02 50hp 2stroke 3cyl shuts down when warm

Hi, my engine ran great all last year this spring it had some problems stalling out at idle so I cleaned out the carbs and installed a new fuel pump diaphram kit. The engine ran great for about half an hour then it just crapped out while cruising and would not restart. I drained gas and put new gas in same problem happened after running it for another hour without a problem. The first time it crapped out I noticed the water pump indicator stream started to spray instead of coming out in a stream, few seconds later it shut down. Next time I started the engine in my driveway the water pump indicator (pee hole) was clogged completely so I pried out a piece of what looked like a thin piece of rusted material then the indicator resumed spraying water instead of it coming out in a normal stream. I have the feeling something possibly the coils in the engine are overheating but it is very frustrating since I had no problems last year. Could the slight blockage of the indicator hole have anything to do with the engine shut downs? Any help would be greatly appreciated.

Re: 02 50hp 2stroke 3cyl shuts down when warm

Yank spark plugs out and inspect them. If nothing unusual, next..................Do a compression check, with all plugs out, only takes a few minutes, post results. If you dont have a guage, borrow from autoparts store.
With a clogged water outlet, its possible to overheat. Could be a few things. So go with the easy stuff first. Also post manufacturer.
Im assuming you have a good pre-mix.

Re: 02 50hp 2stroke 3cyl shuts down when warm

The spark plugs look fine. I cannot run a compression check at the moment since the boat is at my mechanics getting a new starter installed. When it shut down last time both my buddies who also have boats wanted to take a shot at getting it started and I guess we turned it over to much in a short period. The engine is a 02 Merc 50hp 2stroke 3cyl. The engine ran fine for a few hours then right outside my harbor it gradually slowed down from full throttle then shut down in about 7-8 seconds. I had an issue when we first got out of the harbor where the engine was bogging down but I squeezed the primer and she took off. Regarding the premix I had pumped the previous gas out just squeezing the primer and on the first pump a little bit of water separation showed, after that we didnt see any problem with the rest of the gas. I still filled it back up with frest 87 prior to taking it out last. I am currently ordering a fuel water separator to help with any future water separation. I still think the problem could be something electrical overheating, but that is just a guess and I have no idea what it could be.