Just wondering if anyone has ever had a carb motor go lean due to water in fuel. Shortly after getting out of the idle circuit my afr go to 18-22. Kinda hard to believe considering its got 95 jets all 4 corners and is no where near WOT. Took my carb to a rebuilder of 35 years and he said sounds like water. Took a fuel sample and found some water in it...

Water will lean it down, but would have to be a specific amount as much will cause to run bad and not at all...

Wouldn`t that be like meth injection,(you can use plain water) I wouldn`t think it would make it go that lean.. you have water seperators? Pretty sure your motors would be toast @ 22 AFR

Im not sure about the water deal, but if raw fuel hits the o2 sensor it can make it read WAY lean.

Just wanted to throw that out there

Read lean or run lean ?

2 very, very different things.

i seriously doubt it is running that lean.are you getting some reversion causing the o2 sensor to read incorrectly?how does it seem to run?

She is definately lean. I think I'm starting to get a complex from all the lean popping. As soon as the afr climbs it pops. My exhaust is dry and the water dumps out the side of the boat so really no chance of that. My carb is brand new and when I took it apart the first time I thought to myself what a POS there was some white powder in one of the upper corners of the metering block which is billet and anodized. I didn't think anything else of it until I was talking to the carb guy and he said gas will not corrode aluminum only water. I thought to myself "duh" why didnt I pick up on that. I had the carb guy take it apart and make sure it was 100% he returned it to me with the old metering block gaskets and bowl gaskets. This time all the gaskets had white powder on them.

did you by chance loan the boat to ratman?i had a similar problem but i thought i had a load of bad ethanal fuel,i cleaned the carb and dumped fuel filter and dumped the fuel.problem went away,maybe i to had water in the fuel.i did not have any lean popping but it just had no power.

You have carb issues, and yes, I have had multiple carburetors (mostly non anodized billet Holley based) get gummed up from electrolysis. White powder, some had white granular jelly. All since our area went fully to E-10..

If it's been throughly cleaned, maybe it's possible your new carb is is improperly made and/or calibrated.

You are in the area of hurting your motor, so after making adjustments, replacements, etc, right when you see over 13 or higher, back right the F off, and go back to more tuning and/or repair.

Have you talked to whom ever built the carb ?

The engine wouldn't run at 18-22:1, at least not for very long lol.

If your engine is "popping", it is misfiring. A misfire will show a lean condition on an 02 sensor. An oxygen sensor reads oxygen, not fuel. During a misfire you have unburnt oxygen which spikes the reading.