Originally Posted by hellosailor
Contact the stabilizer maker, the products are all different.
Stabilant (for gasoline) says it is good for up to two years. That would imply replacing any that was more than two years old. Enzyme treatments are biologics and I'd expect them to break down as they age as well..
I know it was a stupid thing, but we moved our boat down the coast a couple of years ago and - due to a house rebuild
that took priority - left the gasoline in the built in tanks for two years. It had marine
Stabil in it, and the motors worked fine every month or two that we used them. And then they didn't. And it was bad. Carb cleanout, then about 30 minutes of run time, then carb cleanout, etc. The gasoline looked like a horrible piss yellow. I have full size 10 micron filters on each tank, plus strainers, and water
separators. The gas looked all one phase. After the carbs were cleaned, the motors ran fine. Then started sputtering until cleaned out again. Or if put away still running good, would not run when we came back.
Ok the point is not how stupid I was, but what I did about it. I consulted an outboard mechanic
that I have found to be an expert in his field. He recommended draining the tanks. I purchased an electric fuel pump
from an auto parts
house, some clear hose, and pumped out the gas into plastic gas cans. A friend wanted it and it burned fine in his truck. (So I didn't have to find a place to dispose of 20 gallons) I put a long cord and a cigarette lighter plug
on the pump. After that, I purchased ten gallons of ethanol free gas, stabilized it with QuikStor (Mercury product), and added 16 oz can of SeaFoam. Put this into the 15 gallon permanent tank. Changed out the fuel canister filter, then hooked up the electric pump
to the system and circulated the mixture thru for about an hour. It was a 35 gph pump, so probably circulated thru twice. The SeaFoam hopefully cleaned the system. Then changed out the canister filter, and cleaned the carb. Did the same for the second tank and motor
So far have run thru 30 gallons of gas - on a 200 mile run up the ICW
- and the motors have performed flawlessly. Outboard mechanic
also told me NOT to run the gas out the carbs before putting up/storing the motors, as this still left a small amount of gas in the bottom of the carb that will eventually evaporate and leave residue in the carb.
I should have less problems now as we are no longer running ethanol gas (can get it in Corpus and a few places nearby, as well as I understand it is available in Florida
- as there and the Bahamas
is where we head
next). And its stabilized. And I will be replacing what is left at the end of the year. It's a sailboat with 30 gallons of fuel capacity, and except for ICW
trips when offshore
is crappy, we only burn about 10 gal per year.