Stalling at idle

[ethelwright]

I have just bought a 1987 mercury 80 hp oil injected outboard on a 16 foot Grew Fiberglass BR.Last weekend while out with my daughter the motor was running rough and had no power. I took it to the shop and they replaced the switchbox .Today when we were out I noticed the motor would hesitate when I punched the throttle although it did get up on plane. Then it did a strong shudder while we were out . This spooked me as we were headed out on lake superior so we headed back to the boat launch . On the way in to dock it stalled when in neutral , idled rough when it chose to and then was hard to start although it was well warmed up . When I did get it to start it smoked a lot then promtly quit again. I was very careful not to push the choke button. Any ideas out there?

 

[The Marine Doctor]

Re: Stalling at idle

Did you knowtice if there was water comming out the tell tail on the starboard side of the engine?<br /><br />TMD

 

[ethelwright]

Re: Stalling at idle

I took the boat back to the dealer I bought it from and they did 2 hours of sea trial testing at no charge.I was trimming the motor too far dowm and the exhaust relief holes were below the waterline. The dealer and mechanic gave me a lesson on when to trim way down .When I start the motor or plug along slow I have to trim the motor up so the holes are above the water . When I want to go fast, as I frequently do , I trim down , punch the throttle and trim up when the boat goes on plane .