Proper Way to check engine oil level on Yanmar 2YM15

[facciatosta]

The tag on the dip stick reads check oil level 10 minutes after engine stop.
10 minutes or sometime 20 minutes later I pull out the dip stick and it's dry.
I put it back pull out again and oil is above the full level.

I have talked to the mechanic and he said I need to open filling plug, there are two of them. Same thing. Check oil level next morning and it is above the full level.
Engine does not burn oil and does not drip.

60 engine hours ago I changed the oil and fill it up per specification.
Oil level alarm does not go off when engine is running.

When do I see correct level when I pull dip stick first time or second time? Shall I add oil or remove the excess of it?

Thank you.

[pcmm]

The dipstick on my Yanmar is a very sung fit (It has a rubber stopper built into the dipstick) which while the engine is running and all the oil is circulating causes the bit of oil in the tube to get sucked out. checking the oil 10 minutes later allows all the oil to flow back to the pan.

When I check my oil I just pull the dipstick out by an inch (to break the seal) and leave it for a few minutes while I check the filters, belts and hoses, etc. I then come back to the dipstick and pull it out, do the wipe on a rag and then do the normal check. Solves the confusion of why there is no oil displaying. Learned that one the hard way when doing oil changes! over filled once and had to pump out some oil to get back down to the full mark.

[Rob_P]

Overfilling your crankcase with an extra quart of oil isn't horrible but it's not ideal either. It can lead to foaming the oil from the crankshaft beating it like whipping eggs, or blowing raw oil out the crankcase breather.

Drain that extra quart and do what PCMM says about "popping" the dipstick for a minute or so before checking. Always check twice.

The 10 minute wait time is to let the oil drain back down from the top of the engine into the oil pan before you check it. If you don't do that, you could end up with a low dipstick reading even though you have plenty of oil.

Best way to do it is first thing before starting the engine. Pop the dipstick, check the engine over for obvious signs of needed repairs, check the water level in the cooling system (if it's freshwater cooled) and for leaks, then push the dipstick back in before removing it to check the oil level. Twice.

[facciatosta]

Originally Posted by pcmm

The dipstick on my Yanmar is a very sung fit (It has a rubber stopper built into the dipstick) which while the engine is running and all the oil is circulating causes the bit of oil in the tube to get sucked out. checking the oil 10 minutes later allows all the oil to flow back to the pan.

When I check my oil I just pull the dipstick out by an inch (to break the seal) and leave it for a few minutes while I check the filters, belts and hoses, etc. I then come back to the dipstick and pull it out, do the wipe on a rag and then do the normal check. Solves the confusion of why there is no oil displaying. Learned that one the hard way when doing oil changes! over filled once and had to pump out some oil to get back down to the full mark.

Thank you, I'll do that. Dipstick on my engine fits snug too. I did notice there is small hole on the top of the tube, wonder if it suppose to eliminate the vacuum.

[facciatosta]

Originally Posted by Rob_P

Overfilling your crankcase with an extra quart of oil isn't horrible but it's not ideal either. It can lead to foaming the oil from the crankshaft beating it like whipping eggs, or blowing raw oil out the crankcase breather

In fact, I did the engine compartment surface was oily. We were on the anchor and I did not have the pump. So I got silicon tube that fits tight to the dipstck tube and sucked out some of oil.

[Compass790]

Wow to me it looks like you have the bare minimum in there.
From your photos the oil on your dipstick does not go all over it, thats just the stuff that you have got smeared on it pulling the dipstick up the tube when checking it.
You have to fill it up till the oil is completely covering the dipstick on both sides up until the top mark. It should look the same as the little section below yr bottom mark.

It may only be 500 ml but its important if you motorsail heeled.
Put say 250cc in & see what the dipstick looks like then.

[CassidyNZ]

The dipstick has to be in the oil to give a correct reading. While this may sound obvious here’s the thing: When I pull the dipstick, one side shows a level above the full mark, the other side shows a reading that is below the Low mark. Which is correct? Well, obviously the one that is below the Low mark. Because if the oil level is higher than that, there is no possible way the face of the dipstick can be dry.

The other side is picking up an erroneous reading from oil deposits left on the the dipstick tube which can show higher than reality. The lower reading on the other side of the blade cannot be erroneously low. It’s either in the oil or it’s not.

[facciatosta]

"Wow to me it looks like you have the bare minimum in there.
From your photos the oil on your dipstick does not go all over it, thats just the stuff that you have got smeared on it pulling the dipstick up the tube when checking it."

"The other side is picking up an erroneous reading from oil deposits left on the the dipstick tube which can show higher than reality."

Those were my initial thoughts. I panicked and overfilled engine with oil
No, it is not a smear. As previous commenters mentioned I checked not twice but many times.
Then engine had about 240 hours, does not produce visible smoke, does not leak the oil, It was filled per spec with 2 liters of oil. Where did oil go?
I lean heavily toward "the vacuum" theory. Especially because the pin hole on the top of the dipstick tube is definitely blocked by the the collar of the dipstick( design flaw or intentional?). I had to literally suck out some oil through the dipstick tube using the silicon tube and until I blocked that hole with my finger oil would come out.

[beirutsailor]

I ruined one Yanmar by overfilling. Every experienced mechanic I have asked since told me never to fill completely to the top level, and to check half an hour after engine stops for the day.

[Scubaseas]

Originally Posted by CassidyNZ

The dipstick has to be in the oil to give a correct reading. While this may sound obvious here’s the thing: When I pull the dipstick, one side shows a level above the full mark, the other side shows a reading that is below the Low mark. Which is correct? Well, obviously the one that is below the Low mark. Because if the oil level is higher than that, there is no possible way the face of the dipstick can be dry.

The other side is picking up an erroneous reading from oil deposits left on the the dipstick tube which can show higher than reality. The lower reading on the other side of the blade cannot be erroneously low. It’s either in the oil or it’s not.

This exactly.

Always take the lower of the two and repeat several times if in doubt. You may be picking up oil in the tube giving a false reading. Take the dip stick out and wait 5 to 10 minutes then check again if needed.

[CassidyNZ]

Originally Posted by facciatosta

Those were my initial thoughts. I panicked and overfilled engine with oil
No, it is not a smear. As previous commenters mentioned I checked not twice but many times.

Sorry to repeat but if the oil is higher than the dry part shown on one side of the dipstick blade, how is it possible that that part of the blade stayed dry? Yes, the high mark is definitely a smear. The oil level is what it is and a portion of the blade cannot possibly stay dry if it is immersed in oil.

And I agree with another post and will say that I never fill my sump to the top mark on the dipstick. I always aim to be between the two marks. Filling to the top mark will result in the oil being burnt off in a short space of running time.

[pcmm]

Originally Posted by CassidyNZ

Sorry to repeat but if the oil is higher than the dry part shown on one side of the dipstick blade, how is it possible that that part of the blade stayed dry? Yes, the high mark is definitely a smear. The oil level is what it is and a portion of the blade cannot possibly stay dry if it is immersed in oil.

And I agree with another post and will say that I never fill my sump to the top mark on the dipstick. I always aim to be between the two marks. Filling to the top mark will result in the oil being burnt off in a short space of running time.

Why would filling oil to the top mark result in oil burn off? The top mark is the result of putting in oil to the manufacturers specifications and is how ALL oil changes are done (automotive and marine). I can verify that what the OP is showing is normal with Yanmar. When I do my oil change and put in the specified quantity of oil the dipstick will look like the first picture until you “pop” the cap and give the oil a chance to level out in the dipstick tube. The “smear” is what ou see when you recheck the oil after a few minutes of letting the oil level up in the tube.

[CassidyNZ]

Originally Posted by pcmm

Why would filling oil to the top mark result in oil burn off? The top mark is the result of putting in oil to the manufacturers specifications and is how ALL oil changes are done (automotive and marine). I can verify that what the OP is showing is normal with Yanmar. When I do my oil change and put in the specified quantity of oil the dipstick will look like the first picture until you “pop” the cap and give the oil a chance to level out in the dipstick tube. The “smear” is what ou see when you recheck the oil after a few minutes of letting the oil level up in the tube.

We all have our opinions . . . . I know that when I fill my sump to the top mark the level drops fairly quickly to halfway down then slows right down in its journey to the bottom mark. So I don’t waste oil filling to the top mark. YMMV.

The “smear” after filling the sump is the oil that is left in the dipstick tube from the first time you pulled it out to check the level. The same smear occurs after a period of running because oil splashes into the tube while engine is running. The tube doesn’t reach far enough into the crankcase to be immersed in oil.

I stand by my statement that there is no possible way a part of the dipstick blade can stay dry if the oil level is higher than that point. C’mon, that’s not me being clever, it’s a simple fact.

[sierramerkur]

The number and variety of responces here are mind boggling. I had my oil changed once and someone broke my dip-stick. Another grease monkey pulled a dipstick off a parts motor and wanted to use it on my engine.

THIS IS HOW YOU KNOW WHERE THE OIL LEVEL IS SUPPOSED TO BE AND LEARN ABOUT YOUR ENGINE: 1. Change the engine oil and filter per manufactures specifications and oil volume. Run the engine for 1 minute. Shut off engine for 1/2 hour. Check oil level on the dipstick. MARK THE OIL LEVEL WITH A METAL FILE on the dip-stick & clean before replacing in the engine. This is the "cold" oil level full mark.
2. Now run the engine up to full operating temperature (abouth 1/2 hour). Shut off and immediately check the oil. Mark this line with a metal file. This is your hot oil mark.
When checking your oil pull, and wipe the dip-stick first. Then, check the oil level, twice. Know and understand the difference.

[TideTime]

The overfilling of your Yanmar diesel crankcase with engine oil can be just as harmful as underfilling. Although modern diesels may not be as susceptible to the so-called "runaway" condition as older and poorly maintained diesels (eg. worn piston rings), contrary to some opinion, the diesel does not have to be turbo-charged to incur this condition. Your diesel engine will run all too well burning oil as opposed to diesel fuel and under certain circumstances could result in catastrophic engine failure.