Oil overfill- H6- how much before a problem?

[CNY_Dave]

Changed the oil in my '03 H6- ended up a little over 'full' on the dipstick (although it was a change with filter, and I did not put in more than 6qts).

 

How much above 'full' can you gert away with- 1/4 qt? 1/2 qt? 1qt?

 

I know the answer is pretty much 'as long as its not getting thrashed areound by the crank', but how high is that, I wonder?

 

Dave

[OB99W]

[...]How much above 'full' can you gert away with- 1/4 qt? 1/2 qt? 1qt?

 

I know the answer is pretty much 'as long as its not getting thrashed areound by the crank', but how high is that, I wonder?

I don't know for sure, but I can't imagine 1/4 qt or a bit more being any sort of problem. If any crankcase (H6 or whatever) is overfilled by closer to a full quart, I'd remove the excess rather than chance aeration.

[Durania]

How about draining the oil down into the nominal level on the dipstick and give yourself peace of mind?

[Manarius]

1/4-1/2qt probably won't be too bad. It'll leak or burn out soon enough.

[aircraft engineer]

Well... if you wanted just a 1/2 qt drain and were willing to pull off the oil filter, dump it out and put it back - that would work. Those face sealing rings are "tough" - at least tough enuf to take off/on one time. Just check for "nicks" and don't damage it when removing and it will be OK to re-use That's the best part about the grit end Frams - easy OFF easy ON

[1075]

Well... if you wanted just a 1/2 qt drain and were willing to pull off the oil filter, dump it out and put it back - that would work. Those face sealing rings are "tough" - at least tough enuf to take off/on one time. Just check for "nicks" and don't damage it when removing and it will be OK to re-use That's the best part about the grit end Frams - easy OFF easy ON

 

Personally, I would avoid Fram filters with the exception of the gray ones. Fram got low ratings in Consumer Reports awhile back and check out the bottom of this page;

 

http://people.msoe.edu/~yoderw/oilfilterstudy/oilfilters.html

[aircraft engineer]

I'd use some other filter if they had the grit end. It's about the only thing I like about them (yeah, I've looked at the cut-ups) - but for 3000 miles and regular changes, they seem to be ok.

 

Since the worst part is when the engine starts and the cold UNFILTERED oil goes into bypass, it's kind of a moot point anyway.

[CNY_Dave]

I'd use some other filter if they had the grit end. It's about the only thing I like about them (yeah, I've looked at the cut-ups) - but for 3000 miles and regular changes, they seem to be ok.

 

Since the worst part is when the engine starts and the cold UNFILTERED oil goes into bypass, it's kind of a moot point anyway.

 

How bad it is depends on how contaminated 'unfiltered' oil is compared to the filtered oil.

 

That 'unfiltered' oil has of course been filtered before its 'last pass' through the engine, so the only crud in it should be whatever the engine produced in a few-seconds worth of running.

 

So how much crud does that actually amount to?

 

 

Dave

[aircraft engineer]

not a whole lot. That pass thru the filter might have been the last before shutting down, but the first pass thru the filter depends on how fast the oil gets up to temp (thins out) so it is likely more than "one pass" thru the engine

 

BTW - One of the reasons I tend to not worry too much about filter brand is that IF they are changed eveny 4000 or so, they don't matter all that much. Years ago when engines were "open" the crud that came in thru the breather plus the breakdown of the fuel was what made oil "dirty" - remember that oil never wears out - it just gets dirty and the abrasive content in that dirt is what causes engine wear. Change oil more often and wear goes down.

 

The SAE filter test sets "minimums" for sure, but the intent isn't to run the filter to a "loaded" condition and determine "max operating life" anyway. The filter just picks up the macro chunks anyway - down to 20 microns

[OB99W]

[...]Since the worst part is when the engine starts and the cold UNFILTERED oil goes into bypass, it's kind of a moot point anyway.

Engine wear on cold start with most piston engines doesn't have a lot to do with abrasive particles that are suspended in the oil (and the particles big enough to settle out obviously aren't an issue). It tends not to be a "bottom end" problem, but a "top end" one -- there are high-pressure points in the valve train (in particular, lifter/cam interface) that have little lubrication initially, and there can be actual metal-to-metal contact at first.

 

 

[...]- remember that oil never wears out - it just gets dirty and the abrasive content in that dirt is what causes engine wear.

The base stock doesn't "wear out", but there are several other factors beyond "abrasive content" that contribute to wear -- additives are depleted, oxidation occurs (typically more so with "dino" oil than synthetics), combustion byproducts other than abrasive ones contaminate, fuel dilution happens, etc.

 

 

Change oil more often and wear goes down. [...]

Agreed, for several reasons, but don't overdo it.

[stevetone]

...remember that oil never wears out - it just gets dirty and the abrasive content in that dirt is what causes engine wear...

+1 on the additives wearing out.

 

It's the viscosity additives that wear out, according to the excellent articles at Motor Oil by AE Haas:

 

"The downside of a mineral based multigrade oil is that this VI additive wears out over time and you end up with the original straight 10 weight oil. It will go back to being too thin when hot."

 

There's a lot of good info there. It's quite a schooling on oil...

 

Steve