Troubleshooting Starting Problems on Yamaha 100 F

dpimike

Recruit
Joined
May 6, 2013
Messages
3
Hey gang,

I'm a novice when it comes to electrical, but I wanted to see if I could see if someone else has had the same problem. So here goes:

Yamaha 100 Four Stroke
New Battery
New Solenoid
Supposedly rebuilt starter in the past
Good clean connection from wires to battery and to engine

Problem:
When I try to start it, it does not click, make any strange sounds, just sounds tired - like it's trying to turn over but just doesn't have enough "oomph" to get there.
If I put the battery on charge, connect it to the cranking battery and crank it,- it starts like it should. Will run around the lake just fine. Then, when I get back, turn it off and go to start it again - nothing.
I usually check the battery to make sure it's topped off. Sometimes just trying to start it with no battery charger connected, it will suck down the battery by about 10 percent - to 90 percent. Then, once I top it off, hook up the charger - it cranks right up.
Also, if I set another cranking battery next to the one that's hooked up and use jumper cables to give it extra juice, it cranks right up too.
I can yank off the starter and have it rebuilt, but why would it work fine when there is extra juice, but not on a good 800 amp battery with full charge on it's own?

Any advice, similar problems that have been corrected, would be appreciated!!

Mike
 

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
8,877
Re: Troubleshooting Starting Problems on Yamaha 100 F

Sounds like bad battery or bad connection, you have to hook something up bypassing the connection to make it work.

Voltage drop test under load should show where the problem is
 

Silvertip

Supreme Mariner
Joined
Sep 22, 2003
Messages
28,762
Re: Troubleshooting Starting Problems on Yamaha 100 F

What size battery did you buy?
 

dpimike

Recruit
Joined
May 6, 2013
Messages
3
Re: Troubleshooting Starting Problems on Yamaha 100 F

What size battery did you buy?


It is an Interstate 800 amp battery. It was the biggest I could locate in my area. Shows good charge and cranks my other boat (with a bigger motor) just fine. I think I'm getting robbed of power somewhere in the system.
 

dpimike

Recruit
Joined
May 6, 2013
Messages
3
Re: Troubleshooting Starting Problems on Yamaha 100 F

I found the problem. Starter was hot to the touch with little cranking. Took it apart and some fiber insulation had come unraveled and looked like a black birds nest inside. Cleaned it up and we're off and running.

Thanks.



Sounds like bad battery or bad connection, you have to hook something up bypassing the connection to make it work.

Voltage drop test under load should show where the problem is
 
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