Fuel for new Merc 150 4-stroke

[TomB985]

Hi everyone,

My parents recently bought a new '13 Glastron GT180 with the 150 HP Merc 4-stroke outboard. The dealer told them that they needed to run 89 octane in the engine and to run marine Sta-Bil in the tank. They asserted that if she didn't run the Sta-Bil the ethanol in the gas would mix with the water and turn into corn syrup.

I think he's selling snake oil.

The FACTORY says that 87 octane is required, is there any reason to run 89? I've heard that ethanol attracts water before, but I've never had any issues with it in my Larson. What do you guys think?

 

[JB]

Re: Fuel for new Merc 150 4-stroke

I agree with the Merc engineers, Tom. That engine was built about 20 years after E-10 became the standard unleaded regular. I am confident that it was built with running 87 octane E-10 in mind.

Marine Sta-Bil would do no harm, particularly if fuel is stored for extended periods.

 

[jasonbailey]

Re: Fuel for new Merc 150 4-stroke

Agreed on the 87 octane. I always put sta-bil in at every fill up. Sometimes I use my boat a lot and sometimes it sits for a bit. Sta-bil can't hurt.

 

[TomB985]

Re: Fuel for new Merc 150 4-stroke

Agreed on the 87 octane. I always put sta-bil in at every fill up. Sometimes I use my boat a lot and sometimes it sits for a bit. Sta-bil can't hurt.

Completely agree with you about Sta-Bil; I've used the product for the last few years with great success when storing engines for the winter. My issue was mainly that my parents were told that they will gum up their new engine if they don't use it, which is something I completely disagree with.

 

[ondarvr]

Re: Fuel for new Merc 150 4-stroke

Lots of hype, scare tactics and misconceptions about E-10, just run it, if you wish to run some form of stabilizer that's fine, but it isn't really needed, especially on every tank.