ethanol fuel and fuel pumps

[mroussey]

There have been several threads about ethanol fuel and fuel tanks, etc. However, what is the impact on the fuel pump? my neighbor has a 1997 33 sundancer and just replaced the fuel pump and he said the ethanol fuel broke down the diaphragm within the pump. Any throughts?

2001 27 sundancer

 

[BonBini]

Where was he buying his fuel at? .... Marina or Speedway self serve?

 

[Lazy Daze]

His boat is well beyond the "possible" problem years (?mid 80's, maybe?). Unless he's pumping in E85, the normal E10 is just fine. Is it the original pump? The fuel pump dying is much more likely due to age or foreign material in the gas.

Note, I'm not a chemist - just relaying info that's been provided to service departments over the last few years by Mercury.

 

[mroussey]

buying gas at the local marina in St Charles, MO area on the mississippi river location. He wasn't sure but someone told him that and I was just checking because we buy fuel from the same marina.

It was the original fuel pumps - I have always heard they work or don't - no in-between.

 

[SCORPIO]

Ethanol, even E10 is hard on rubber parts like hoses, fuel pumps, and carb accelerator pumps etc... Its not good for aluminum fuel tanks either, reacts with water and get corrosive.

 

[Alegria]

I have the same fuel pumps both of mine are new. The starboard one was replaced prior to purchase, the port replaced as condition of sale as it failed on sea trial and was original. So yes they do wear out.

There is an oil reserve on them that lubricates the cam that pushes the pump. The cam is operated via the water pump. Dumb design but it works, for a while. Usually it's best after several seasons to replace the lubricant in the fuel pump. Also there are site tubes, lean over the engine and you will see clear tubes, if there is fuel remaining in them after the engines are off for a while then its a sign of the fuel pump's diaphragm staring to go. (At least that is what I've read here for what it's worth..)

Overall not an unusual occurrence and he did get a long life out of them if they are original! I believe I read here in another thread that the pumps can be rebuild with new diaphragms... may save him some money..