Boat misses when hot on restart

[Gary Axe]

I have a 2010 Nautique 200 with 5.7 engine
680 hrs it runs perfect until you run it until it gets hot and you
shut it off for days 30 minutes. Then it will start back up but when you try to accelerate
it misses and backfires for a few minutes then runs perfect again ! HELP
GARY

[SilentSeven]

Call the guys at skidim.com and see if they have suggestions on how to diagnose.

[jpwhit]

How long has it been since you replaced the distributor cap and rotor? The 5.7 Vortec based motors are notorious for cap and rotor to cause issues unless they are replaced on schedule. And you can't tell by looking if they are bad. That distributor is also notorious for the plastic screw ears to break off the distributor base. Dorman sells a plate to take care of that issue. You can find it on Amazon.

[srock]

I have a Malibu direct drive that did the same thing. The engine enclosure temp rises significantly after shutdown and the increaded heat was vaporizing the fuel somewhere in the system. This could happen an hour or more after the shutdown. I found cracking the clamshell or running the blower a little about 15 minutes after shutdown would cure the problem. See if venting cures the problem before chasing other solutions.

[Gary Axe]

Another question does a 2010 Nautique 200
have the old type packing nut on the prop shaft
so by tightening it up or putting in new packing you can stop it from leaking?
I have water leaking into my boat from somewhere
man’s figured this is the most likely place! Any other thoughts! Gary

[billywro]

Went thru similar symptoms with my 2008 220 w/ EX 343 with 600+ hours. Turned out to be a leaking exhaust manifold gasket was fouling two plugs/cylinders while it sat, but cleared up after the engine heated up. I should have figured it out earlier because I noticed the engine was louder than usual, but didn't connect the dots until I pulled the plugs.

[jpwhit]

Another question does a 2010 Nautique 200
have the old type packing nut on the prop shaft
so by tightening it up or putting in new packing you can stop it from leaking?
I have water leaking into my boat from somewhere
man’s figured this is the most likely place! Any other thoughts! Gary

Two more common leak points on the 200 is having a screw missing from the hydrogate or having a hole in the fiberglass muffler. Don't buy a new muffler if that's the source of the leak. They are easy to fix by fiberglassing over the hole.