Hubster, under which condition, cold or hot do you have the highest oil level reading on the dripstick?

Couple things are going on, oil is heating up and expanding and also aerating which adds volume, level goes up.

Butt sum oil is retained in the upper cylinder oil galleries etc after engine shutdown, so that would tend to lower the oil level depending on how long you waited to check it. No?

So is it higher cold or hot?

Hub it reads higher hot than when cold, quite a bit actually...

Interesting. I guess I can't say I've really ever did a before and after. Although I'm sure in many cases, the same vehicle has been checked when hot and when cold and I don't recall there seeming to be a significant difference, although again I can't say I would've checked even the same day.

I suppose that seems plausible. Although I wouldn't think it should be a lot, like a quart higher. I guess if I had to think, maybe a 10th of a quart? Not really sure what a 1/10th of a quart is on the sight glass, maybe 1/16", which would definitely be noticeable.

I'm suppose oil probably expands when it is hot. And engine internals also expand. And to think something like the engine block would only enlarge, no, I'd think it would expand from the middle of the casting and be slightly larger externally but equally smaller internally.

So is it higher cold or hot?

My deal is not measuring the 3.?qts with new filter and pour it in. My way is to fill the filter with whatever I poured in before installing, start it see the oil light go off then stop it. Then note within seconds if the level is between the lines. I then add if it is lower at the bottom line. I top it off just at the bottom line.

Then in the morning I know all has dripped off from the splash lube, and the top end is dry. That's all she wrote as static drop goes. Now I top it off to the level in the morning.

Some owner's manual tell you before riding to check oil. This manual says to upright the bike (cold) and note level is between the lines. So cold is the check. Higher level hot? Who cares, it showed cold-correct at the upright.

You know my experience of one of my beater break-in bikes dropped the level under the window, way before the 3k oil change. I lost power and turned around one day. Went thru the drill of checking for brake drag, wheel bearing seize, chain links. All passed. Why I looked at the oil level and saw no oil, no oil light at the dash, could change the power with a lower volume.

So short of the raggedge of overfill that soaks the air box, high level more helps than hurts.

Signed,
ASS-factor factored in

__________
My bad... more clicking the right side, [current date/time] not the left side [subject page] to see what I missed.

:Edit:
Forgot to address the aeration. If we are saying bubbles hugging the window, this sounds like a failed pickup seal at the oil pump path. I think if we are talking about the pickup tube is cracked above the oil level. Get it?

This is typical with automatic car trans. Mechanic is too lazy to replace the seal that comes with the pump filter.

* Last updated by: Hub on 7/21/2023 @ 11:53 AM *

Hubster that's good information, what happened to the beater break-in bike that had the oil level below the window? Was it DOA? Lost power sounds pretty serious, lettuce bee thankful if it lived...