2 stroke mixture ratio

[Vic.S]

I've spoken to the previous owner and he said he always ran the outboard at 100-1

If it is a Genuine OMC made model then that is almost certainly wrong.

Only 4 strokes are listed on the parts website for 2002 which of course no not use oil in the fuel but can easily be recognised by having an engine oil reservoir with a dipstick or sight glass and often a camshaft drive belt

However 2002 is about the time OMC went out of business and BRP took the brands over. At about that time rebadged far eastern made models were introduced.

Belgium made models for the European market sometimes do not appear on the US based parts websites or are slightly different from those that do

Firstly you need to be certain whether it is a 4 stroke or 2 stroke. Oil level will have to be checked and maintained if it is a 4 stroke. it will also be vital not to lay it down incorrectly.

If it is a 2 stroke then 50:1 is always a suitable and safe mix for everything bult since the mid 1960s . It is also a sensible choice even for engines that according to the manufacturer are suitable for 100:1.
50:1 is usually recommended for heavy or commercial use even when 100:1 is the mix for " leisure" use

As soon as you can post the model number and if possible a photo or two showing the power head

 

[trikerpop]

I went to the boat on Monday but as the outboard is fitted on the boat I couldn't get close enough to see the model number on the plate as my eyes are not as good as they used to be. I could make out that it had OMC on it though, and no dipstick so definitely a 2 stroke. I added just 2.5 litres to the tank which made the mixture 75-1 and it ran fine.

 

[racerone]

Of course it will run fine on 100:1 or 75:1---------It will not run for as many hours as when it is run at 50:1 as per the design of it.

 

[V153]

Yes. It should be 50:1. Think I'd run it at 40:1 for awhile to try'n make up ...

 

[gm280]

It sounds like the oil mixture has zero to do with your initial problem. It actually sounds like you need to open a vent in your tank all the way so it doesn't starve for fuel and die. I think you're confusing yourself with the mixtures when the tank was the problem... Just my take on it and easily could be wrong, but it sure sounds like starving for fuel and when you used somebody else's tank of fuel, it run fine... Check you tank's vent!

 

[V153]

6 gals is approx 23 litres. We add 16oz of oil. Which is a lil under half a litre.

 

[caliber]

Never run lean on the oil any thing over 50:1 is not good. I run all my motors fat 40:1 or even 32:1 if its not fauling plugs its better for it. Never ever ever 100:1 unless u could use a extra anchor in a couple months

 

[racerone]

Triker----Please do a little bit of research on 2 stroke engines and the concept of mixing gas and oil.---Lubricating oil is continually introduced to the motor via the gasoline.---The motor will run very nicely on straight gas but not for long !!!!

 

[trikerpop]

Thanks again all for your words of wisdom. I'll put the other 2.5 litres of fuel in with another 100ml of oil and that will bring it back to 50.1 and make sure the vent is well open.

 

[Vic.S]

6 gals is approx 23 litres. We add 16oz of oil. Which is a lil under half a litre.

23 litres is 6 US gallon

16 oz is a US pint

there are 8 pints in a gallon, 48 pints in 6 gallons

therefore
1 pint in 6 gallons is 48:1 which is as near as makes no difference 50:1

 

[rolmops]

Just to make it simple,use 100cc per 5 liters of gasoline.