Battery Drain Check

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
Good Day,
I have an old 1992 Renken with a 2.5L OMC. I have something motor related draining my battery. I put all accessories behind a master switch to rule that out and the problem persists. Can someone walk me through tracking it down and any likely culprits. The boat and more are all original with 190 hours on it. Was a garage find I am the second owner.
I did some searching for "battery drain" so apologies if my searching was weak in this area.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,414
Are you sure you isolated everything but the motor behind the switch? Bilge pumps are typically direct wire.

For a test, pull the hot wire off the starter solenoid. See if that solves the problem
 

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
I charged the battery and disconnected the hot from the starter. It dawned on me this is the only hot that goes to the motor at all so with that disconnected I don't think anything can drain? See photo. The other wire from the hot battery terminal goes to my master switch for accessories. I also completely disconnected the bilge pump.
 

Attachments

  • photo334531.png
    photo334531.png
    1 MB · Views: 0

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,414
I charged the battery and disconnected the hot from the starter. It dawned on me this is the only hot that goes to the motor at all so with that disconnected I don't think anything can drain?
Its a process of elimination.... if the battery still drains you've removed the motor and any circuits powered by the motor from the equation.

Where did you disconnect the bilge pump from?

If you have the typical 3 way switch (on-off-auto) its possible you can get power being back feed from multiple locations. I've seen some crazy stuff happen when a bilge pump and or float switches
 

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
I traced the wire to the bilge to a blue wire connector I don't know what its called but where you splice without solder and crimp it I dislike those so I cut it and pulled out and taped them off for the time being. I connect my meter inline with the motor and looked for a parasite draw but got nothing. I did them same for my accessories. I showed 12.67 on the battery but the starter seems so sluggish. Maybe I am chasing a bad starter?
 

Grub54891

Vice Admiral
Joined
Jun 17, 2012
Messages
5,908
Maybe I am chasing a bad starter?
Clean all the connections, including the grounds at the back of the motor. Then if the battery itself isn't going dead, yes you have a bad starter. Start it up and feel the starter, is it hot?
 

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
Connections cleaned, nothing connected but the motor and the front dash / key. Battery was at 12.68, I hit the key, it spun fast for the first 2 seconds then it slowed down to about 1/2 that. Turned off the key and checked the battery and it was at 12.67. I am going to get the battery tested next its 800CCA for reference.
 

dingbat

Supreme Mariner
Joined
Nov 20, 2001
Messages
15,414
Connections cleaned, nothing connected but the motor and the front dash / key. Battery was at 12.68, I hit the key, it spun fast for the first 2 seconds then it slowed down to about 1/2 that. Turned off the key and checked the battery and it was at 12.67. I am going to get the battery tested next its 800CCA for reference.
Assuming the voltages you listed are accurate, the change in voltage when you engaged the starter, and the resulting rebound in voltage when stopped is normal. Nothing wrong with a 12.68 volt battery.

Sounding more and more like you have a Starter on the way out
 

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
For ref the starter did not get hot and thanks for your help.
Will keep updating this thread but might be a few weeks before I get a starter.
 

Poor_Boater

Cadet
Joined
Jul 6, 2020
Messages
7
So I think my bilge pump was bad I let it sit for day and just went out turned on the water muffs and it fired right up battery and started sounded strong.
Thanks all.
To be fair I also did new distributor cap, points, can condenser and that helped it start so much quicker.
Thanks to all.
 
Top