2007 mercury 50 hp blow fuse when trim

Jons4rd

Cadet
Joined
Mar 16, 2010
Messages
6
I just bought a 2007 boat with a 50 hp mercury 2 stroke and it is like new. the 20 amp fuse on the motor keeps blowing when I trim the motor while in the garage. It will move up and down fine and then all at once it stops moving. I twill do the same thing from any of the three switch location that i try it from. The motor switch, the throttle/gearshift switch, or the bow switch. I have done a basic look over the wiring and find no obvious shorting connectors or wires. the trim lock pin on the motor is pulled out so that it is not inter ferring with the motor operation. Any help would be appreciated... I drove 6 hours both ways to pick it up. Therefore i cannot just take it back to the dealer and says fix it. I just purchased it Friday March 12th.
Thanks,
Jon
 

milehighboater

Petty Officer 1st Class
Joined
Jul 28, 2009
Messages
235
Re: 2007 mercury 50 hp blow fuse when trim

I would take a look to see if there is a fuse map and ensure it is a 20 amp that belongs there. Maybe in a pinch someone threw that one in there. Also does it blow fuses when the trim motor is not running?
 

Jons4rd

Cadet
Joined
Mar 16, 2010
Messages
6
Re: 2007 mercury 50 hp blow fuse when trim

The fuse does not blow when the trim is not being used. It states in the motor maintenance manual that it should be a 20 amp fuse.
 

Jons4rd

Cadet
Joined
Mar 16, 2010
Messages
6
Re: 2007 mercury 50 hp blow fuse when trim

The fuse only blows when I trim down. I can hold the trim down button only a second at a time and continue until the motor is trimmed all the way down and it does not blow. It does not blow when I trim up.
 

saumon

Lieutenant
Joined
Aug 2, 2004
Messages
1,452
Re: 2007 mercury 50 hp blow fuse when trim

Look like you have a short to ground in the down circuit.

This might help, particulary the pages 25 and 26.

http://freepdfhosting.com/4a3b057deb.pdf

Look, at the page 5C-25, at all the wires coming from or to the down relay and inspect them, there should be something, like a frayed wire, between this relay and the place where the green/white and blue/white wire meet, cause all your switches are working so the problem is past them.
 

Jons4rd

Cadet
Joined
Mar 16, 2010
Messages
6
Re: 2007 mercury 50 hp blow fuse when trim

Thanks for the help. I used an amp probe and it pulls sometimes as much as 24-25 amps when trimmimg down.
 
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