Mercruiser 383 Mag Stroker -Issues Lake of the Ozarks MO

[michaelpkcmo]

I have a 2016 merc 383 mag stroker with bravo 3 installed in a 2004 Rinker 282 Captiva.

My issues are as follows:

2 weeks ago:

I was running the other day at 4500 rpm and i heard one loud bang type noise from the engine compartment. I immediately slowed to engine down to 600 rpm idle speed. No warning lights or sounds were observed or noticed. Since there was some debris on the water I assumed that the noise was from the lower unit hitting something.I then proceeded back to my boat dock about 2 miles away. I ran the boat at about 4200 rpm back to the dock. The motor didnt seem to want to run as fast on the way back. It didn't seem like there was much speed left after 4000rpm. When back at the dock I observed the bravo 3 unit and it doesn't appear to be damaged on the outside. Once the boat got close to the dock it died. It didn't want to easily start up; but after 2 attempts it did start up. The idle appeared to be a bit lower than 600 rpm idle speed once it started

This weekend:

I took the boat out for a ride. The Battery seemed low and didnt want to easily turn the engine all the way over. I replaced the battery and the starter seemed to have more energy. While driving the boat it seemed to lag in power and i couldnt get it to go past 4,000rpm. On occasion it would randomly speed up to 4400 rpm but would then slow back down eventually without moving the control lever.

Once back at the dock I turned off the engine. When i tried to start it the starter appears to spin really fast but wont engage the engine flywheel.

My questions are as follows:

Am i supposed to hear a beep once it turn on the ignition before i start the engine?

What would the 1 time oud bang noise would have been? Would it have been the starter going bad. If so why would it go bad while at 4500 rpm? Is that why the starter will not engage now to turn over the engine? Is the starter controlled by the 555 ECM?

Is there some type of warning horn, beep etc which would have limited the engine speed so that it is now sluggish and wont go past 4000 with the control all the way forward? Would the ECM slow the engine down if something is wrong?

Could this be a problem with the bravo 3 drive?

All help is greatly appreciated as this is my first mercruiser inboard boat.

Thanks.

Mike in KC

 

[alldodge]

What's the engine serial number?

The starter wouldn't have caused the bang

 

[Bt Doctur]

oil pressure, engine temp, outdrive oil , how are they?

What would the 1 time oud bang noise would have been? Would it have been the starter going bad. If so why would it go bad while at 4500 rpm? Is that why the starter will not engage now to turn over the engine? Is the starter controlled by the 555 ECM?

The bank could have been almost anything, Unlikely a starter going bad because once the engine is started the bendfix retracts off the flywheel. A free spinning starter can be from a broken bolt/block/housing./broken bendix /broken ring gear.
Starter is mechanically controlled ,nothing to do with electronics.

Is there some type of warning horn, beep etc which would have limited the engine speed so that it is now sluggish and wont go past 4000 with the control all the way forward? Would the ECM slow the engine down if something is wrong?

Depending on your engine there should be a hard alarm for engine temp, loss of oil pressure and loss of drive oil.
Depending on your model, there is a "Guardian Mode" to reduce engine power

 

[michaelpkcmo]

Oil pressure normal range 60
engine temp 140
outdrive oil looks normal full
engine oil looks normal and full

are the broken pieces starter related or engine related?
How hard to repair?