I have read the seafoam stuff on the forums, and it always says to add to a gallon of premix. I have a 1990 40HP VRO Evenrude. Do I just add it to a gallon of raw un-mixed gas instead?
Weel I ran the Seafoam in the 3/4 gallon of gas thru it, and it seems to have improved (or more likely fixed) the rough idle problem. I also MAY have picked up a couple of MPH on the high end. Can't be sure because the I was running it on the river and between the current and the high winds it was not a certain thing, but I am getting 30MPH instead of 28MPH as a top end. Boat is a 15ft flat bottom LOWE bass boat with a 1990 Evenrude 40HP.
Actually, I put a pair of old plugs in for the de-carb and then replaced them with the original (fairly new) plugs. Surprisingly, the old plugs ran OK, but they were a wee bit on the black side.
