To store with or without fuel?

[John90290]

I use my boat most weekends and after each use I would pull the fuel lines on the two Johnson 70hp 1977ish motors and run them out of gas with the logic being that fuel sitting in the carbs for a week or two is bad. After I lost one engine, I installed a replacement (with this forum's help btw, thanks!) and my local mechanic told me that as long as I use a fuel stabilizer, I can keep fuel in the motors in between uses. His thought was to reduce wear by not starting the motors without oil/fuel for this first few turns especially when those rings have been sitting in the cast iron block for a week, rusting away. His theory was that this was the reason I lost compression on the scrapped motor's number 2 cylinder.

I live in California and my boat lives in the water so the most I ever go without using the boat is maybe a month.

What are your thoughts, with or without fuel?

 

[mars bar]

Re: To store with or without fuel?

I've used fuel stabilizers before, but that's when I store it of a couple of months. If I use my boat every weekend, I don't believe you need to empty your lines. Just look it up by doing a search.

 

[tashasdaddy]

Re: To store with or without fuel?

leave the fuel if using regularly, if putting into storage, pull the carb drain plugs, and tilt the motor up, let them drain, then replace the plugs.

 

[Brew2]

Re: To store with or without fuel?

I'm with your mechanic. Leave the gas it the carb so that it will have lubrication upon startup.

I've never had a problem leaving untreated fuel for several weeks between boat uses. I use a fuel stabilizer when storing for 2+ months.

 

[asdasc]

Re: To store with or without fuel?

I generally use fuel stabilizer all the time, but I normally make just a few short trips and only on weekends, so I don't go thru more than a tankful every month or so. This way, if I can't get out on the boat, I don't have to worry about it. If you burn a full tank every week or two, obviously that is different.

 

[iwombat]

Re: To store with or without fuel?

You never want to run a multi-carb motor out of gas. On your three-cylinder, the top carb goes dry first, then the middle, then the bottom. It'll run on the bottom cylinder just fine while the top two are pumping dry w/o lube. If you want to drain the fuel, do what TD said and use the drain plugs. Otherwise, just use stabilizer and let it be.

 

[kenmyfam]

Re: To store with or without fuel?

Regular use like yours should be no issue to leave the fuel in. Add stabiliser if you are worried.

 

[John90290]

Re: To store with or without fuel?

Thanks for all the advice! As usual, this is a great source of information.



-John