Parasitic current through outboard motor

[Fred]

I have been having problems with my battery running down over time. I have discovered that my stereo has some parasitic current so I have implemented a means of disconnecting it when I am away from the boat. I do not have a master battery switch.

My question is about my outboard motor. I have a 2001 9.9hp evinrude, electric start. I notice that with nothing else connected to my battery I am drawing 72 mA from the motor. I have traced it to the single red wire that goes to the regulator assembly. If I disconnect this wire the current drops to zero. I measured the resistance on the red wire with it disconnected. It is 45 Kohm through the regulator to ground and infinite when I measure the other end of the disconnected wire to ground.

This seems like a high parasitic current. Does anyone know if this is normal or what this red wire is for?

Note that the regulator was replaced last year because of battery charging problems.

 

[Chief RA]

Sounds like you need a battery cutoff switch. Stereos usually draw a few milliamps when off and do not know why motor is but it is still less than 1/10th of an amp. Harbor freight sells inline power switches for a few dollars. Chief

 

[Fred]

72 mA isn't much but it adds up to 12 A-hrs per week. My alternator is only 6A and I don't run it much or at high throttle. With other loads I am not catching up on my battery charge.

 

[centerline]

most modern alternators will show a slight draw from the battery when they are disconnected from the battery, and then reconnected.... this is the electronic circuitry within them "resetting/recharging".... when you disconnect and then reconnect, if you were to watch the test meter, you should see the draw slowly diminish to zero... this will take about 15-20 minutes and is normal.
most people dont take the time to notice this slow decrease and assume its a problem.

if it does not diminish to zero, then it could be an indication of damaged circuitry within the alternator.

but you must make absolutely sure there is no other draw on the system before assuming the alternator is a problem.

 

[Chief RA]

Do like Centerline suggests, or just get a switch! Chief

 

[walt]

72 ma leakage is WAY higher than it should be. A blown rectifier might leak like that. But if the rectifier is blown, the outboard also wont charge or the charging is way reduced.

Does the outboard charging system still work?

 

[Fred]

The battery voltage rises when the engine is running so I assume the charging system is working. This was not the case before I replaced the regulator module last year.

Unfortunately I do not have an ammeter in the circuit to monitor the charging current.

 

[walt]

Dont know.. but a power rectifier with specs to handle something like a 6 amp outboard charging system might have a leakage current spec of 1 ua or less at room temp and 12 volts. Might be off some for what is used in that outboard but.. 75 ma is 75 thousand times higher than "expected" ballpark so something is just not right.

Sounds like you recently replaced the rectifier but the comon way to damage those is to disconnect the outboard DC wires from the battery while the outboard is running. Might only take one time to pop the rectifier and a damaged rectifier could have high leakage current like you are seeing....???