Turning key cuts power - 2001 merc 3.0

[superfitz]

I have a 2001 Bayliner Capri with a merc 3.0. I've used this site to solve a lot of small issues and thank you all for the advice. My current problem I can't seem to fix. While spring prepping I changed the starter, started the boat up first crank. I was very happy.
Let the boat sit about a week, ran the blower, then when I turned the key, it cut all power to the boat. Nothing worked, not even the horn. I came back to it a couple days later (today) and the electricity was back. I had not touched anything. So once again, ran the blower, turned the key and heard the starter click, then lost all electricity. I've used a multimeter and there is definitely power getting to the starter, and solenoids as best I can check. While I was testing cables I went back and tried the blower again about 20 mins later and it turned on. Cranked the starter and off it went again. Any idea on why I'm having this problem or what else to check?
Thanks.

 

[Fordiesel69]

Re: Turning key cuts power - 2001 merc 3.0

I bet its a battery connection. I had this problem with my truck everytime I cycled the glowplugs it would cut all power. Funny thing is I still had voltage showing on my meter at the GP relay. However when it drew high current, the dirty connection dropped out. My cable was shot. Check your cable ends also.

 

[Bondo]

Re: Turning key cuts power - 2001 merc 3.0

Ayuh,... You've got Corroded connections somewhere....

It's carrying voltage for testing, but breaks when amperage is called for....

 

[Juniinc]

Re: Turning key cuts power - 2001 merc 3.0

+ time for a new battery possibly.

 

[JaseBosto]

Re: Turning key cuts power - 2001 merc 3.0

Battery connections.............

 

[superfitz]

Re: Turning key cuts power - 2001 merc 3.0

I think you guys are right. I tightened up the connections, put some grease and the nuts and it worked. I'm going to get a new cable tomorrow and put her through the paces but I think that's it. Thanks for all your help.

 

[bruceb58]

Re: Turning key cuts power - 2001 merc 3.0

Had exact problem last year. I took all my connections off and cleaned them down to bare metal and connected them back up. Unfortuantely for me I was 12 miles offshore when mine acted up...not fun.

 

[Fordiesel69]

Re: Turning key cuts power - 2001 merc 3.0

Another thing that may be worth it, is to source a nice USA made starter bendix solenoid. It is the small round thing on your starter. It is responsible for slamming the bendix gear out and then applying power to the starter motor. This will often fail as well in a marine envirnoment, and when it does, you can get a no start.

I would also plan on applying a nice lubricant over the battery connections and starter connections AFTER they are tight. This will keep the moisture out.