50hp mercury thunderbolt (Battery, wiring or motor issue)

[theshoaibahmed]

Hi all friends

By you helping me i fixed the carburetor on my 50HP mercury outboard motor.

But i notice this morning, when i took the 14' boat suddenly it wont start. My sixth sense told be that motor should ok so i decided to change the current marine battery with my new marine battery fully charged which was connected to my trolling motor. After connecting it. Motor start right away and fish finder not giving me messages"low voltage" after an hour or 2, seems i start seen "low voltage" message again. So i decided to cut my fishing tour and see if one of you guys can help me out, what could be the iaaue. After motor start battery should be keep charging. (this is my understanding)

What you guys suggest

 

[racerone]

Test the charging system.----What is actual voltage on battery with motor stopped ?----What is actual voltage on battery with motor at fast idle ?

 

[theshoaibahmed]

Thanks racerone

I dont know anything about what you mentioned above, if you or some one guide me through. I can get through that just like i build the carb. with helper in this forum.

What i need and how to check to check the charging syatem.

Thanks

 

[Texasmark]

Go to Harbor Freight and buy yourself a $6 Digital Multi-Meter. Get it unpacked, per the provided instructions get the battery and cables in/with the unit installed and connected. Go to your boat's battery. Set the range-function selector to 20 volt DC range. Turn it on. Measure the battery terminal voltage. It should be around 12v. Record the number.

Assuming you are at home, attach muffs and adequate water for cooling and start the engine. Run the rpms up to ¼ max and read the same terminals on the battery. If your reading hasn't increased up to 13volts or so on the meter...amount depends on rpms and battery charge condition, you have charging issues with the engine.

 

[theshoaibahmed]

Go to Harbor Freight and buy yourself a $6 Digital Multi-Meter. Get it unpacked, per the provided instructions get the battery and cables in/with the unit installed and connected. Go to your boat's battery. Set the range-function selector to 20 volt DC range. Turn it on. Measure the battery terminal voltage. It should be around 12v. Record the number.

Assuming you are at home, attach muffs and adequate water for cooling and start the engine. Run the rpms up to ¼ max and read the same terminals on the battery. If your reading hasn't increased up to 13volts or so on the meter...amount depends on rpms and battery charge condition, you have charging issues with the engine.

Thanks Texasmark

Ill try that, i live in canada, toronto so i have to do it all by myself