Oil level on 4-stroke

[Ribald]

The weekend before last (and, I'm afraid to say, for the first time since we got the boat) we checked the oil level (cold) in the sump of our Suzuki DF115 We found that the level on the dipstick was well above the "Full" mark on the dipstick We then bought one of those Vacuum Oil Removers to remove 2L of oil which bought the level down to the upper mark on the stick.

After this w/e's outing we checked the level again (hot) and found the level was up once more. During both times of checking, the engine was in the "down" position and on the trailer in the same location in the boat compound. The oil on the stick was quite clean with no signs of water in it and no signs of emulsification under the oil filler cap. Are these engines known for erratic dipstick readings or have we go an oil-producing lump ? I suppose the only real way we know how much oil is in the sump is to drain it out and put back in the required amount - 5.5L

[Neil R]

I've got a DF90 which I think is the same basic lump.

On it's two oil changes so far, after draining the oil I've poured in a full 'normal' sized oil containers worth (presuambaly 5L, I can't remember, but definitey less than 5.5L) thinking I'd then top up with a smaller 1L bottle after checking the dipstick. On both occasions, however, this initial pour ended up significantly overfilling according to the dipstick.

Like you I've spent some time trying different tilt angles - but I couln't find one which make it look less over-full (if you see what I mean).

The obvious question for both of us is whether to go with the dipstick or the manual?

I've gone with the dipstick so far, but that's purely because I had a very bad experience with an over-filled ford escort many years ago!

[jwalker]

I know nothing about your engine but I've seen sump contents increasing. Petrol pump diaphagm leaking. Petrol passes through the diaphragm and into the crankcase. You may or may not have this type of pump.

[nickjaxe]

I will 2nd what JW says.

Nick.

[avanti]

As any other liquid oil expands with temperature, and depending on whether the the engine oil level should he checked cold or warm it could differ quite a bit.

Dry sump engines should almost always be checked warm, sometimes with the engine running, sometimes right after cut off.So first I would find out when/at what temperature the engine oil level should be checked.
Most outboards are dry sump aren`t they?

My experiences on dry sump are based on cars not boats.But should be pretty much the same.

[Scary Des]

There was an issue with some engines where the bung on the dipstick could move up the dipstick if used ‘aggressively’, resulting in an apparent increase in oil, but this is only a remote possibility. I think that what JW is saying could be a real issue.

Incidentally did you de-winterize the engine before use? Some people virtually fill the sump when winterizing the engine.