120 hp v4 turns over slow?

[wilson750]

I got a free boat with an evinrude 120hp v4 on it. I hooked up a (fully charged) battery and the motor will turn way to slow for it to start. Pulled the plugs and tried it and its faster. I'm thinking it's the starter? Would a starter go bad and not let it turn fast? I even hooked up a hott to the starter and a ground to the motor to test if it would turn better that way. Nope still turns slow! So my question is do you think its the starter / starter brushes maybe? Or somthing internal?

 

[racerone]

Does the motor turn easily by hand , plugs out ??-----Yes I have said it many times , those starters are easy to take apart and repair / install new brushes.----I install brushes picked up at local starter / alternator shop at $ 5.00 a set.

 

[Barnacle_Bill]

It could be the battery, battery cables, solenoid or the starter. A voltage drop test will pinpoint the problem.

 

[wilson750]

I will try moving it by hand with plugs out. Even might try using a pull cord vs starter. Battery is fully charged. Even got my other battery out to try just in case. Guess im pull the starter off just to check it out since it's fairly easy to remove.

 

[emdsapmgr]

try jumping the starter direct from a known good battery with a set of automotive jumper cables. If it spins normally, check the key switch and the starter solenoid. If it still cranks slowly, pull the starter apart for inspection.

 

[wilson750]

try jumping the starter direct from a known good battery with a set of automotive jumper cables. If it spins normally, check the key switch and the starter solenoid. If it still cranks slowly, pull the starter apart for inspection.

Thanks Emdsapmgr, I already tried hooking a cable direct to starter.I'm going to pull the starter off next and check that.

 

[flyingscott]

What happend when you tried to turn it by hand.

 

[batman99]

My previous Force I20 engine cranked really slow as well. For it, I removed and disassembled its starter and was shocked. Full of dust and its brushes worn down to its cables. Replaced its brushes for $15 and it cranked super fast afterwards. If your boat is old, it might need new brushes, it might need thicker battery cables (especially if current cables full of UV cracks) and it might need "next size up" battery. Especially if you use same battery for other over taxing electronics. As a few recommended, I'd inspect is battery brushes first....