clicking sound at mid-RPM's. Gen-1 drive, 165 HP

[CaptainMak]

After a hard run, dropping RPM's to about 1500-2000, I hear clicking sounds at the stern. I boat with kids and wife, so getting an accurate location is nearly impossible.

The clicking sounds are identical to a starter bendix engaging and its erratic. Any suggestions where to start looking would be great.

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

That could easily be a chipped gear tooth in the top box. Drain the oil, remove the top cover and turn the engine slowly while looking closely at the gear teeth...

Run into any sand bars lately?

Chris......

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

That could easily be a chipped gear tooth in the top box. Drain the oil, remove the top cover and turn the engine slowly while looking closely at the gear teeth...

Run into any sand bars lately?

Chris......

Not that I know of, but one of the prop blades was a bit chipped towards the end of last season. The top cover - you mean the one with the hook eye ?

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Yep, and that means it's an MC-1, more prone to chipping gears than the later drives....

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Thanks Chris.

From what I can see in Manual #2, Section 6A-14, I should be able to see both gears, the "Drive gear" and the "Driven gear" on the upper shaft if I remove the top cover. If the drive is all the way down, do I still need to drain all the oil out of it ?

Also, are these replaceable and easy to find IF this is the problem ? Can an average guy replace these himself ? Thanks again.

 

[dubs283]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

If the drive is all the way down, do I still need to drain all the oil out of it ?

Also, are these replaceable and easy to find IF this is the problem ? Can an average guy replace these himself ? Thanks again.

drain all the lube, check it for metal flakes/chunks

the gearset is replaceable but you need special tools to shim the new gears

before you go that far, the erratic rhythm of the noise could also be your exhaust shutter rattling, use a mechanics stethescope or long handles screwdriver to listen at the exhaust pipe with the engine running to narrow down the source of the noise

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

drain all the lube, check it for metal flakes/chunks

the gearset is replaceable but you need special tools to shim the new gears

before you go that far, the erratic rhythm of the noise could also be your exhaust shutter rattling, use a mechanics stethescope or long handles screwdriver to listen at the exhaust pipe with the engine running to narrow down the source of the noise

Not at 1500-2000 rpm.. At idle yes, but not that high. I'd also venture to speculate that an engine of this vintage ain't got no shutter left....

Chris......

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

the erratic rhythm of the noise could also be your exhaust shutter rattling, use a mechanics stethescope or long handles screwdriver to listen at the exhaust pipe with the engine running to narrow down the source of the noise

It doesn't make the noise at idle nor do I hear it when it's on muffs when I throttle it for a brief period. Seems to be more of an occurance after a hard run. I'll try to check out those gears and report back.

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

OK,
drained the oil, took the top cap off. The gears look clean and shiny, no irregular pitting, scratching, etc. The oil is slightly brownish, but mostly green.

There are definitely no chipped or missing teeth.

What now ? :yield:

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

any other ideas what it could be ? the starter solenoid can't be doing this while the engine is working ?

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Can you video the noise and past the video? Also is there any regularity, and does it change with engine speed?

Chris......

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

I'll try to record the noise next time we are on water. There is no regularity with it. Very sporadic, sometimes 2 or 3 clicks in a 5 second interval, sometimes 1 or 2 in a minute.

Are there lower gears too just like the upper has ? Could it possibly be those ? What do noisy lifters sound like ?

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Yes there are lower gear, but you wouldn't hear a noise from them. Usually a noisy lifter will be more regular...

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Here's a video I found on YouTube that has the same sound that my engine has. It's that clicking noise when some throttle is given.

Merc 350 Ticking Sounds - YouTube

 

[CaptainMak]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

sorry for the BUMP,............

 

[achris]

Re: clicking sound at mid-RPM's. Gen-1 drive, 165 HP

Yeah, sorry about that. I posted a reply yesterday, just as the server crashed... Obviously it didn't make it to the board.

The sound in that video is very much like pinging (fuel or timing problem). You can say it sounds like yours, but that was a V8, you have an in-line. So without hearing your engine, I can't say...