oil foaming in sight glass

Anyone have this problem. Warmed the engine up and drained oil. It came out all frothy. Put the new oil in started it up and watched it whip up in the sight window.

R1150GSA 2004

The foaming is likely due to water moisture in the oil. Prior to dumping the oil it needs to warm up from a ride not just a rev up in the driveway. Others may disagree.

I drain engine oil cold. No chance of fresh condensation and all the junk is sitting in the sump with the help of gravity. Even after a ten minute ride, there is a greater volume of oil dispersed throughout the engine than if you just drop the drain plug on the cold engine.

Also, a cold engine is a pleasure to work on as opposed to a hot one.

If your engine oil is entraining air, you may have a leak on the suction side of one of the oil pumps requiring engine teardown.

Or, you may be overfilling and whipping air into the oil.

Or, you may have a crankcase ventilation issue.

But, air in oil is not good because the film strength is severely compromised by the air (air is a lousy lubricant).

How much oil are you putting into the engine during the oil change?

I agree!

Jim

Then the question is, where is all that water coming from?

I fill it to the 3/4 up the sight glass. Checked it tonight and the bubbles are gone. I will fire it up and see what happends.

How common is it to have oil pump issues?

Generally multiple short trips where condensation doesn't have a chance to burn off. This is why you should do one trip a week of at least half an hour.

Jim

Virtually never!

Jim

I thought this was true too. You ride the bike hard and park it all the gunk and hot oil should be at the bottom ready to drain out. Just won't come out as quickly when cold but heavy gunk should be the first thing out.

Water in the oil can be caused by a cracked engine and coolant getting into the oil.

You should drain the coolant and check for oil.

What coolant...?

eggzactly!

But, not to start a "oil" thread - but, a warm engine is a warm engine. I do not believe that the motor knows the difference in temps between when its hot from riding, and hot from idling.

I do believe the key is to get the motor hot - period. If its idling, then it needs to idle until the temp gauge reaches normal operating temperature. Otherwise, you will not bake/cause evaporation of the condensation out of the oil and the muffler/exhaust...

Never mind the foam, what colour was the oil when it settled? If the oil is contaminated with water it will ALWAYS be a milky shade. If it aint off white, start looking for air entry in the pump .

Very rare...so, don't listen to this old f _ _ t. Also, the OP is filling his engine with the correct amount of oil so, whipping the oil is not the issue.

But, excessive water in engine oil from condensation is a concern. If condensation is the source (and it appears that it is) further investigation is needed or, a change in riding habits.

Now, I'll just go to the garage and repair my 20 year old Maytag Neptune washing machine.

The wet oil needs to exceed 212 F. in order to boil off the condensation. This means a ride of adequate length and the engine oil at 212 F. + for an extended period.

You'll likely get comments regarding idling the engine to operating temperature rather than riding the engine to operating temperature.

Also, I believe the crankcase vent will expel the crankcase gasses and condensation. So, check your crankcase vent for moisture (JVB, I believe the vent terminates in the air box?).

You should rethink that.

Heat in these motors is directly proportional to fuel burned, and a lot more heat is generated by high rpms than by idling. Especially when the high rpms are associated with trying to drag the bike though the air at high speeds. A period of idling after a high-speed run is likely to cool your motor down.

Definately start with color. If it looks like coffee with creamer or lighter it is likely water.

Where do you live? What is the weather like lately? Stored indoors or outside? Been riding in rain? Offroad with stream crossings, even if shallow?

I am with JVB that it is likely not a serious engine problem like a cracked block or bad oil pump unless there has been some sort of trauma to the bike like a crash or some crazy over heating issue.

Condensation happen when temperatures change, think of a glass of ice water with sweat on the outside. The cold glass from the cold drink inside pulls water from the warmer air around the glass and it condenses on the glass. The crankcase in vented so there is air in the crankcase. Get the outside air cool enough and shut off a warm engine and it could pull moisture out of the air in the crankcase and condense it inside the cases. Start the bike and the running motor collects that oil and whips it into the oil, frothing it up like whipping cream.

Just a side note. One of the reasons we don't use auto oil in small airplanes and stick to aviation oils is because of the foam inhibitors used in aviation oil. altitude affects foaming. chip