# Yamaha 90 hp starter troubles



## Artlow12 (Jun 8, 2018)

I am about to pull apart my starter motor on my '98 90 hp Yamaha to check the brushes on it, but before I do, I wanted some input. When I hit the key the starter rotates the flywheel around 1/10th of a turn, lags, and does it again. I had trouble getting home the weekend before I noticed this, but the starter was working flawlessly. So much so that I probably over ran it trying to get the boat home. My assumption is that I wore down the brushes inside of it.

Things I Have Done:​-Charged battery, battery tested at AutoZone​-Tried to have them test starter, but said they couldn't do it without a car model number.​-Tested starter with jumper cables and a battery, it seems to work with no load.​-Cleaned wires to starter and separate starter solenoid.​-Cleaned Pinion with parts cleaner and re-greased with spray silicone, tried to pull pinion off to clean, but couldn't get it off without breaking the key.​​Things I plan to do in the next few days:​-Try and check and see if there are any drops in voltage across the system.​-Replace my lower unit oil, just in case it is gumming everything up when it tries to start.​​Questions I have:​-Is a solenoid a (working / not working) part? Is there a chance of it starting to fail and having a big voltage drop across it?​-Has anyone rebuilt a starter motor, it seems pretty straight forward as long as none of the bolts are seized.​-Is there a good way to test the starter before I pull it all apart?​-I am assuming my motor is not seized as a week before, the starter was turning the motor over, and it will turn the flywheel some now.​​​


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## 17376 (May 5, 2017)

Nothing to do with LU bc it is in neutral...

Get a screw driver, turn the key to on position, and cross over the connection at the solenoid. If it fires up easy, starter is good. Then look to solenoid, wire corrosion etc. Try that and get back to us. I believe an older Ford solenoid will work for you if it's the solenoid. You can get one dirt cheap at autozone


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## fishnpreacher (Jul 28, 2018)

Pull the spark plugs and spin it wit a no-compression load, or try turning the motor by hand to see how hard the motor is to turn. It doesn't sound like a solenoid issue, but electrical problems will make you scratch your head and wonder


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## Artlow12 (Jun 8, 2018)

Good call on pulling the plugs. I am glad I did this before I started pulling the starter apart. Unfortunately, it appears that I have another issue with water getting into the system somewhere. Looks like I get to run down that rabbit hole.


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## fishnpreacher (Jul 28, 2018)

I'd be concerned with cylinder walls now. Borescope or tear it down...


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## madruga (Sep 29, 2015)

Take your starter off and take it to Central FL Remanufactory. They will test it for you for free and check it all out on the inside as well. Very honest people. They can either rebuild yours if it's bad or they can just fix what is wrong with it for less money and less warranty. 4072999011 in Orlando, FL


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## 17376 (May 5, 2017)

Don't worry about the starter. You ha e bigger issues.


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## ShaggyPalm (Sep 30, 2021)

I have a 2006 90 TLR that's not starting. I've pretty much rebuilt the fuel system and changed the spark plugs and still won't stay running. I'm at a loss at this point. Good luck


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