The required mix is 24:1 but you have to read the manual carefully as it says one quart of oil to a full tank of gas, which is six US gallons. That makes a 24:1 mix but further on the manual says ‘for ease of measurement’ to mix one half pint of oil with one gallon of gas, which is for smaller amounts. I’m assuming the company figured it was easier for the average Joe to measure out a half pint instead of one third of a pint of oil. This would allow for a bit of error on the users part to protect the motor in case in case they didn’t measure out enough oil.
Hello. I often wonder what it meant to a full tank of gas. Because you have 6 gallon tanks and the 5 1/2 and ten horse motors usually used a 4 gallon tank.
All my QD manuals and marineengine show a six gallon 375774 tank for the ten horse motors which is the same one used for the eighteens. The ’55 QD-16 parts manual also shows a straight foot valve in the tank while the foot valve in the small tanks was bent to fit. Seems like it was only the 5.5 and 7.5 horse motors which came with the small tank. Either way, a quart of oil in a full correct tank for a motor will give either a 16:1 or a 24:1 fuel mix. This only works for US gallons and not the old Imperial gallons.
.
