Cannot kill boat

[Darrellwd]

2012 Tahoe q7 with a mercrusier motor. Boat would not turn over or start to crank. Tracked to the ignition switch was bad. Replaced with a new one. The boat will start now but you can't kill the motor with the key turned off or the kill switch at the throttle. Continues to run. Any ideas? Thnaks

 

[Bondo]

Ayuh,..... Welcome Aboard,...... Which Merc motor,..??..??
A serial number would also be nice,.....

 

[Fun Times]

Sounds sort of like a wire or two may be crossed or connected together… Maybe Post a photo of the back of new and old key switch’s. < Wires connected on new switch…. That or a defective or wrong type of new key switch used if nothing else was changed anywhere else.

 

[alldodge]

Agree need SN
If its a TKS carb might be the diode

 

[Bt Doctur]

or a diode in the alt allowing it ti backfeed. try removing the alt output led