Fuel pump pressure

[Jimmyy]

When ethanol sits it turns bad. I replaced a fuel pump in my B3000 and there was some goo in the bottom of the tank. Kind of a waxy looking gunk. In small engines it clogs the jets in the carburetor. This takes 4-6 months. With a fresh supply running through its a excellent cleaner. When I had 40psi the truck would start and run for about a second and die. Yesterday it started hard but kept running like normal. So I decided to check the fuel pressure. I had 45psi with the key on, and 55psi at Idle. The needle was bouncing so yeah it could have been 50psi. My $13 Chinese fuel gauge could be off some. The extra 5psi made the difference. Not sure on the fuel pressure regulator all I could find online was the 2004 does have one. Rockauto doesn't list it as a part for 2006.

 

[Fless]

Any gas will gum up and clog a carburetor jet if it sits that long; that's bordering on abuse IMO. I always run only ethanol-free in my small engines and add STA-BIL to any fresh gas I buy. And run the gas out at the end of the season. I can't tell you how many mowers I've picked up in springtime because people didn't run the gas out in the fall. Get 'em for free, clean the carb and service 'em, and sell 'em or give 'em away.

So the E85 in mine must get cycled through fast enough to not experience the gum-up.

 

[Jimmyy]

Back in 2000 I was doing some work out in Buffalo NY, at that time I was working with a gas station chain. They had just started using ethanol in there fuel. They started having lots of problems with the ethanol going in to the storage tanks at the station stores. It had loosen up a bunch of crud in the tanks and ended up in customers cars and killed their fuel system. The "fix" was to pump the fuel out of the storage tanks and add it back in to the bulk tanks (millions of gallons in the bulk tanks), and to replace the type of filters on the stations pump. This wasn't the waxy gunk from sitting but the cleaning action from the ethanol. Ethanol is a thing in my opinion because Iowa is/was the 1st primary state. A ethanol plant can not run itself on ethanol. They are trading Natural gas to turn it into alcohol.

 

[rockola1971]

Ethanol is corrosive and it will attack aluminum carbs. Ethanol also attracts water which will cause all water droplets in your tank to collect in one area with the ethanol and then when it gets sucked up by the fuel pump it will cause your engine to not just run rough but not at all because the engine wont run on pure water once that pocket of water is in your fuel rail. Any gas will start breaking down around the 6 month mark and cause havoc on just about any fuel system from carbs to fuel injection. As @Fless said, never leave fuel in any tank over winter if the engine isnt going to be used in that season enough to cycle out older fuel. So if you have to store a vehicle over a long period be sure to add enough stabil into it to keep the fuel from breaking down.