Octane for 1990 90hp Johnson?

[ineedacottage]

Hey guys,

I did a search, but I can't seem to find the answer to my question. I bought my boat about 7/8 years ago from the original owner. He said he had always ran premium gas in the motor, so I continued with this.

Now, after seeing a few others posts concerning this and stating that only regular or mid-grade should be used, I wonder if I should use one of those instead, even if only premium has ever been used in my motor?

Thanks a bunch for your help.

 

[iwombat]

Re: Octane for 1990 90hp Johnson?

The higher the octane, the more ethanol it's going to have. Ethanol is bad news for lubrication. Stick to the cheap stuff and your motor will be happier.

 

[PondTunes]

Re: Octane for 1990 90hp Johnson?

I have a 90 Hp Johnson about the same year, 87 octane all day long, you shouldn't notice any drop in performance.

 

[ineedacottage]

Re: Octane for 1990 90hp Johnson?

So the fact that only premium has ever been used is a non issue?

Thanks a lot guys!

 

[GlasV162]

Re: Octane for 1990 90hp Johnson?

I have the same motor, except it's an Evinrude. I've always heard premium gas is best due to the higher compression of a 2-stroke. Yes? No?

 

[Kevin W]

Re: Octane for 1990 90hp Johnson?

There where a few 2 strokes that had a little higher compression .
If my memory serves me correctly it was mercury tower of power 6 cyls.
and high test was reccomended for it.
There is no need to use high test gas.

 

[jglad]

Re: Octane for 1990 90hp Johnson?

Here is the link to some interesting information I found on the Evinrude website:

http://www.evinrude.com/en-US/About.Us/FAQ/Oil.Fuel.htm