2004 F75 Yamaha not charging consistently

[wishin i was fishin']

Hi all! Long time reader, first time poster. Anyways, my outboard charges "good" about 20% of the time this year. Charged great when I put it up in the fall. Sometimes itll charge great after a high speed run but sometimes not so much. Ive only made short fishing trips and I always charge my batterys but I have an on board charger that charges my trolling motor battery off the Starting battery when the the Voltage is over 12.7v i believe. I dont think this is the problem. All connections are tight. Dont know much about the outboard but I have a decent mechanical knowledge.

thanks for any help!!
Brent

 

[rodbolt]

Re: 2004 F75 Yamaha not charging consistently

use a digital multimeter and some jumpers,check the volage at the starter while its running and compare it with the helm guage, also double check your battery connections for cleanliness and tight connections.