Starboard Engine will not shut off

[MIKENVAHBEACH]

To all<br />I am posting for a buddy, he called me and said his 1999 29' Shamrock walkaround would not shut off. The boat has twin 5.7l mercruiser inboards, we tested the ignition switch and it is good, even switched the port to starboard and same thing, engine will not shut off. This is about as far as I took it. Where to go from here? Check ignition? Alternator cross wired? It is also tripping a breaker that is part of the ignition when the motor hits 3100 rpm's, I think this may be related, since this too is on the starboard motor.<br />Thanks<br />Mike

 

[rodbolt]

Re: Starboard Engine will not shut off

can you describe the fuel and ign systems better or post a seriel number. could be a lot of different versions of the 5.7. and what was the last maint or work done on the boat before this problem occured

 

[MIKENVAHBEACH]

Re: Starboard Engine will not shut off

The engine is getting fuel and running fine, just will not shut off, I will get more info and post

 

[rodbolt]

Re: Starboard Engine will not shut off

not what i asked but ok

 

[KaGee]

Re: Starboard Engine will not shut off

Wonder if he's run out of fuel yet? <br /><br />Sorry, couldn't help myself!

 

[Don S]

Re: Starboard Engine will not shut off

All it would take is installing a new electrical device at the help and power was picked up from the wrong place could cause it, along with electrical items on the engine being fixed or replaced. What rodbolt was wanting to do was narrow it down by looking at things done just before it started doing this instead of looking at every wire on the boat.

 

[MIKENVAHBEACH]

Re: Starboard Engine will not shut off

Yes, I'm sorry, as I stated its not my boat, I will try to get my buddy online as he would be of more knowledge. Thanks anyway.

 

[rodbolt]

Re: Starboard Engine will not shut off

arright <br /> the other thing was the amount of IGN systems and such used by merc over the years. maybe 4-6 at anygiven time depending on the seriel # production run. try to get an engine seriel number if nothing else. and ask him if anything was done prior to this failure.