1989 88 spl starter barely turns flywheel

[Buckeyedude]

Hello all! Im pretty sure I need to order a new starter from what Ive read, but would appreciate some input. Here is a rundown of the my situation. Last year I never got to use my boat. Had it out in the yard and ran it with muffs on several times before parking it back into my shop. (always use rec 90 with starbrite stabilizer,Johnson/rude oil and a water separating filter in the line) Brought it out this year to hopefully get some fishing in. Hooked the muffs up, cleaned the plugs and a couple of turns later she was purring! Ran it for awhile, on off, idle, throttled up etc. The next night, I wanted to run it some more, but this time it would barely turn thr flywheel and the starter would stay up. I ended up finding a plug wire that had been separated from the boot almost like someone yanked it off. So anyways, I get a new one ordered, put it on and Im back in action. Motor runs like it should. Fast forward a week, I go to run it some more and Im back to it barely turning the flywheel and the starter staying up and acting like its hurting for juice.
Here is what Ive checked so far. Battery full charge. All wires and connections seem in good shape, clean and tight. ( Im going to go and recheck them just in case I missed something after im done typing this). I ran a meter on the starter and had someone turn the key for me and Im only getting 10v on it.
Any ideas or input is welcome and appreciated!

 

[saltchuckmatt]

The plug wire typically gets ripped off from the boot when somebody puts the cowling on not knowing that it's hooked on the plug wire. I just did it to one yesterday.

I typically get about 10 points something volts to the starter after it passes through all the things, personally, I think it's easier just to take some jumper cables and jump the starter and work your way back.

It's usually a bad wire, solenoid or you may have just gotten a bad starter. Undervoltage or lower voltage will also ruin a starter.

This should be fairly easy to diagnose, and hopefully you can get it diagnosed quick so they can get back out on the water and have fun.

If you need more help on how to jump the starter let me know.

 

[racerone]

Have battery load tested.

 

[cyclops222]

Your battery is probably run down because of......NOT ENOUGH .... running the boat in real water. Racerone load test will probably cost you a new battery. Really rundown batteries are are a pain to correctly recharge.

Can you bring the boat and car next to each other ? Jumper the batteries correctly. Will tell you if the boat needs a battery.

 

[Buckeyedude]

Thanks guys, hoping to have some time to work on it this afternoon!