Mariner 40 Keeps blowing main fuse

[mark10187]

Hi guys I've got a mariner magnum 40hp it keeps blowing the Main fuse only when run above 3000rpm thinking maybe the voltage reg could be stuffed

[hookmeup]

Hi guys I've got a mariner magnum 40hp it keeps blowing the Main fuse only when run above 3000rpm thinking maybe the voltage reg could be stuffed

Could be the reg, but eliminate the obvious first,a short, check all wiring & electrical connections, even in your control box, could be pushing a loose terminal to earth when you push it in so far.

[a boat]

Hi, I doubt it will be the voltage regulator and as mentioned check the basics and if it only blows the fuse when over 3K RPM then in the control box will be a wire that gets caught when at this RPM.

Cheers,

Huey.

[mark10187]

Thanks for the replies guys pulled the control box apart and found the buzzer alarm wire rubbing