Engine bogging than dying when hot.

[kaczman]

Hi guys. Quick problem/ question. Have an 01 maxum with a 5.0 merc carbed. On the Water for 30 minutes, everything was fine. Then it felt like the motor just shut off, bogged out and died. Started right back up, runs good for a few minutes then the idle drops and it stalls. You can see the idle drop to like 300 then back up to 800 once or twice then it just dies. Starts right back up and same thing over and over. Any ideas?

[jrsick]

I've heard of this happening a couple of times, and both times the problem was moisture inside of the distributor cap. Either the cap was cracked, or it didn't seal properly at the base.

[mmwjr]

A weak ignition coil may also cause this in addition to what jrsick mentioned.

[MoonRiver]

I had those same issues on a previous boat (94 Crownline w/5.7L) I ended up replacing a bunch of stuff to figure it out. New coil, plugs, wires, distributor cap & rotor, and fuel filter. I can't remember which one of those was the golden ticket.

[jparsons121]

Fuel filter/separator.

[Gugi47]

Originally Posted by kaczman

Hi guys. Quick problem/ question. Have an 01 maxum with a 5.0 merc carbed. On the Water for 30 minutes, everything was fine. Then it felt like the motor just shut off, bogged out and died. Started right back up, runs good for a few minutes then the idle drops and it stalls. You can see the idle drop to like 300 then back up to 800 once or twice then it just dies. Starts right back up and same thing over and over. Any ideas?

I have exact this problem. I end up to replace the exhaust manifolds.
Next time you go out, see if happens again. If run for 1/2 hour good and after that missing I would look in to the manifolds. After get hot everything expend and that's when water can get in the engine. Maybe only the gaskets are bad....
Let us know what you find. Everybody have a good suggestion here.
Good luck

[jrsick]

Gugi, how did you diagnose that you had leaking manifolds? Did you see oil level rise?

[Gugi47]

Originally Posted by jrsick

Gugi, how did you diagnose that you had leaking manifolds? Did you see oil level rise?

Don't was that bad. Newer got water in the oil. was very small like but was making steam and that shot of the engine and give sound like backfire. My mechanic say, that is the problem. But if is not will take the new exhaust manifolds back.. He was right. When I take it off, I can see some, like gold drops inside of the manifold. Probably if I would replace only the gaskets would stop the problem, but I just replace it with the new set and I keep the old set just in case. This is a 5 L engine with 3 inch risers.
So this is my story.