OMC Cobra EFI 5.0L stopped and won’t start again

[Kielbuchholz]

Every year after sitting through the winter we have an issue with water in the tank even after we use ethanol free and gas treatments. The engine sputters at high speeds until we put new gas in the tank, then it’s fine the rest of the season. Yesterday we were out on the lake, and the engine just cut off while trying to run the water / gas out of the tank. We had it running for a couple hours with no issue besides sputtering at higher RPM’s. We slowly were able to get the RPM’s up as we ran the fuel out more. Then suddenly it just cut out.

After it cut out, we could not get it started again and had to be towed. The fuel filter did have a decent amount of water in it. Which I figured. But my guess is since it’s just cranking over but not starting, is the fuel pump? Or something to do with the fuel somewhere.

The boat is a Four winns with a OMC Cobra EFI 5.0L engine. Any ideas as to what you think it might be. Thanks for your time.

 

[alldodge]

Your not going to get enough water just sitting thru the winter to make an issue. You have something that is leaking water into the tank. If the boat is on a trailer

How and where is it stored? Pic maybe
What boat is it?
Where is the gas fill and tank vent?

 

[Kielbuchholz]

Your not going to get enough water just sitting thru the winter to make an issue. You have something that is leaking water into the tank. If the boat is on a trailer

How and where is it stored? Pic maybe
What boat is it?
Where is the gas fill and tank vent?

The boat is stored in my garage. It’s a twenty foot 1995 200 Horizon Four winns. It’s only an issue when we open it in the spring until we run the gas out of the tank? Unfortunately we left the tank full last year through the winter.

 

[alldodge]

Might be where your buying gas. Wouldn't be the first time it was coming from the station. Some have blown up brand new motors (1000HP blower type) by filling up at the wrong station

Many, many discussions on the tank level for winter, gas going bad, water, yet none have proof this happens.

Can you remove filter, pour contents out and refill with fresh gas and it fires back up?

 

[Kielbuchholz]

Might be where your buying gas. Wouldn't be the first time it was coming from the station. Some have blown up brand new motors (1000HP blower type) by filling up at the wrong station

Many, many discussions on the tank level for winter, gas going bad, water, yet none have proof this happens.

Can you remove filter, pour contents out and refill with fresh gas and it fires back up?

Removing and replacing the gas in the filter was the very first thing I did yesterday. Brand new filter. No luck.

 

[alldodge]

ok, then I'll forget about it being a fuel problem

Do you have 12V at the coil?
Have spark?

 

[Kielbuchholz]

ok, then I'll forget about it being a fuel problem

Do you have 12V at the coil?
Have spark?

I have not checked that. I do have a multimeter. How do you go about checking if there’s 12V at the coil?

 

[Kielbuchholz]

ok, then I'll forget about it being a fuel problem

Do you have 12V at the coil?
Have spark?

Based on what I’m looking at online. I’ve discovered there’s two circuit breakers one for the engine and one for the trim. It says if one of them is tripped it will click when you push it in and my 50AMP circuit breaker is clicking.

 

[alldodge]

Based on what I’m looking at online. I’ve discovered there’s two circuit breakers one for the engine and one for the trim. It says if one of them is tripped it will click when you push it in and my 50AMP circuit breaker is clicking.

Don't have a 5.0 only 5.8 manual. Not seeing what you have yet, but still looking.

The coil has 2 small connections. Put meter + probe on the + side of the coil and the - side probe to ground. With key turned ON see if you get power. If you do, leave probes on and crank motor to see if power stays there during cranking

 

[Horigan]

When I want to do a quick check for spark, I just pull a spark plug wire, insert a phillips screwdriver into the wire end, hold it near the engine block (1/8"), crank the engine and see if there is a spark between the screw driver shaft and the engine block. Make sure you are only holding the screwdriver plastic handle and that you're clear of the engine belts.

 

[Lou C]

My boat is always stored with whatever gas (e-10 is all we can get) was left in it but stabilized, stored outside in damp Long Island NY winters and I never see water in the fuel from the fuel filter when I dump it out in the spring when installing a new one. It is strange that you have this problem even with the boat garaged. My boat is always outside, either on a mooring all summer or in the driveway.....