, the worse it is for that engine.
Much of an engine's wear comes from cold start-up - those first few seconds (or minutes) where lubrication is not optimal ... in some cases, for a short bit, not lubricating!
I expensive commercial applications there are pre and post lubers where oil (often pre-warmed) is pumped through the engine before start-up; post lubing is generally for providing oil tot he turbocharger(s) after shutdown because they continue to spin at high RPM and benefit from post shut down lubrication.
I said all of that to say this: the more strain or duty cycle (revs) you put on am engine int he first moments after cold start-up, the worse it is for that engine.
Stellar HDF Member
Joined: Jan 2007
Posts: 2,627
Likes: 1,348
From:
This video, particularly at 3:09 where neither rocker arm is getting much (if any) oil even though the oil is 175F degrees! The S&S rep even states (at about 3:10) that the illustration shows why you should not rev your engine right after start-up.
As an unrelated aside, I believe that the video "demonstration" is skewed because a harley's oil system pumps oil tot he rear cylinder first. I wonder how the "demonstration" would have gone had they installed the S&S tappets int he front cylinder and the Chevy tappets in the rear ???
Either way, the video clearly demonstrated why you should not rev your engine right after start-up ... even with hot oil!
As an unrelated aside, I believe that the video "demonstration" is skewed because a harley's oil system pumps oil tot he rear cylinder first. I wonder how the "demonstration" would have gone had they installed the S&S tappets int he front cylinder and the Chevy tappets in the rear ???
Either way, the video clearly demonstrated why you should not rev your engine right after start-up ... even with hot oil!
Seasoned HDF Member
Joined: Nov 2009
Posts: 15,705
Likes: 22,718
From: Farmington ,MS
Please explain the difference between an engine and a motor...
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Joe Kucinski
Seasoned HDF Member
Joined: Aug 2014
Posts: 35,239
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From: 40.2444° N, 75.6419° W
Harley-Davidson, converting gasoline to noise for 115 years.......
A motor uses electric, an engine is a modified "air pump" that uses fuel for combustion.
A motor uses electric, an engine is a modified "air pump" that uses fuel for combustion.
Last edited by Super Glidester; Sep 7, 2018 at 08:48 AM.