Starter getting only 4 volts

[sparklingwaterbubbles]

I have an 85 HP Force outboard. The starter is relatively new, and the battery is brand new. I went to start it after about two weeks, and it struggled to crank over.

I took the starter out and had it tested. Disconnected from the boat, it works flawlessly. The battery itself reads at 12.5 volts.

I re-installed the starter and ran it directly to the battery (positive and ground), and it is only getting 4 volts. Still struggling to turn. It is also arcing, throwing sparks where I hook the positive jumper cable to the red cable on the starter.

This is a new one for me. Does anyone know why this kind of thing would happen? And are there any usual culprits for this on a Force motor?

 

[alldodge]

Cables are the issue
Look real close at the ends and look under the insulation at terminal lug. My guess is there is corrosion under the lug and insulation

 

[sparklingwaterbubbles]

Cables are the issue
Look real close at the ends and look under the insulation at terminal lug. My guess is there is corrosion under the lug and insulation

Which cables do you mean? When you say lug and insulation, I assume you mean the ground cable from the battery? Would that affect it if I’m going straight from the battery to the starter? I’m bypassing the main ground cable.

Thank you for your response. I’m so lost here.

 

[Nordin]

As alldodge says check all cables, terminal lugs and grounding.
If you try to run the starter direct from the battery with jump cables with clamps you have to have really good connections to the clamps and large connection area.

 

[dingbat]

Would that affect it if I’m going straight from the battery to the starter? I’m bypassing the main ground cable.

DC current flows from positive, thru the starter windings and back to ground.

As such, both the positive and negative cables must be properly sized to load. Using a large diameter positive cable and a smaller ground cable will reduce the current flow through the circuit to that of the smaller cable.

Any corrosion on or inside the cable and or on the terminal post will reduced the current capacity of the circuit as well

To test the cables, remove the ends of the cable from the battery and starter. Put your voltmeter on ohms and touch both ends of the cable. A “good” cable should be 1.0 ohms or less. A reading above 5 ohms is a problem

 

[jerryjerry05]

New battery could be bad? Load test it.
The cables could be bad?? Check for swelling along the length of the cables and bad connectors.
New starter- the "new" starters from China are famous for being or going bad right out of the box. I've found that rebuilding the OEM is the best way to go, use Mercury parts when possible.
Next: compression test, pull the plugs and try turning it over??

 

[racerone]

Take starter apart !-----Inspect test it.----Take ohm reading on armature.----If bad you have the smoking gun.----Guess work on outboards often does NOT work and gets expensive.

 

[cyclops222]

No load testing is useless / worthless with the high current draw of the starter motor engaged into the flywheel. If you read 4 volts on the big lead posts of the battery while cranking ? Battery has a serious problem.