Strange occurancy 04 Merc 225

[atta]

So the motor has been running great since the current rebuild. This weekend was no different until the last run back to the ramp.

I was running on pad like normal and then i hear a noise that sounded like gears grinding or the starter grinding the fly wheel. the motor slowed and died within 5 seconds of the noise. Cranked up and it ran perfect for another 5 or 6 mins and did the same thing again. cranked it back up and again it ran perfect, sounded great, and was running correct with no power issues and about 6 or 7 mins it happen a 3rd time. Cranked it back up and ran it to the rmp @ about 4500 rpm until i got into the canal and i opened it up and it didnt do it anymore.

Very Very strange to me. A buddy thought it could be the gear case slipping out of gear and the motor turning off for safety reasons. ANyone ever had this happen or heard the noise before. motor cranks and runs perfectly fine. havent heard the noise since the 3rd time it happen.

2004 Merc 225
SN:0T907162

[atta]

Yeah i know it has me stumped also. I changed lower unit oil last night and had no metal shavings or chunks in the oil. Maybe this is just a strange thing that only happened that day and wont happen again. Thanks to all who have looked :)

[dkennimer]

Could the hub be slipping?

[atta]

Brand new prop and hub. But if it was slipping indont think it would cause the grinding noise

[Rich Z]

I seriously doubt it fix its self. Better have it looked at by a trained eye.

[Savage]

I seriously doubt it fix its self. Better have it looked at by a trained eye.

So true.....^^^^^

[atta]

spoke to the mechanic who re did the motor and he is stumped also. im going out saturday and all next week so we will see. it cant be the motor (IMO) it is runnig to good. im thinking some kind f gear case problem.

the Gear lube tab you wrote in Savage is the color my gear lube was but there was no water in it. It didnt look like mustard as much as that pic did though.

[atta]

Update:

the gear line when changed did smell a little burnt and it was not a good looking color. Probably a dark green/darkish Brown. I’m thinking the seals are going out. Talked to a buddy who had the same problem with the motor dying but it still running perfect after restarting. He said his did the same thing for 3 months and then the lower unit finally blew out. He says the the grinding noise was me prolly hearing the “dog gear” since the prop was still spinning.

Gonna run it tomorrow and change the oil to see if it has any color and I’m sure that will be the tell tell sign

[mdtritn21]

If the seals were bad you'd have water in the lower unit and white looking oil. It could be the shift cable has stretched or is out of adjustment and is not shifting all the way into gear and allowing it to try to jump out of gear when your running.

[atta]

Boat ran great today. No noises, no dying, and running faster than normal under load.

I agree with with your assessment. Engine was just rebuilt so the cable could have slipped or something but it’s fine at this moment. Freak thing I guess/hope.

[atta]

Have fished 4 days straight in the new lower unit oil and changed it tonight and it looked great. Haven’t had the problem again since it happen. I did notice that the prop nut was loose and the prop had about 1/4” of play in it. I tighten it down and it’s stillnrunning good and motor is strong.

[dkennimer]

Have fished 4 days straight in the new lower unit oil and changed it tonight and it looked great. Haven’t had the problem again since it happen. I did notice that the prop nut was loose and the prop had about 1/4” of play in it. I tighten it down and it’s stillnrunning good and motor is strong.

Glad you found it.