Bad Fuel?

Fuel can go off over time and I think premium has a lower shelf life.

First questions, what fuel is in it, how old is it and how much fuel is in the tank?

I must declare my hand first up, i am the national sales manager of the company that distributes Sta-Bil fuel stabiliser so i have a bit of knowledge on the subject of stale fuel.

regular unleaded starts to break down in about 60 days, high octane fuels it can be as little as 21 days. this will happen quicker the lower the fuel in the tank because the main killer of fuel is evaporation. The lower the fuel level the more air is present in the tank which speeds up the evaporation process. the different compounds evaporate at different rates which significantly changes the composition. It is the aromatic that evaporates the quickest which is what enables the fuel to ignite properly.

Using a fuel stabiliser in a car that spends a lot of time sitting around will prolong the life of the fuel for up to 12 months.

Anyway ... having said all that it is a preventative and wont fix the problem once the fuel is stale. Your only real option is the drain the tank and replace it with fresh fuel.

Once you get it running again add a fuel stabiliser and you shouldnt have the problem again.

Gareth

The brand doesnt matter so much, i was more asking about the rating used. If the tank is nearly empty you could fill it full with new fuel but then actually drive it and use the tank to clear it all through.

Just fresh fuel may not clean it up and there may be gum and crap in the carby and filter from the old fuel. Perhaps a new filter would be a good idea and you *may* need to clean out the carby but try fresh fuel first