The oil change blues.......

[Bob Rutland]

Everytime I change the oil in my Yanmar 2GMF, I can never seem to get all the dirty oil out. I'm using a hand pump through the dipstick hole and replacing the filter. I then add the new oil, check the level,and the oil looks great. Then I crank the motor, shut it down, and recheck the oil level. The oil is black like I never changed it.What can I do different?Thanks, BobS/V H31 "Lady Di II"

 

[Steve Dion]

Are you getting it all?

Bob:These engines only hold about 2 qts/liters of oil. You should try measuring the amount of oil that you remove before you refill. Also be sure that you run the engine before you drain it. This will get the oil warmed up so it will flow easier. The engine is tilted aft so you do need to get the pick-up tube as much aft and into the bottom of the pan as possible.As we know the oil on a diesel does get black quickly.

 

[Eric Lorgus]

Steve's right - the engine needs to be hot!

Bob: I've tried changing the oil on my Yanmar 2GM20F with both the engine warm and the engine hot. It's a world of difference!I use a vacuum tank. When I tried with the engine merely "warm", it took forever to pump out a small amount, and what came out moved at a snail's pace.Next time, I made sure the engine was hot (since the engine had already been winterized, I heated it by pointing an electric space heater at it for 45 mins, which got it nice & toasty). With the engine hot, the oil raced out, and it was easy to scavenge out the residue by working the pickup hose in & out slightly after most of the oil was out.

 

[jamie]

oil

Hi Bob i might be to finicky but i change my oil very often and when i do i sacrifice a qt. by hand pumping out the old and then pouring in a qt of new and sucking it out it seems to be the only way i can get it clean looking on the stick and for the price of a filter and a extra qt of oil i fiqure it is the cheapest maintainace i can do on my boat

 

[Gordon Torresen]

Cleanliness is relative

Three good responses previously. Hot oil pumps more easily. A flush will help. However, when you look at the entire act of changing oil, you will see that what you remove is only that oil on the bottom of the pan. Suck as you may, you dont get the dirty oil that is in the oil galleries or just hanging on all the surfaces that are not the bottom of the pan. In fact, if you were to remove that pan, you would be surprised at what is left. When you put in your new oil and start the engine, you immediately mix the new with some old from the oil pump, crank shaft and internal oil passages. The new oil now looks black. A thing to try is to put a drop of the old oil and a drop of the recently changed oil on a light colored surface and compare the two. I'm sure that you will feel a lot better about what you have done. You might even save a quart of oil.

 

[Greg Ketley]

Oil is cheap

I may be alone, but I always change the oil twice once I am at it. It only takes a few minutes longer and very little added expense. Makes me feel better for a couple of bucks.