Revving and Priming

[camrydriver111]

When doing oil changes I've seen both technicians and DIYers alike rev the engine right after starting it after an oil change. I assume this is to circulate the oil throughout the engine faster. If you do that aren't you revving an engine with low oil pressure? My natural inclination tells me you shouldn't force it and only rev it once the low oil pressure light goes off. Is it better to idle the engine or to rev it right after changing the oil?

Which brings me to the subject of priming. Is it beneficial to prime oil filters or is it just OCD? Does priming really affect oil pressure on start-up or provide any benefits?

 

[JC1]

Originally Posted By: camrydriver111
When doing oil changes I've seen both technicians and DIYers alike rev the engine right after starting it after an oil change.


I wonder if they also do that to see if there are leaks?

I don't rev it up when I do my oil change. After the filter is tightened and drain valve on the fumoto are closed. I fill it up with oil. Then I look underneath to make sure there are no leaks on the garage floor.

After I start it up and look to see that the oil light goes off, i look back underneath the engine to make sure it's still not leaking.

Regards, JC.

 

[Brybo86]

I definitely wouldn't rev the engine with the oil pressure light still on

Priming the oil filter makes me feel good...

The oil light goes off a fraction of a second sooner.

I don't think priming vs not priming would significantly cause any change in the life of the engine.

An engine will go 300k with regular oil changes without having filter primed.

 

[abycat]

When I worked at my friends mr lube we would start the engine and make sure the light went out then held the rpm around 2000 to check for leaks since the oil pressure is fairly high at that engine speed. One tech under and one looking from the top. Then we would double check all the plugs and the filter. I don't Rev my own but I let them idle and check for drips and oil leaking.

 

[sicko]

My oil filter sits perfectly vertical, so I always pre-fill the filter since it's so easy to do. I don't know if it's as result of pre-filling the filter or not, but I've only had my engine oil light come on once, and that was just a single flicker and then it immediately went out. How long does the low oil pressure light stay on for everyone else?

My general process goes something like:

- Change the oil and filter, then check for leaks.
- Start the engine, then check for leaks.
- Drive around the block (0.5-1 miles), then come back and check for leaks.
- Rev the engine a bit, then check for leaks.

Assuming no leaks were ever seen, clean up the driveway and consider it a job well done.

 

[gregk24]

Priming the oil filter will help get the oil pressure up faster, but enough to make any difference? Who knows. Revving right after an oil change is a BAD idea. Just start it and let it idle on its own for a while. I usually let it idle for 1 minute after start up and use that time to check for leaks etc. Then back off ramps and consider it a job well done.

 

[Quest]

for properly carb'ed or EFI engines (warmed up), I never revv the engine 1st thing after oil change. I just crank until it catches, and let it idle until oil pressure builds up (which turns off the oil light on dash).

Q.

 

[Kuato]

Start. Idle. Check for leaks. No need to rev.

 

[michaelluscher]

Originally Posted By: Kuato
Start. Idle. Check for leaks. No need to rev.

Simple.

 

[riggaz]

No one should be revving any engine with the low oil pressure light on

Like starting a modern fuel injected car with your foot on the throttle to "get it going", It's just habitual stupidity

If you have a vertical facing oil filter then it certainly does not harm to fill them first but most oil filters are either element/housing types or spin on horizontal types that have shown no issues so far with regards to self priming.

 

[chrisri]

Revving an engine just after oil change is very stupid thing to do. Priming filter is OCD IMO. If you are really worried about this (you shouldn't be) , just pull ECU fuse and crank the pressure without actually staring the car.

 

[gregk24]

Originally Posted By: chrisri
Revving an engine just after oil change is very stupid thing to do. Priming filter is OCD IMO. If you are really worried about this (you shouldn't be) , just pull ECU fuse and crank the pressure without actually staring the car.

Or you could just fill the filter, easier.

 

[SteveSRT8]

Originally Posted By: chrisri
Revving an engine just after oil change is very stupid thing to do. Priming filter is OCD IMO. If you are really worried about this (you shouldn't be) , just pull ECU fuse and crank the pressure without actually staring the car.


This may be far worse than just starting it up for many engines!