Light problems

[JakexPie]

Well, I have been trolling this forum for a while and finally bought a boat. I bought it about a week ago and everything was already pre-wired. Everything comes down to one positive and negative lead. I found out that yesterday when the motor is running and I flip the toggle for the lights it drains power from the motor. I loose rpms and it slows down. But if I flip the toggle for the bilge it does not drop the rpm's. What could be the problem??? I thought that maybe the stator cant handle the draw, because it is a 1975 johnson 25hp, but wouldnt it do the same thing when the bilge was turned on?

Thanks
-Jake

 

[Wallijig]

Do you have vom to see how much current you are drawing with each? To compare current draw from lights to bilge.
With out a meter, I would try unhooking lights, then hook them up one at time. See how many before problem occurs.

If have alot of lights drawing to much current, one could switch to LED lights which would draw less current.

 

[donmac]

I'd charge the battery, leave the motor powered off, then troubleshoot your wiring problems. If it is a an old home built job it may be a lot easier to just rewire it. You may find that the battery is toast. Your lights should not impact your motor.

 

[JakexPie]

How would I go about using a VOM to check it. And its only the bow and stern light, can you get those in led?

 

[Buddychrist]

On my SeaPro I have all of my electronics, lights, Fishfinder, etc. on a separate battery

Have you thought about buying a second battery to run your bilge, lights, trolling motor, etc?

They are fairly cheap ~$40 for a battery that will last for an all day or all night fishing trip

 

[Wallijig]

How would I go about using a VOM to check it. And its only the bow and stern light, can you get those in led?

Yes lights are available in LED.
To check with VOM Hook wire in series set to amps turn on switch see draw.
Here's basic video how to check current:
https://www.youtube.com/watch?v=yrpmq2FCnqs&feature=fvwrel

I agree with Donmac I would check battery first. Only way it would affect motor is to rob all it's juice for ignition, which would be unlikely if have good battery.

 

[JakexPie]

I tried two different batteries. Does the motor use the battery after it is started. If not how is it drawing power and lowering rpms? Im soo confused.

 

[Wallijig]

I tried two different batteries. Does the motor use the battery after it is started. If not how is it drawing power and lowering rpms? Im soo confused.

Motor should not need battery to run, only to start.
Sounds like you may have issues with motor electrical system.
I would check voltage across battery before start and after start. It should increase once motor is running.

 

[Buddychrist]

The motor should run without drawing power but it is still a good idea to have your motor and electronics on a separate battery that way you will never have to worry about having enough juice to get cranked up and go home

 

[astonblake]

i think you should change your light with led and that will take low charge.you should review your power system.problem may be created for old machine.

 

[rusty.hook]

I agree with the above posters about running all electrical items including troll motor on a separate battery, should not ever have a problem again. On the other hand if they drain your new battery then you have more electrical problems that need to be replaced or repaired.