I have been having fuel issues all year and just took my outboard motor apart this weekend as part of preparing to winterize - The inside of almost every hose was eaten by the fuel and the fuel pump diaphram was "fuzzy" with erosion.  I only use high quality parts (usually Merc OEM) so this was quite a surprise that the fuel would do this in just one season.  I have had some issues storing gas over the last few years with the higher ethanol blends not running well after storage, and as a result switched to storing higher octane gas with additives to keep the fuel from separating, but this season was all fresh fuel.  My lawnmower also needed new hoses this season, although it's 5 years old so it was kind of expected, but I took a good look this week and found the plastic fuel tank had black gunk in it kind of like the erosion of the hoses.

I asked my local marine mechanics if they were seeing this and they confirmed they are seeing it everywhere.  One suggested Merc brand fuel stabilizer (which he said was cheaper online) or Starbrite as he said they work a heck of a lot better than Stabil, etc, but that nothing was helping the hoses and parts, and like me he was seeing the problem in boats run on any kind of fuel, stored or fresh.  

Like many of you, I store gasoline as a prep item and keep what I thought were sufficient parts for normal breakdown, but I am having going to get more spare fuel hose for longer term problems given this fuel issue.    I am taking apart the generator this weekend to ensure I don't have a similar problem there.  Even if I don't, I am going to ensure I get the best grade hoses available and have lots of fuel system spare parts on hand.

Anyone have any recommendations on stabilizer that ensures the fuel stays more fresh and doesn't eat hoses/seals/diaphrams?  
 

GO GREEN!  SAVE THE PLANET!!!

Pri-G is what you should be using.  

I just had to go through a carb and replace a fuel pump on my Yamaha Rhino.  It was fooked in 6 months.  I had been busy on a project and had not started the thing.  The fuel was untreated, because..............well.........it was only 6 fricking months.  Even after replacement and cleaning twice it took a while to start running right, even with a new plug and fuel filter.

I know better.........Pri-G has not failed me when I use it.

Stabil is useless.

The black crap is a chemical reaction between MBTE and E10.  You can not mix the two.  Gas stations must clean the tanks for conversion to ethanol.  

This is my line of work, what I have seen.  Is a boater will have one tank full of last seasons MBTE. They fill up another tank with fresh E10.  Either they equalize to improve trim or a return line goes to the other tank.  The two gasolines mix and blow the valves, carbs or injection systems.

Sorry for your problems.  All the manufacturers knew this was coming.  They saw Ethanol wipe out all the outboards in Brazil when they changed over ten years ago..  Only Yamaha made design changes and engineered alcohol resistant hoses.

Yes!  PRI-G is wonderful stuff.  Offshore in the Gulf it will sit in vented tanks at 100 degrees and still run fine after six months.  Don't use too much –– there is no point.

ETA:

And because everyone is having the same issues, the OEMs are gradually pushing the ethanol/methanol/MBTE/etc.-resistant parts through the supply chain because the lawsuits are starting to fly.  This will take a few years, though.  When you replace the rubber parts next year, try to get the newest models possible, probably with a different part number.  By then the new stuff should be out and widely used, but the warehouses will be getting rid of the old stuff for a while, so be careful.

ETA:

Gasoline with ethanol is problematic in 45 days in most plastic tanks.  The lined CARB tanks do pretty well, but metal is best, and that will push you out to 4 months, but the new fuel won't last without PRI-G.

Yamaha 4 hp, 4 stroke,three months and my carb and fuel pump diaphram were toast, with stabilizer added. The mechanic where I got the parts is very busy. He also said that they have just purchased an ultrasonic carb cleaner, as the new fuel residue is not removeable with carb cleaner in the traditional method.

Which stabilizer?