2GM20 oil change, could the existing oil be elsewhere in the engine?

UK-WOOZY

Well-Known Member
Joined
7 Feb 2015
Messages
1,152
Location
medway river
Visit site
So the engines use 2 litres, i used a normal vehicle hand syphon pump to extract the oil via the dip stick hole. i extracted the oil until the pump was sucking air. took the previous oil filter off and had no more oil came out of that location, but the fact it uses 2litres and there definitely isnt 2 litres extracted is there another location oil may have settled in the engine. thanks
 
There will be a fair volume in the oil filter but its common not to be able to extract the full volume from the sump especially if the engine is mounted on an angle.
 
I wouldn't worry about it. Just fit a new filter, refill with fresh oil, run it for a few minutes, turn it off, leave it a few minutes to drain, then check the dipstick and top-up as required.
 
I always found my 2gm 20 was the same. As said there is a bit in the filter. I always used a 2 litre plastic milk container but it was usually just over half full. I suspected it wasn't getting it all out of the sump despite my tube being in the dipstick hole as far it would go. I know it's a waste of new oil but it was cheap supermarket stuff anyway, I used to empty as much as I could. Change the filter pour in a litre of fresh oil, fire it up for a few seconds then drain it again. Then refill with new oil to the correct level.
 
I have just had one of these to bits and there is no dipstick tube, so you have to put the sucker tube down to the bottom of the sump. Even at a normal tilt back, there will not be much oil left, as the sump is not very long for & aft . Less than 20cm? and the dipstick is slightly aft of the middle. As for the rest of the engine, there is the gear case up front, but that drains to the sump. The sump does have the casting shaped to allow a plug, but this one did not have it fitted, so I drilled and threaded it. But it will not get any more out than sucking. Just might wash out debris, except the access in the boat is dire.
 
Always a pain, and one used to be able to get "flushing oil". The "new oil" is rapidly black even after 3 close timed refill/suck out procedures.
 
Modern oil filters have a non return valve in them so they remain full when the engine is off. Yours is probably still full even though nothing is running out of it.
 
The Volvo has an oil drain tube separate from the dipstick. I don't know the Yanmar, but presumably it doesn't have this?
 
Modern oil filters have a non return valve in them so they remain full when the engine is off. Yours is probably still full even though nothing is running out of it.

Although the non-return valve does not operate on the main oil feed down the middle of the oil filter so, if there is any oil in it, it will empty out of there when the filter is removed. :)

Richard
 
Same story with my 3GM30. I've learned to wiggle the tube round a bit to get to some areas of the sump that seem to hold a few mil more oil. But never get the amount out stated in the manual (nor put that amount back in) and new oil turns black within days. There might be horrors going on inside the engine (not helped by getting seawater in the engine twice) but it still pulls like a train
 
Top