Yanmar 3JH, Oil change, dipstick or service manual quantity?

[dial_amonkey]

Beneteau Oceanis 40 2009, Yanmar 3jh43 @ inclined 15%

Hi everyone, I'm a little unsure if I should I use the factory dipstick mark or the Service Manual Oil quantity for amount of oil to replace when changing the oil in my Yanmar 3jh43e and would appreciate any input, ideas or advice of how to work out which is right.

When I fill to the manual specified 5 liters, it shows around 300-400 ml over the high mark on the dipstick

I pump out around 3.8 ltr of old oil with the dipstick at 1/2 full (using the dipstick tube) - I presume some remains, the dipstick tube does not suck from the very bottom of the sump.

I measure the oil level with the engine cold the next day, I pull the dipstick wipe, leave tube open for say 15 seconds slowly reinsert, wait 30 seconds, measure, try again until I get consistent results (I have read all the posts regarding the Yanmar dipstick). I also have compared the level by just sitting the dipstick in the tube - not pressing the seal in and then adding the seal distance to the measurement, reading the level from the front face of the dipstick.

The engine is a factory install at 15 degrees inclined, but I would expect the mark is right on the dipstick.

I've tended to settle the level at the absolute High of the dipstick knowing there's 1ltr between H and L.

[dial_amonkey]

There are references to a post " how to not 'overfill your yanmar' with oil when you are changing the oil ' but I have not found it - Thanks

[desodave]

My previous boat had a Yanmar 3jh4e with an installed pump for oil changes. It always drew less than the engine capacity even after accounting for oil in the filter ( and spilled removing the filter ). Similar with the subsequent fill, always less than engine capacity, including what went in the new filter before installing. I suspect your supposition is correct ... that some oil remains in the engine.

[chrisr]

if your dip stick is reading full...and you remove 3.8 litres of oil...and then put in 5 litres of oil...what do you expect the dip stick will read ?

fyi there is always some old oil remaining. you really need to minimise this (thats why you are changing the oil) but you'll never get it all. i've alwasy found an electric vacum pump does the best job but other will swear by manual pumps.

anyway, remove as much as you possibly can. then fill to high level on dip stick. then run motor for 10 mins or so. then let oil level settle and re-check. top up as required.

what the manual says about oil capacity is academic

btw : i usually overfill my yanmar oil level...sometimes 1/2" past high mark. never had the slightest problem

cheers,