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Milky in oil fill tube but oil is clear.

B

bczoom

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OK guys, what's this one.

I have a small 5hp engine sitting on a generator.

When you pull the dipstick, it's milky in the fill tube but the oil itself is clean/clear. It is air cooled so there's no water.

Is it condensation or maybe some gas getting past the rings or something?

Ideas?

BTW, we've been changing the oil every 2 days but it still comes back.
 
How long's your genny running at a time? It would seem that the weather is too warm to have a condensation problem. If this were happening in mid-winter, I could see it. When you pull the stick, does the oil smell "gassy"? (no smart remarks, guys! :hammer:)

I'm assuming it's an air cooled engine.
 
Trakternut said:
(no smart remarks, guys! :hammer:)

I'm assuming it's an air cooled engine.
Click to expand...

OK, if you insist, but Zoomy said it was air cooled. :poke:


BC, I'd go with both yours and T-nuts diagnoses. Gotta be gas or condensate or rain water that got in the oil.

Did you smell your dipstick. :hide:
 
How long it been sitting without running. I'm betting condensation if it's been sitting up!
 
Running continuous? Splash lubrication? Might be foaming the oil to the point that part of it separates and is left in the tube. Wild guess there though.
 
bczoom said:
OK guys, what's this one.

I have a small 5hp engine sitting on a generator.

When you pull the dipstick, it's milky in the fill tube but the oil itself is clean/clear. It is air cooled so there's no water.

Is it condensation or maybe some gas getting past the rings or something?

Ideas?

BTW, we've been changing the oil every 2 days but it still comes back.
Click to expand...

Well if it is an air cooled engine, there is no way to control the engine's heat as in a water jacket cooled engine with a thermostat.

The air is keeping the engine from getting up to a "normal" temp like it would with the hot water and the dipstick tube is running even cooler, so it is causing the condensation on the inside of the tube. When you change the oil, it shouldn't be anything but a normal looking black oil that is getting changed.

The the water inside the dipstick tube is nothing to worry about and is even more normal if you are in a high humidity area, the milky look is where the oil mixed with the water vapor.... :thumb:

Er, you might check the Muffler Bearing though, it could be losing some backpressure...:poke:
 
I checked the muffler bearing as that was my first thought as well. It was fine.

When I first got the generator out, it had been sitting for awhile (like through the winter). We checked the oil, which looked fine, ran it for a day which is when we saw the white "stuff". Changed the oil and cleaned the tube. On this first oil change, the oil was pretty thin and although I have a terrible sense of smell, it did seem like there was some gas and the viscosity was thin.

We changed it again 2 days later. Oil viscosity was good. No indication of gas but the white stuff returned. Changed again 2 days later, same thing.

Temps have been in the 70's during the day, 40's - 50's at night (with a lot of dew).

I'll go with everything is normal/OK but still change the oil every 2 days which is 20 or so hours of run time.
 
bczoom said:
I checked the muffler bearing as that was my first thought as well. It was fine.

When I first got the generator out, it had been sitting for awhile (like through the winter). We checked the oil, which looked fine, ran it for a day which is when we saw the white "stuff". Changed the oil and cleaned the tube. On this first oil change, the oil was pretty thin and although I have a terrible sense of smell, it did seem like there was some gas and the viscosity was thin.

We changed it again 2 days later. Oil viscosity was good. No indication of gas but the white stuff returned. Changed again 2 days later, same thing.

Temps have been in the 70's during the day, 40's - 50's at night (with a lot of dew).

I'll go with everything is normal/OK but still change the oil every 2 days which is 20 or so hours of run time.
Click to expand...


You should be good to go, you could wrap the tube with insulation if you wanted and that would stop the condensation, but I wouldn't lose any sleep over it. Just a paper towel with foil around that would do.
 
Ohio's right. After I realized that the genny had sat for all winter, and since oil floats on top of water, instead of the other way around, I'm betting condensate. It'll take many oil changes to get rid of that water. Just keep on doin' what you're doing and, in a few more oil changes, you'll probably notice less and less of that milky stuff.
Sure glad we got that figured out, them muffler bearings are ex-pen-siiive!!!!
Don't ask how I know.
 
Well if you had water in the oil sitting in the bottom, the oil would have been milky all the way though the oil not just in the dipstick tube, once it got heated up that would evaportated out after the first hour or two of running...

If your engine doesnt' get hot because your load is light, it will keep a slight milky look off and on by the dipstick tube, it is the coolest thing on the engine from the inside. It isn't something to worry about if it is only on the dipstick tube. The coolest thing the moisture can stick to will be where the sludge will form. Basically, if you had water in the oil, it will be whipped into the oil within a few min's of startup and then will evaporate as it heats up.

Same thing kills peoples cars when they only drive a few min's, shut it down, then drive a few min's back and shut it down.... You can look at the oil and see that it was not gotten hot for nomal operation to burn the moisture (Sludge) out of it.

You would have gotten all the normal contaminates out after the first oil change after 20 hours of running. Changing now is just good maintance practices.
 
Hey, Foggy! Good thoughts. I guess I'm thinking along the same lines as you are, that the engine isn't pulling really hard for an extended period of time to evaporate the moisture out. That's why I'm thinking he's seeing it collecting on the tube because it's cooler there than in the crankcase. We're in the same church, just different pews! :tongue:
 
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