Changing the oil on Yanmar with suction pump

tudorsailor

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Having been sailing continuously for three months (a sabbatical) I had to change the oil on my Yanmar. This is not something I had done before. I was equipped with a Pela 650 oil extraction pump. I put the smaller tube that comes with the pump down the dipstick tube and pumped. I got about half of the oil out. The supplied flexible tube does not go to the bottom of the dipstick tube it seems

I then learned that the technique is to put some tubing OVER the outside of the dipstick tube and connect that to the suction tube of the pump. Apparently one has to make sure that the tube goes right down to the shoulder on the top of the dipstick tube to cover the little air hole.

Once this was done I pumped out oil the oil.. In spite of the engine apparently holding about 7L I got 5L out but was assured by the Yanmar mechanic that I had on board that I had done this correctly and all the oil was out

How do I learn these tricks in future without asking an expert and looking a fool? There needs to be a book of tips and tricks for maintainance

TudorSailor
 
Having been sailing continuously for three months (a sabbatical) I had to change the oil on my Yanmar. This is not something I had done before. I was equipped with a Pela 650 oil extraction pump. I put the smaller tube that comes with the pump down the dipstick tube and pumped. I got about half of the oil out. The supplied flexible tube does not go to the bottom of the dipstick tube it seems

I then learned that the technique is to put some tubing OVER the outside of the dipstick tube and connect that to the suction tube of the pump. Apparently one has to make sure that the tube goes right down to the shoulder on the top of the dipstick tube to cover the little air hole.

Once this was done I pumped out oil the oil.. In spite of the engine apparently holding about 7L I got 5L out but was assured by the Yanmar mechanic that I had on board that I had done this correctly and all the oil was out

How do I learn these tricks in future without asking an expert and looking a fool? There needs to be a book of tips and tricks for maintainance

TudorSailor

some of the 7ltr would have still been in the filter
 
I came across this discrepancy recently as the engine book stated 7 litres at zero degrees and 5 litres at 15 degrees. I think it depends on the angle the engine takes when fitted. Am fully prepared to be shot down.
 
Dunno why your tube didn't reach the bottom of the sump. Mine was well over-length, and in fact I cut quite a lot off when some debris got stuck in it (hoovering out the engine bilge) and it was still long enough.

I'm surprised you were able to suck all the oil out using the dipstick tube itself; I assumed this just entered the top of the sump but didn't reach down to the bottom.

As for how you learn these things - easy, ask on here :)

Pete
 
It may be that boat engines work differently, but in car engine land, a dipstick pump is not well regarded, as it doesn't get the sludge that accumulates at the bottom of the sump, whereas draining through the sump plug will flush most of it out...

Do yanmars not have a sump plug because of the difficulty of access or something?
 
It may be that boat engines work differently, but in car engine land, a dipstick pump is not well regarded, as it doesn't get the sludge that accumulates at the bottom of the sump, whereas draining through the sump plug will flush most of it out...

Do yanmars not have a sump plug because of the difficulty of access or something?

They do have sump plugs but they are usually difficult to access and even if you could, the hull or engine mounting frame would make capturing the flow of oil impossible.

Decent oil and a pump driven filtering system would normally mean no sludge by the way.
 
I then learned that the technique is to put some tubing OVER the outside of the dipstick tube and connect that to the suction tube of the pump. Apparently one has to make sure that the tube goes right down to the shoulder on the top of the dipstick tube to cover the little air hole.



TudorSailor

I'm trying to visualise this. Can you (others) explain a bit more. I'm about to do similar.
Thanks
 
They do have sump plugs but they are usually difficult to access and even if you could, the hull or engine mounting frame would make capturing the flow of oil impossible.

Decent oil and a pump driven filtering system would normally mean no sludge by the way.

The Yanmar service manual only mentions removal of oil via the dipstick.
 
I measured the diameter of the outside of the dipstick tube. I then bought some clear plastic hose that was about 1mm bigger. This meant the internal diameter was a bit smaller that the diameter of the dipstick tube. Once enlarged it made a nice tight fit over the dipstick tube. The dipstick tube has a shoulder and it is important that your plastic tube goes right down to the shoulder. In that way it covers a little breather hole that would otherwise stop your vacuum pump from sucking!

I then took the end off the tube that is meant to go down the dipstick tube and used the end to bridge my plastic hose to the tube that goes to the suction pump.

I am no longer on board so cannot help with photos

Does this help???

TS
 
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