I just aquired a boat with a '90 Mariner 150 on it ant it requires pre-mix. This is my first big boat that requires a pre-mix (the others had oil injection). I need advice on the correct way to get the 50:1 mixture right in a big gas-tank.
Hey Astro....Welcome to the forum.<br /><br />50:1 mix equates (big word) to 16oz of oil to six gallons of gas. So....if you got a 12 gallon fuel tank, add 32oz of oil BEFORE adding gas. This is to make sure the brew gets all mixed up real good. Enjoy the water!!
I like to do it is a 6 gallon gas can myself, I just a little paranoid about stuff like that. I add the oil and then the gas and shake. Then I pour it in my boat. I do it like that so that I can not over oil or under oil if there is already gas in the tank of the boat.
The manufacturers all recommend that you have the right amount of oil ready for the amount of gas you're going to put in and then sort of meter it in as you fill the tank with gas. This assures proper mixing. In practice, however, I've always done it like OutboardJim and just put the oil in first. In over 50 years, have never had a problem from doing it this way.
If you purchase a premix bottle, there are different ones available. With mine you have scales on the side for many different ratios, 20/1 25/1 32/1 40/1 50/1 etc. and is listed for liters, and gallons. It is a tall white semi-transparent bottle. You put your gas in the tank, pour oil in the bottle to the appropriate scale for mix/gal(litre), pour that in tank, and shake up if in a gas can or small tank. If it is a large built in tank, trailering, or wave action as noted previously will mix the brew very rapidly with a little movement.<br />Walt
One other way to do it is to take a small empty can along with you when you fill up your boat. Begin by putting some petrol (gas) in the small can then fill up your tank leaving enough room for the small amount of gas in your can to be added. You will then know exacly how much new fuel you have added in total from reading off the pump. Using one of the premix measuring jugs that lakeman talked about, add in the oil for the total amount of fuel, shake and then add to the boat fuel tank. <br /><br />The benefit of doing it this way is that your oil is mixed with fuel before being added and should mix in easier when added to your main tank. You also know exactly how much oil you need to add because you know how much fuel you have put in.<br /><br />Just a thought.<br /><br />cheers - T
