Draining oil out of the 3YM30

Steamboat_Willie

Active member
Joined
Nov 27, 2008
Messages
28
Fluid Motion Model
C-24 C SE
Vessel Name
Steamboat Willie
I'm chaning the oil in our 21EC for the 1st time since we took delivery in April 2008. Didn't use the boat all that much last season. I'm using a simple brass utility pump (JABSCO) to draw off the engine oil and when I insert the smaller diameter plastic tube down into the dipstick hole and begin pumping it seems that the pump is unable to suck out any oil. It's as if the end of the tube has bottomed out and something is preventing oil from entering the end of the tube. However I noticed that when I slowly pulled the pumpout tubing up and out, at some point (3 inches up or so?) oil then begins to pump and emerge. When all was said and done it seems like I managed to draw out about a little more than a quart. (thought there would be more.)

When I reinserted the dipstick it showed just a tiny drop of oil at the very end of the dipstick, just beyond that lower level indicator "hole" on the dipstick itself. So I figured I was done with removal of the old oil. I then replaced the oil filter, and added about 1.5 qts and subsequently the dipstick indicated full. However what bothers me is that the color of the oil on the dipstick still looked rather dark and not that "clear" brown that I would have expected from clean replacement oil.

So, my question is: Did I remove ENOUGH oil? If not, then HOW can I get ALL the oil out? Should I be using a different pump? Do I have a mixture of half dirty old oil and half clean replacement oil in the engine now? This was a simple procedure on our old sailboat which had a similar 2 cylinder Yanmar. And why am I experiencing what sure seems to be a problem when trying to draw out the oil when I insert the pump tube ALL the way down the dipstick tube? Is it hitting something? Is it creating some inherent vacuum down there that is preventing the removal of the oil? Something just doesn't seem right here. I figured I would post this question. Can someone comment from experience regarding this maintenance task on that engine?
Thanks.
Ed
 
I use a vac pump from harbor freight and I did have my fair share of problems however it does go to the bottom and make sure the oil is warm first or you will spend all day doing a change. I changed the clear hose and used air brake hose that
was stiffer. I forget now but it was like three quarts and check the book to make sure. The transmission uses very
little oil and i used the metric to figure how much as was easier. Bob Heselberg Eatonvile Wa
 
The O.D. of the tube that I was using to reach "bottom" was no more than 1/4 inch. It was quite rigid. I tried two different pumps actually. I tried the manual hand transfer pump first and then an electric home-brew gizmo that I fabricated from an old 12V Dupre fuel pump. (usually works like a charm!) Both vacuum pumping devices exhibited the same problem when the tube was inserted below a certain point in the dipstick tube. It's very strange. Like the end of the drawout tube was suddenly plugged. The oil was NOT warm however. Maybe that was the problem. I'm going to try again during the week (with WARM oil this time) and see if I achieve any better results.
Thanks.
Ed (N2TE)
 
I called a local Yanmar wholesaler (Mack Boring, very nice people) here in NJ this morning and they were very helpful. The service tech support fellow told me the following regarding the 3YM30:

1. The dipstick tube, as it goes down and enters the oil pan, makes an abrupt 90 degree bend. Thus it's not possible to insert a plastic drain tube ALL the way down to the bottom of the oil pan. Subsequently it wouldn't be possible to withdraw all the old oil in this manner. (this is what I experienced)

2. The service tech recommend taking my hand transfer pump that I'm using and placing the rubber inlet fitting over the OUTSIDE of the dipstick tube and using the dipstick tube itself to suck out the old oil instead of an inserted plastic tube.

3. The service tech also recommended that after I've withdrawn as much oil as I possibly can out of the engine in this manner that I reach under the oil pan and using a 16mm socket remove the oil drain plug on the bottom and allow any remaining oil to exit. Because space is obviously limited under the oil pan, he suggested that I merely take a small plastic garbage bag and use that to catch the remaining leftover oil as it drips out of the oil pan. Then the bilge won't any get oil in it.

4. Since the owners manual says 2.6 qts, dump in 2 quarts of clean oil into either of the oil fill ports and then run the engine for a few minutes. Then using the dipstick fill marks add any additional oil to reach "full".

Sounds like a reasonable plan. For someone like me who is not all that experienced working on engines this information was quite helpful. I'll try that and will post my results.

Ed
 
Hi,

Thought I would add a little something I found on my engine, 3YM30. A few weeks ago, I changed my oil and filter. I used one of those oil pumps/tank things as well. It has a stiff Teflon? type tube. Anyway, I was able to insert it into the dipstick tube until it was able to draw oil. About 2 quarts was drawn through this opening. While I waited for the oil to pump out I went ahead and changed the filter. I found on the side of the block, below and forward of the filter something that looked like another dipstick, but painted to match the engine. Since it was rubber, the paint flaked off almost immediately. It looked more like the rubber part of the dipstick with the loop section cut off. I pulled that out and was able to put my drain tube all the way to the bottom of the oil sump. I was able to draw the sump practically empty. Very little oil remained in the sump at this point. Not enough to worry about pulling the sump plug.

If all went well, I have attached a picture indicating the location this plug.



Hope this helps,

Bri
 
Well it looks like the advice of the Yanmar support fellow was right on the money. It WORKED!

I attached the rubber fitting on the inlet of my hand transfer pump over the outside of the top of the dipstick tube and then just started pumping away. Wow! 3 quarts of oil came out real quick. It was VERY easy. Looks like that's the trick to making this task easy to do. And that little brass Jabsco hand utility transfer pump that I've been using works just great! I did not bother opening the drain plug on the bottom. I poured in 2.5 quarts of clean oil and will run the engine later this week when I have time and check the oil level and see where it's at. I'll jot this one down in my maintenance manual notes for future reference. Hope this will help others. Ya' learn something new every day.
Ed

(Bri, thanks for your reply. I'll make a note to look for that other entrance point which you've mentioned. Thanks.)
 
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