oil level rises overnight?

[Teutonics]

Okay, I hate to ask this question because it is probably stupid, but I searched the archives and couldn't find any similar information.

My issue is that when I run the bike and get the oil warm and shut down the bike, the level is in the middle of the sight window...stays that way for at least an hour or more.  Great.  However, the next morning after the bike has sat and cooled, the oil level is well above the sight window.  WTF?  Is this indicative of a problem?  Is there some sort of check valve for the oil cooler that is failing?  Or do I have a blockage somewhere that isn't allowing the oil to drain back down?

[ducpainter]

You haven't said what bike, but I'd guess your vacuum petcock is filling the cases with gas.

If you have a bike w/ carbs...Don't run it until you get it fixed. The diluted oil won't protect your engine.

[Slide Panda]

His sig line says a 02 900, so injected.

[ducpainter]

His sig line says a 02 900, so injected.

I should look a little closer next time...

To the OP

Does the oil in the engine smell like gas at all?

[Teutonics]

Does the oil in the engine smell like gas at all?

No, no gas.  If I start and run the bike and warm it up, then shut down the oil level is fine again... until the next day.

[ducpainter]

The oil in the engine should drain back in less than an hour.

Most Monster coolers have the fittings on top so I wouldn't think it's the cooler draining although I guess as things cool some sort of siphon could occur. There is a check valve in the pump. Does your oil light go out immediately when you start?

You are checking the level with the bike level and upright...correct?

[Teutonics]

The oil in the engine should drain back in less than an hour.

I haven't watched it closely to see how long it takes, but this statement makes me hope makes it sound like it could be normal.  When cold the level should/could be above the marks and/or window?  I'll try warming it up tonight and check every 5-10 minutes thereafter.

Most Monster coolers have the fittings on top so I wouldn't think it's the cooler draining although I guess as things cool some sort of siphon could occur. There is a check valve in the pump. Does your oil light go out immediately when you start?

Yes, no problems with the oil light staying on.

You are checking the level with the bike level and upright...correct?

Yes, the bike is parked on a center stand in my garage.

Thanks for the help so far!

[ducpainter]

I haven't watched it closely to see how long it takes, but this statement makes me hope makes it sound like it could be normal.  When cold the level should/could be above the marks and/or window?  I'll try warming it up tonight and check every 5-10 minutes thereafter.
Yes, no problems with the oil light staying on.
Yes, the bike is parked on a center stand in my garage.

Thanks for the help so far!

Normally the cold level will be slightly lower.

How much oil do you put in the bike when you change it?

[Teutonics]

How much oil do you put in the bike when you change it?

3.5ish quarts/liters.  Not sure on the exact amount because I use the Rotella T6 synthetic in the gallon jug, and have some left in the bottle. 

Oil change consists of warm the engine to get the oil hot, drain oil, and refill to below the low-level mark to account for expansion.  Warm up engine and fill to recommended level.  Everything is fine until the next day when it is over-full again.  Start it up, warm it up, shut it down, and oil level is fine... until the next day.

My guess is siphon from the oil cooler, but is that normal?  Is there a diagram of oil flow that I could reference to see where the check valve is in relation to the oil pump and oil cooler?

[Speeddog]

You're checking the oil level with the bike on it's wheels, right?

[ducpainter]

3.5ish quarts/liters.  Not sure on the exact amount because I use the Rotella T6 synthetic in the gallon jug, and have some left in the bottle. 

Oil change consists of warm the engine to get the oil hot, drain oil, and refill to below the low-level mark to account for expansion.  Warm up engine and fill to recommended level.  Everything is fine until the next day when it is over-full again.  Start it up, warm it up, shut it down, and oil level is fine... until the next day.

My guess is siphon from the oil cooler, but is that normal?  Is there a diagram of oil flow that I could reference to see where the check valve is in relation to the oil pump and oil cooler?

My bike doesn't do it...

and I haven't seen any others do it.

I wouldn't call it normal.

There is a diagram of the oil circuit posted somewhere here in tech.

[Howie]

Are you checking the level with the bike verticle, both wheels on the ground then looking at the level the next morning with the bike on the center stand?  The oil level will be slightly higher on the centerstand since the bike is no longer level.

[64duc]

3.5ish quarts/liters.  Not sure on the exact amount because I use the Rotella T6 synthetic in the gallon jug, and have some left in the bottle. 

Oil change consists of warm the engine to get the oil hot, drain oil, and refill to below the low-level mark to account for expansion.  Warm up engine and fill to recommended level.   Everything is fine until the next day when it is over-full again.  Start it up, warm it up, shut it down, and oil level is fine... until the next day.

My guess is siphon from the oil cooler, but is that normal?  Is there a diagram of oil flow that I could reference to see where the check valve is in relation to the oil pump and oil cooler?

If you are refiling to level without letting the oil drain after you warmup, that could be the cause. Fill to level cold, warmup, and then let sit for a few minutes and check level. All with the bike on the centerstand.

[Teutonics]

You're checking the oil level with the bike on it's wheels, right?

Not exactly, I have a center stand (not kickstand) on my bike. 

Are you checking the level with the bike verticle, both wheels on the ground then looking at the level the next morning with the bike on the center stand?  The oil level will be slightly higher on the centerstand since the bike is no longer level.

All checks are done on the center stand (not kickstand).  The variance would be front to rear instead of side to side (very small, my back tire rubs the ground when on the CS), however the variable front/rear is constant so is not the cause of the change in level.

If you are refiling to level without letting the oil drain after you warmup, that could be the cause. Fill to level cold, warmup, and then let sit for a few minutes and check level. All with the bike on the centerstand.

Yes, this is what I do, although how long to let it sit is the question.  I usually wait 10-15 minutes to refill, but wondering if I should be waiting overnight to refill to the proper level?  I don't think so, because then the bike is cold.

It figures I would be the only one with this issue.  My gut feeling is that it is the check valve letting the oil drain back from the cooler over an extended period of time.

[ducpainter]

The oil level will change with a variance in level front to rear.