How long does oil protect surfaces on startup?

Joined
Jun 30, 2022
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How long does the residual oil in the engine protect the internal surfaces and bearings on startup? I ask because I was cleaning my car out and when I installed the floor mats I must have gotten them wedged between the brake and gas pedal. When I pressed the brake to start the truck it must have pushed down the gas pedal because as soon as the car started it went straight to redline which is about 6000 rpm on my Tacoma. I had driven the truck about 2 miles to the car wash and it was turned off for about 20 minutes. I’m a little worried that I may have damaged something since I doubt oil pressure would have built up prior to it hitting redline. It’s not knocking and I don’t see any smoke but I’m worried that I may have compromised the bearings and will end up with issues down the road.

One thought I had is that since the oil pump works off the crank, it shouldn’t really matter if the truck idled at 800 rpm for 7 seconds or if it rev’d up to 6000 rpm over the course of a second. The amount of rotations the pump would have made would have been the same so about the same amount of oil should have flowed through the engine. I’m not sure if this logic is true, I’m just trying to rationalize whether or not I could have done any damage to the engine.

What do you all think?
 
Joined
May 17, 2009
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If its running good you are good. Don't you have a rev limiter?

The worse that could happen is you knocked some carbon off the piston top an sometimes this migrated to a spark plug fouling it. But - if it runs good and get same or spec fuel mileage you are fine.

No use doing some anguish-inducing mental exercise. Bearing are running on a polished journal and the cohesive forces and capillary forces hold the oil in there. Any engine I have taken apart has had oil wetted bearings.

You got oil going in there before the revs raised.
 
Joined
Mar 2, 2004
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3,504
Location
Kentucky
I did a lot of unscientific tests doing stupid things to vehicles in my younger years.

One of those "tests" was redlining the engine for sustained periods (20 seconds or more) immediately after startup, I thought it was fun to try it when the weather was especially cold. These were on Ford 5.4/6.8L V8/V10 engines and they drove fine for years with no ill effects.

I don't think you have anything to worry about!
 

Yota94

Thread starter
Joined
Jun 30, 2022
Messages
2
If its running good you are good. Don't you have a rev limiter?

The worse that could happen is you knocked some carbon off the piston top an sometimes this migrated to a spark plug fouling it. But - if it runs good and get same or spec fuel mileage you are fine.

No use doing some anguish-inducing mental exercise. Bearing are running on a polished journal and the cohesive forces and capillary forces hold the oil in there. Any engine I have taken apart has had oil wetted bearings.

You got oil going in there before the revs raised.
Thanks for the sanity check! I do have a rev limiter but it happened so quick I didn’t register if it was hitting the limiter or not. I’m sure that would have prevented any damage from being over revved but my main concern was the bearings not getting enough oil during high rpm’s.
 
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