Extra oil in crankcase - Not a good thing?

[Seth]

Did my oil change yesterday. Poured 5 litres in my mitsu outlander even though it is spec'd for 4.4 ltrs (including filter).

I know you are supposed to put the right amount and later add more as and when required.. But, I always pour in 5 quarts (4.75 ltrs) and usually get about 4 quarts (3.8l) back after my long ocis (8k miles). So, I figured putting some extra would do no harm.

But today I was told by dealer mechanic (I was on the phone for something else and wound up having a chat) that excess oil causes aeration which could damage engine. Also, it supposedly puts extra load on engine somehow.. Anything to worry about?

 

[Quest]

yes, it is indeed not a good thing to severely overfill your crankcase and the mech is indeed correct that excessively filled crankcase will lead to oil aeration, which may lead to partial engine failure due to air bubbles in oil bearings.

 

[nicholas]

.6 litres is not really over filling - I always over fill .4 to .5 quarts in all my engines------- no problems over the last 12+ years of car ownership.

1+ extra quart is getting a little high

im sure others will chime in

 

[Bryanccfshr]

I always round up by the half quart. My Tacoma takes specs 5.5 qts and I use 6. The jeep takes 6. Nice round number 6.

 

[IndyIan]

I know some guys slightly overfill for track days, so they don't get oil starvation on long corners. Half quart should be fine, but if your worried, drain some, or don't rev it very high.

I do have some experience with aeration though, I overfilled maybe 1.25 litres in my neon, kind of on purpose as it used to leak oil from the headgasket, but normally I didn't overfill that much. A week later I was fooling around with my new scangauge(displays rpm among other things) seeing what the tranny actaully shifts at since the car doesn't have a tach. So I've got it matted and I'm watching the rpm rise on the scangauge and at 6400 rpm the oil light pops on!

I let off right away and put it into N and then shut off the engine and stopped on the shoulder cursing at myself... After a quick inspection under the hood and seeing no oil trail of death, I crossed my fingers and started it up. Oil light went off right away like normal and gingerly drove home. I did a quick search online for what actually happened and found out it was aeration... Nothing seems to have changed although I'm sure a bearing or two has had their life shortened. I am just glad I caught it right away.
Ian

 

[demarpaint]

I've always rounded up anything that ended with 1/2 qt, and never had a problem. I wouldn't want to go much over that though.

Frank D

 

[02zx9r]

over filling by a half quart to 1 quart will not cause issues.

10 quarts over is a problem

 

[c3po]

I would think that this would only be an issue if you were constantly at 5000 rpms. The faster the engine rpms, then that's when more oil is whipped around by the crankshaft.

This may be a question for Gary Allan.

 

[TallPaul]

Originally Posted By: IndyIan
... So I've got it matted and I'm watching the rpm rise on the scangauge and at 6400 rpm the oil light pops on!

I let off right away and put it into N and then shut off the engine and stopped on the shoulder cursing at myself...
You need to drain some off to a normal level and go back out and repeat everything. If the oil light still comes on then it is not the overfill, but maybe an oil starvation issue at that high rpm for whatever reason. Not likely but worth a check.

 

[TallPaul]

Originally Posted By: Seth
Did my oil change yesterday. Poured 5 litres in my mitsu outlander even though it is spec'd for 4.4 ltrs (including filter).
Look at your owner;'s manual and see if it allows for overfill. My Ford manuals usually show that the oil can be as much as about half inch above the full mark. They usually state it by a diagram showing a range from the full level to the "F" in the word full, which is above the full level area on the stick. Then it states it may be in this range after an oil change, but not to add oil into that area. Finally it states if the oil is beyond the F, engine damage may occur.

 

[oldmaninsc]

Originally Posted By: demarpaint
I've always rounded up anything that ended with 1/2 qt, and never had a problem. I wouldn't want to go much over that though.

Frank D


I agree. Most of my vehicles are usually an 1/8" - 1/4" above the full line on the dipstick and I've never had a problem. But I would never go more than 1/2 quart over.

 

[Seth]

I hope that some extra oil is taken into consideration when they designed and tested these engines.. Too bad if they didnt. I wont be buying their product again. That being said, I dont plan on jacking it up and creeping under the car again.. especially just to remove extra 0.6 ltr. Bleh...

 

[ThirdeYe]

My mom's Malibu takes 4.5-4.6 quarts w/filter (depending on the source) but I always dump in 5 quarts and call it good and change it every 5k using Havoline Synthetic that I got on sale. Next time around though, I'm gonna try using the oversized PF52 oil filter (if it has clearance) and that way I won't have to worry about putting in 5 quarts, since the oil filter is pretty big compared to the PF47-size I usually use.

 

[ted s]

you worry too much

 

[IndyIan]

Originally Posted By: TallPaul
Originally Posted By: IndyIan
... So I've got it matted and I'm watching the rpm rise on the scangauge and at 6400 rpm the oil light pops on!

I let off right away and put it into N and then shut off the engine and stopped on the shoulder cursing at myself...
You need to drain some off to a normal level and go back out and repeat everything. If the oil light still comes on then it is not the overfill, but maybe an oil starvation issue at that high rpm for whatever reason. Not likely but worth a check.

It was 20,000km ago and I've done some high rpm driving since then and no oil light so I think it was the foaming. I also use better oil now, and at the right level since the headgasket was replaced. The engine is surprisingly quiet with no lifter ticks etc, so I think I'm good.
Ian

 

[JonnyHotcakes]

An engine should be able to tolerate a quart and a half to a quart with no issues.

I know I've done it doing oil changes on 4 bangers several times.

 

[Pablo]

Dealer mechanic knows something......but he should have quantitated his statement a bit. 1/2 quart over will not strain the engine or cause aeration (via crank contact). Think about 16 oz of oil....it's just not that much oil. Either spread over the surface of the oil pan, or through the whole oil system.

 

[mechtech2]

Your biggest problem is that you used a 1/2 qt that you should have saved for the next oil change!

Spread out 1/2 qt over the area of an oil pan, and it would be a very minor change in height/depth.