Intermittent Start- Starter doesn't click

[Mini Yacht]

Hey guys! I hope you're having a better season than I am so far. I've been having an intermittent start issue for the past month. Most recently, it's been a no-start issue. When I turn the key, the alarm sounds for a brief moment, and you can clearly hear the fuel pump engaging. However, the starter doesn't even click or do anything.

2002 Sea Ray 185 Bowrider
4.3l Mercruiser 220hp - #0M300066
Transom - #0M290514
Alpha Gen II Drive - #0M406192

I've already replaced the battery for free and the new one reads 12.7v at rest on the multimeter. The sierra starter was replaced with a Mercruiser starter/solenoid, and I've made sure that the starter wires are tight and not corroded. I've disconnected all of the negative-grounds attaching the engine block, cleaned them all off with a file/sandpaper and reattached them. I've also bypassed the neutral safety switch based on some research on here, and that didn't seem to solve the issue either.

It appears that I'm getting 12v on "start" wire of the ignition when the key is turned, so I'm assuming that my ignition is fine. It appears that the problem is somewhere between the ignition, and the starter itself.

There is also solenoid directly next to the main circuit breaker at the top of the motor- when I jump those two terminals together, the starter will immediately crank. I've already tried replacing this solenoid with a brand-new one from Mercruiser, and no luck. But when I jump this solenoid, the starter will always crank. However, when I turn the key, nothing happens and the solenoid doesn't even click. It appears that one wire (red/violet stripe) always has 12v, and the other wire (yellow/red stripe) connects directly to the starter (I think).

I'm just about at my wits end with this guys, any help would be appreciated- I'll be checking this frequently! Thank you.

 

[scoflaw]

Do you have a connection from the start switch to the small red/yellow on the start solenoid. That's the trigger

 

[PlayDate]

Welcome to CSR!

You have already replaced the Mercruiser part that usually fails. That said, I believe you have a neutral safety switch on your shifter/throttle lever that prevents starting when the engine in gear. I suspect that is where the problem is if you have 12 volts on the purple wire. The purple wire energizes the fuel pump and ignition system and appears to be working properly. Sometimes you can jiggle the Shift Lever and it will start which is the best indication it needs to be adjusted or replaced.

Your Owner's Manual has the wiring diagram on page 23.

https://s3.amazonaws.com/srweb-pvt-prod-us-east-1-294962523550/static/owners-manuals/2002_185 Bow Rider_185_Bow_Rider.pdf

 

[Bt Doctur]

The slave needs 2 things to work . You already tested the main wire by jumping the 2 large lugs and the motor turned. From your key switch the yellow/red wire goes to the slave, take a jumper from the battery + and touch the small yellow/red . does the motor turn Y,N
If yes ,now connect to the battery neg and connect to the other small lug at the slave, Now test with the key switch. If motor turns your missing the ground lead for the slave.

 

[Bt Doctur]

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