I need some help,my grandpa bought a 5hp johnson 2 stroke in 2000 and its sat untill now in the box checked it out yesterday and

[Trip55]

I need some help,my grandpa bought a 5hp johnson 2 stroke in 2000 and its sat untill now in the box checked it out yesterday and looks good.I wonder if anyone knows the ratio to mix the gas. Thanks

[Quinton Schmelzenbach]

My history working with boats in Fiji, and a little bit of research, is telling me 50:1.
So that would be: 1 Pint oil to 6 gallons of gas.
(400ml/20 liters)

[Hoski]

Quinton nailed it...50 to 1.

[jhjimbo]

I would think 40:1 would be safe. Also, use the latest 2 stroke oil, for Johnson i believe it is TWC III. That oil has the best additives for mixing with the fuel and fighting corrosion. If you get gas near a marina you may find it without ethanol which is the most desirable. Otherwise you might consider Stabil-ize product specific for marine use that prevents the corrosive effects of ethanol.

[DSMbirddog]

Did you check the box for an owner's manual? If not you can find one online. Quinton is correct and do use TWCIII oil as Jimbo points out.

[jay]

Good advice from above, ethanol is horrible in boats unless you are using the boat all the time. Most of us are not that fortunate.

[Treestand]

Get you some Non Ethanol Gas at you local Marina its about $4.00 Per Gal. and a good Syn-outboard motor Oil.
the Mix would be 50-1..for a 5Gal fuel tank.

[Ontario Honker Hunter]

The key here is how old is the motor? You said he bought it in 2000 but you didn't say if he bought it new. I PRESUME it was new that year and if so it's definitely fifty parts gas to one part oil. Five gallons of gas would require 1/10 gallon of oil or 8/10 of a pint. You can guesstimate this amount.

[santa]

Jay hit the nail on the head. Ethanol is not recommended for the older two strokes. If the motor is new, it needs a break-in period. During the first tank of fuel, I would go with 24 or 25 oz. of oil for the first six gallons of gas, then back to 16 oz. for six gallons on the second tank and thereafter. The fixed jets in the carburetor were not set for the extra oil on the first tank, so do not expect the motor to idle as well as it will after the break-in tank of fuel. After setting up for so long, I would let the motor run for a while at fast idle and check to make sure that it is pumping water properly and staying cool. Then follow a good break-in procedure of not running the motor at any one speed for a long period during that first tank.

On a side note, Back in the fifties and mid-sixties, 25 to one was the recommended oil to gas ratio. This was probably because of the the quality of the oils most people used at the time. Many people just mixed 30 wt. non-detergent motor oil in the gas. Then 50:1 oil became a standard for outboards, even the earlier older models because specific water cooled two stroke oils became so widely available and were much better. Then again about thirty years later, newer oils and better manufacturing tolerances of motors allowed the use of 100:1 mixes. Even though this worked well with new gas, if the gas set for a while and was allowed to degrade, it was found that the 100:1 mixture "may" not be adequate. So 50:1 is the safe way to go and always try to use new gas that is fresh mixed if possible.

[bruisedsausage]

Don't start with 50:1 if its never been run before! Start with a rich mixture. More appropriately about 25:1 and then lean the mixture out after the motor has been run for 20-30 min on the rich fuel. Change your plug at the same time too.

[Pray- hunt-work]

50:1 is correct for an already broke in motor, the break in procedures above are just right. 50:1 is twice the oil that 100:1 is if you're not familiar with mixing fuels. Although you can have too much oil, more is better than less. If you are to mix it 25:1 during break-in you'll notice that it smokes more. That's simply the extra oil burning off and coming out the exhaust in the smoke form. The only repercussion to burning a little extra oil, as stated by bruised sausage, is fouling plugs. Not a big deal at all. I also recommend that if your mixed fuel is going to sit dormant for any period of time, you add some type of fuel additive to prevent the fuel from breaking down. Startron makes a product called Marine Sta-bil which I highly recommend, but is not needed if the tank of fuel is to be used with a two week time. Best of luck & enjoy!

[Trip55]

Yes the motor is brand new I pulled the receipt of the box, yesterday it was made in 2000 and was bought from the dealer. There was no manual with it in the box. I will run a little richer fuel in it to start, I apprciate, the help always can rely on Field & Stream guy. Thanks

[santa]

Trip55, as I said earlier, make sure the water pump is working properly. The rubber impeller in the water pump has been setting for 13 years and is subject to some possible degrading over that long of a period. The vanes (fingers) of the impeller sit eccentrically in the water pump housing so some of the vanes have been bent tight in the same position long enough to have taken a set. Also check the gear oil level in the lower unit before you start it.