Battery, Bad Connection, or Something Else?

[simek3ru]

Hi, looking for some suggestions to my recent problems listed below.

 

Setup - 2007 Tracker 175
Starting Battery size 24 (April 2015) - bow (old stock one) and console (Garmin Striker Plus 9SV) fishing finders and motor 
Deep Cycle size 27 (December 2012) - trolling motor

 

Problem History from my last 2 outings:

First Trip
1) At boat ramp ready to launch - my motor trim would not work. Electronics worked though.  Swapped all my connections from my starting battery to deep cycle, still didn't work. Moved them back to the starting and it worked

 

Second Trip
2) Motor stalled at idle at launch
3) After first run, motor would not crank at all but when I turned it to "on" position my gauges were active.  Removed battery connections then placed them back again, motor fired up
4) After second run, motor would not crank at all and when I turned it to "on" position my gauges were off and I had no power.  Removed battery connections then placed them back again, motor fired up again.  Made one more run and it fired up after that when I went to head home.

Took the starting battery out of the boat and went to AutoZone to get it tested, they said it was good.  Not sure I really trust whatever test they do.

I'm wondering if my starting battery is going bad or if I just all of a sudden have a bad connection.  Could this be something else I'm not thinking about?

 

Thanks!
Jason

[slonezp]

Check and clean battery terminals and ring connectors. You can use sand paper or a wire brush. Also check the connections at the ignition switch, kill switch, and starter and make sure they are not loose.

[simek3ru]

36 minutes ago, slonezp said:

Check and clean battery terminals and ring connectors. You can use sand paper or a wire brush. Also check the connections at the ignition switch, kill switch, and starter and make sure they are not loose.

 

Thanks.  Sorry, probably a silly question.  Where is the starter connection to check?

[slonezp]

The starter connections would be under the engine cowl. Exactly where on your motor, I don't know.  You would need to look at a service manual. 

[BigAngus752]

I always try to look for a common denominator when diagnosing a "no start" (bear in mind I'm a car/motorcycle guy, not a boat guy).  The common denominator here appears to be that when you have a problem you pull the cables off the battery which jerks the cables around. You already know your battery is good because you had it load tested.  So you are just jerking your battery cables around and then suddenly you have power again.  I would start by looking first to make sure you have a solid ground and then inspect the battery cables.  I would then work my way up, inspecting the wires up to the next switch in line which should be the ignition switch or kill switch. 

 

The fact that you are getting SOME power some of the time is telling.  On your first trip out your power trim didn't work (power trim draws a very significant load) but your Garmin did work (very small load).  So you had some kind of connection, just not a good one.  That would point me toward a ground or an interruption in a line (loose connection/failing switch/loose fuse/etc.)

 

Bear in mind that these are just guesses.  That what diagnostics is.  I would grab a multi-meter and a flashlight and start following wires.