Oil consumption on modern 2 stroke

[Linnhe Lascar]

Looking at various boats and weighing up 2 stroke v 4 stroke

My first ever boat (Orkney Strikeliner) came with an old 2 stroke (this is about 15 years ago) and after a year I swapped it for a Honda 4 stroke. Main reason was the nuisance of what you had to do to monitor the oil level and top it up; you had to take the cover off, look at the little oil tank to check level, fill it if needed and get the cover back on, all of which was a PITA while at a swinging mooring.

So for that reason I intended to buy a rib with a 4 stroke, but am now seeing some nice boats with modern 2 strokes (usually Optimax)

Question: how much oil do these modern engines burn? How often do you have to top up the oil? How much of a pain is it to do? Is there an external gauge or something which lets you check the oil level without having to take the external cover off the engine?!

All help gratefully received

[gotchiguy]

Originally Posted by Linnhe Lascar

Looking at various boats and weighing up 2 stroke v 4 stroke

My first ever boat (Orkney Strikeliner) came with an old 2 stroke (this is about 15 years ago) and after a year I swapped it for a Honda 4 stroke. Main reason was the nuisance of what you had to do to monitor the oil level and top it up; you had to take the cover off, look at the little oil tank to check level, fill it if needed and get the cover back on, all of which was a PITA while at a swinging mooring.

So for that reason I intended to buy a rib with a 4 stroke, but am now seeing some nice boats with modern 2 strokes (usually Optimax)

Question: how much oil do these modern engines burn? How often do you have to top up the oil? How much of a pain is it to do? Is there an external gauge or something which lets you check the oil level without having to take the external cover off the engine?!

All help gratefully received

They won't burn half as much oil as your old 2 stroke, and evinrude etecs burn even less oil thank Optimaxes.

It depends on the size of the engine, I think the Optimax 115 have the oil tank under the cowling but there is a cap you can use to fill it up without having to take the cowling off. Above that you have an external clear plastic tank so you can clearly see the amount of oil remaining and top it up. With the etecs there is an electronic sensor in the oil tank which tells you when it is low and you need to top up.

[Nos4r2]

There's big remote oil tank on my 225 opti. It's less of a pain to top up than it is to manually check the oil level on a 4 stroke.

[Linnhe Lascar]

Thanks chaps

I'm trying to get a sense of how often you have to refill the oil. If you've got a main fuel tank of say 100l, do you have to refill the oil about every time you empty the petrol tank? Or every other time? Or every five times?! Or what?

Sorry to be a noob!

[gotchiguy]

Originally Posted by Linnhe Lascar

Thanks chaps

I'm trying to get a sense of how often you have to refill the oil. If you've got a main fuel tank of say 100l, do you have to refill the oil about every time you empty the petrol tank? Or every other time? Or every five times?! Or what?

Sorry to be a noob!

Depends on the size of the oil tank...a small tank ~1.5 gall probably once every other fuel fill, a big tank ~3.8gal, maybe only once ever 4 or 5 times

[Nos4r2]

Find out the size of oil tank for the motors you're looking at specifically.
They burn less oil than a 50:1 mix, so if you work it out as 2 litres of oil to every 100 litre tankfulll, you'll get an overexaggerated consumption and you'll fill it less than that.

Etecs have more variable usage rates depending on what oil they're programmed for, but shouldn't use more than 50:1.

[two stroke mick]

I have a 60hp etec and I would put in about a cup full for a two - three hour spin. I top it off after every use not required but force of habbit and one less thing to think about. But in reality I would only need to top it of after every use. If I recall correctly the tank on the etec is good for 10 hrs (XD 100).

[Pikey Dave]

The 115 & upwards Etecs have remote tanks. On the Oban trip I used about 1/3 of a tank of oil per engine & we did around 370nm, not bad going in my book, the tanks are 1.8us gal. It works out at around 75:1. The modern engines vary the amount of oil depending on the engine load. At tickover Etecs use around 0.7l/hr of fuel & virtually no oil, hard acceleration or overpropping increases the oil usage, steady cruising will return around the aforementioned 75:1 when on the XD100 setting.

[willk]

Running Etec 90s at lowish revs (3500) I was returning averages of better than 100:1 on XD100

[Linnhe Lascar]

Cheers all, much appreciated