Mercruiser 140 Alpha One Stall when turning

"Ok this is bizarre. The one M

"Ok this is bizarre. The one Marine mechanic I told this to thought I lost my mind. I finally got my boat out for the summer, and after many hours trying to get it to idle right adjusting carb and timing, only to discover a dead cylander due to a bad plug wire, I finally got it on the lake. The boat was running great, all kinds of power, and great acceleration out of the hole, the timing must have been spot on for once.

I got down to the end of the lake near the dam and started to turn, and the engine just stops. The momentum of the engine keeps it spinning, but the ignition just stops. It is weird hearing an engine decelerate from 4500 without any combustion. Then of course it is a hard start again, probably because it gets flooded out with the Carb being still WOT and no spark. The weird part is that it is only in turns, and not super hard turns, just a gentle turn will do it. If I am really super gradual in a turn I can keep it from happening. Probably something to do with the throttle linkage and the cut out switch perhaps? Not sure why it would only do it when cornering though. Doesn't matter which direction I turn. The other weird thing is that even if I straighten it out while the engine is stilling spinning ignition does not return. I am considering possibly water in the fuel and the turning causing a water layer in the tanks to be picked up instead of fuel?

It does not seem as if the sterndrive is binding, though it could probably use an overhaul.

Thank you for any ideas"

What year is the engine? What

What year is the engine? What type of fuel pump; electric or mechanical? How much fuel in the tank?

"Sorry thought my profile post

"Sorry thought my profile posted the specs.

It is a 1986, mechanical fuel pump, full tank of gas.

Thanks."

"If you think it's in the

"If you think it's in the fuel tank, than remove the fuel line from the inlet of the fuel pump and hook up a outboard fuel tank. If it still happens it's not your onboard fuel. This sounds like a possible electrical problem. with the engine running at the dock wiggle the harness and all the wiring. Let us know what it is when you find it."

"Didn't know condensation

"Didn't know condensation on a full tank over winter could get that much water in the tank, but I tell you when I pulled the filter off the fuel pump housing for the fourth time I could see plain ole water, about a teaspoon, sitting on top of the pump gasket.

Seafoam. Like $9 a bottle, and the Marina mechanic at Bald Eagle State Park, and his son swore by it. I was majorly skeptic, thinking, it's just a super expensive bottle of dry gas.

I finally decided $18 was the easiest/cheapest thing I could do next, and it worked like a charm. I put two bottles in. 1.5 in the fuel tank, and 1/2 in the crankase (it takes moisture out of oil too.).

The first corner I took hard, it almost stalled out on me. The second corner, the RPM dropped about 1500, (this was after I took it up and down the lake 2x, hitting lots of waves and wakes to shake things in the tank up a bit). The next hard corner I took the RPM dropped a couple hundred, then I started doing serpantine turns to really get the fuel sloshing around in the tanks. After that it would do anything I wanted it to.

I am now on the market for an inline fuel water seperator with a visible fuel/water bowl and an openable petcock to drain off any visible water/sediment w/o having to take off the filter.

(Um actually the water in the fuel probably came from the fact I had my battery disconnected while on the lake side slip during a nasty rainstorm, so no bilge pump....by the time I got there the water was well above the top of the fuel tank, and I have since noticed that I need to replace some fuel filler and vent lines that don't look exactly water tight...)

Now I've got an automatic bilge pump wire straight to the battery. Was considering a solar panel to make up for stray voltage loss, and they few thousand milli-amp hours I expect to lose from the battery from periodic storms and such.

Sooner or later I am going to have experience the majority of what can go wrong with a boat, and then maybe I can avoid them!

I could actually see water vapor condensing on my throttle plates and throttle body too.

Thanks for the help and good luck all."