NO START WHEN CONNECTED TO OLD/NEW FUEL PUMP

[capnward]

Thanks to Sam for informing us how his fuel issue was resolved. Bad fuel is in my opinion the main cause of our problems. Every spring I disassemble and clean the carb and replace filters, to be pro-active. My tank was "cleaned" about 15 years ago when a gas dock in another town mistakenly filled it with diesel and pumped it all out. Apparently, my marina's fuel dock (non-ethanol) has high enough volume. I put about 200 hours on the engine last year. The good old A4 ran like a champ despite having well over 3000 hours on it since the rebuild in 2001. I still need to get an O-ring for the fuel fill, which is covered in the off-season. I operate in a quiet area where most of the water that gets on the fuel fill is from a hose. That photo Neil provided of carb contents shows a good example of what happens when fuel/water filters are overwhelmed.

[joe_db]

That photo Neil provided of carb contents shows a good example of what happens when fuel/water filters are overwhelmed.

Keep in mind this is a very different thing than in the old days. It used to be that water was heavier and would separate out in a filter and could be drained off one way or another. "Overwhelmed" was too much water.
Now well before we get pure water, we have a goopy mix of gas, ethanol, and water. I know of no filter that can deal with that. My own experiments show that some filters just clog up and pass nothing at all and others will pass all of it. When I called RACOR about this they confirmed their filters were not designed to deal with ethanol/water/gas mixes.

[W2ET]

Years ago, I was befuddled by a Honda outboard which refused to run, even though the contents of my beautiful Racor filter/separator were absolutely clear. Eventually, I figured out that the contents were 100% water which had not yet emulsified.

Bad o-ring on the deck fill.

Bill

[ndutton]

There are no dumb questions

I just received a good question from one of my slip neighbor projects with water in the fuel:

Could you explain what clean the [fuel] system means?

My reply:

Simply removing and replacing the fuel may not be enough. Like we discussed, replacement of the fuel filters is also necessary and after that is all done, I recommend pumping fresh fuel through the system with the final connection to the carburetor left undone. This can be accomplished with something as simple as an outboard style squeeze bulb. Catch the fuel that comes out and inspect it in a clear container to confirm there is no more water or other contamination coming through. If contamination is still there, more flushing should be done and the filters replaced again. Only then should the final hose connection to the carburetor be made and the engine started. And of course, replace the fuel fill deck plate O ring.

edit:
I'm not immune to water contamination either, it happened to me too. Once.

https://www.moyermarineforum.com/forums/showthread.php?t=11084