How long does fuel last?

[PeteOOXXOO]

Hi Crew. Spring has sprung here in Australia and we are hitting the water this weekend - first time out since May. Just wondering whether I should be concerned about the age of the fuel? We only had the new boat for a month or 2 before last season ended, and we always use Premium unleaded (minimum 95 octane) - there is about half a tank left.

Should I drain it somehow or if I top it up with new Premium will it be ok?

Thoughts??

[jkendallmsce]

Next year, use STABIL in the fuel, it will help keep it from becoming varnish...add a can of injector cleaner and fill it with fresh gas to mix with the stale gas...it'll be fine

[CliffB]

You'll be fine. Top it up with fresh gas and it should be OK.

If you have injection rather than a carb it will be a bit more sensitive to condition/age of the fuel - a carb is usually a bit more forgiving. But in any case, if you top it up with fresh you should be fine either way.

[REW]

+1 on the staybil for the winter layup, get some good injector cleaner and go bording.

[Woodski]

I would suggest you google "fuel storage" and similar topics along with going to a Shell/BP/Esso etc website to get expert feedback to your question. Generally correct, adding 50% new fuel to the existing amount will help. The octane rating will be lower than when filled, the formula might not be the correct one if down under the fuel companies adjust the mixture for temperature changes as they do in the USA and the light end hydrocarbons have long since joined the rest of the atmosphere. The RVP has changed so starting will be harder than normal, but probably not something that will be problematic as I assume you are not at a temperature extreme right now.

[PeteOOXXOO]

Awesome - thanks for the help folks