6.2 MPI Whine noise when revs

[Pacfanweb]

Okay, this is a 2001 6.2 MPI. You can hear a whining noise when you're up in the boat with the hood open. It's definitely abnormal. Boat did not make that noise when it was winterized.
We thought it was a power steering pump, sounds just like a power steering whine from up in the boat. Replaced the pump, got it running today and I had my son down near the drive to make sure the earmuffs stayed in place when I was bleeding the air out of the system.
Noise was still there. Then I revved it up a couple of times, and he says it's really loud at the back of the boat. And he was right. So here it is in a video, it gets louder the warmer the engine gets. Is worse at the end. Almost sounds like a turbo spooling down...which would be really cool if it had one.
Any ideas?

 

[Scott06]

Okay, this is a 2001 6.2 MPI. You can hear a whining noise when you're up in the boat with the hood open. It's definitely abnormal. Boat did not make that noise when it was winterized.
We thought it was a power steering pump, sounds just like a power steering whine from up in the boat. Replaced the pump, got it running today and I had my son down near the drive to make sure the earmuffs stayed in place when I was bleeding the air out of the system.
Noise was still there. Then I revved it up a couple of times, and he says it's really loud at the back of the boat. And he was right. So here it is in a video, it gets louder the warmer the engine gets. Is worse at the end. Almost sounds like a turbo spooling down...which would be really cool if it had one.
Any ideas?

Pull the drive check u joints and gimbal bearing did u have water in bellows over the winter ?

 

[dubs283]

When was the last time the drive was removed for service?

Being louder outside the boat I'd be suspect of u joint/gimbal bearing issues

FYI rapid throttle increase with quick return to idle with no load can lead to valvetrain issues

 

[Pacfanweb]

Pull the drive check u joints and gimbal bearing did u have water in bellows over the winter ?

It was all replaced last year. It's been to the lake twice since it was repaired.
Had gimbal, bellows, shift cable, fuel pump, plugs/wires/pickup, impeller pump, and a few other things. It wasn't making this noise when I winterized it, I'm about 99% sure.

 

[dubs283]

Regardless of last service that whine and apparent rattle in the video denotes something quite off

First step is to remove the drive and inspect u joints and gimbal bearing. If okay I'd be suspect of low oil in the drive. Would think the problem will be obvious after inspecting these items

 

[Scott06]

Regardless of last service that whine and apparent rattle in the video denotes something quite off

First step is to remove the drive and inspect u joints and gimbal bearing. If okay I'd be suspect of low oil in the drive. Would think the problem will be obvious after inspecting these items

Agreed on this path forward.

 

[Pacfanweb]

Regardless of last service that whine and apparent rattle in the video denotes something quite off

First step is to remove the drive and inspect u joints and gimbal bearing. If okay I'd be suspect of low oil in the drive. Would think the problem will be obvious after inspecting these items

Okay, sounds like the first step is actually to check the drive oil, lol, before doing all that work.
I do recall now that when I first opened it up, the oil reservoir was low. Didn't take much to top it off, though. I believe the Bravo 3's do consume a bit

 

[Scott Danforth]

Okay, sounds like the first step is actually to check the drive oil, lol, before doing all that work.
I do recall now that when I first opened it up, the oil reservoir was low. Didn't take much to top it off, though. I believe the Bravo 3's do consume a bit

No, first step is remove the drive and inspect the bellows, gimbal bearing, u-joints, and alignment. that task is done every 50 hours or annually

if you need to replace the u-joints, you have to open the drive up anyway. no sense wasting gear oil

also, Bravo drives dont consume any gear oil. if your oil is going down more than thermal expansion and contraction. you have a leak.

 

[Pacfanweb]

No, first step is remove the drive and inspect the bellows, gimbal bearing, u-joints, and alignment. that task is done every 50 hours or annually

if you need to replace the u-joints, you have to open the drive up anyway. no sense wasting gear oil

also, Bravo drives dont consume any gear oil. if your oil is going down more than thermal expansion and contraction. you have a leak.

Okay, all that stuff is brand new. I'll talk with the shop that replaced it. They are very backed up or it'd already be over there, I'm just trying to see if it's something less involved that I can do.
It did not make that noise the 2 times it went to the lake after the repairs, nor when I had it running when winterizing it. Kind of odd.

 

[Scott06]

Okay, all that stuff is brand new. I'll talk with the shop that replaced it. They are very backed up or it'd already be over there, I'm just trying to see if it's something less involved that I can do.
It did not make that noise the 2 times it went to the lake after the repairs, nor when I had it running when winterizing it. Kind of odd.

Had the same thing on my old boat a few years back- ran fine when winterized, made a similar noise when back in in the spring. Gimbal bearing was bad, had some water in bellows , bearing gets corroded while it sits. U joint could do the same thing.

Did you have a lot of water in the bilge at some point? high water in the bilge can also fil the bellows with water

 

[cyclops222]

Tight bearing somewhere.

 

[Pacfanweb]

Had the same thing on my old boat a few years back- ran fine when winterized, made a similar noise when back in in the spring. Gimbal bearing was bad, had some water in bellows , bearing gets corroded while it sits. U joint could do the same thing.

Did you have a lot of water in the bilge at some point? high water in the bilge can also fil the bellows with water

No, the plug was open the whole time, it had 2 covers on it and doesn't really get wet.

 

[alldodge]

Try this it's real easy, simple and only takes a few seconds
Large flat tip screw drive and back out the top vent plug on starboard side of drive

Back it out slowly until you can get some drive lube come out of the plug. The lube should be greenish and thick.

Don't worry if a bit much comes out because the drive lube bottle will replenish it. Want we're trying to find out is if the drive is actually full of lube

 

[Pacfanweb]

Try this it's real easy, simple and only takes a few seconds
Large flat tip screw drive and back out the top vent plug on starboard side of drive

Back it out slowly until you can get some drive lube come out of the plug. The lube should be greenish and thick.

Don't worry if a bit much comes out because the drive lube bottle will replenish it. Want we're trying to find out is if the drive is actually full of lube

Just checked, it's full and the fluid looks good

 

[Scott06]

Just checked, it's full and the fluid looks good

One thing to try have you done the same revving but at different drive angles via both trim and steering. Willing to bet it changes pitch which would be an indication of gimbal and or u joint issues despite the previous work

 

[cyclops222]

My turbo Honda Accord suddenly made sounds like a real turbo.
Warranty replacement of a bad bearing in the turbo. New turbo by Honda.

 

[Pacfanweb]

One thing to try have you done the same revving but at different drive angles via both trim and steering. Willing to bet it changes pitch which would be an indication of gimbal and or u joint issues despite the previous work

Well, I just picked it up from the shop last August. It only went on the lake twice.
Didn't make this noise either trip, and it definitely didn't make it when I was winterizing it in November. So somehow in just over 5 months this noise has cropped up.

Among other things, some of the work done was replacing all the bellows, a new sealed gimbal bearing, shift cable, trim senders, oil monitor hose, outdrive mounting o-rings. Verified alignment and did some wiring repairs. And a bunch of other unrelated stuff. So hopefully I will have some warranty on this if it's one of the parts he replaced

 

[Simoniz]

.

 

[Scott06]

Well, I just picked it up from the shop last August. It only went on the lake twice.
Didn't make this noise either trip, and it definitely didn't make it when I was winterizing it in November. So somehow in just over 5 months this noise has cropped up.

Among other things, some of the work done was replacing all the bellows, a new sealed gimbal bearing, shift cable, trim senders, oil monitor hose, outdrive mounting o-rings. Verified alignment and did some wiring repairs. And a bunch of other unrelated stuff. So hopefully I will have some warranty on this if it's one of the parts he replaced

Yeah we have been through what work was done and how this can happen over the winter. I suspect you will find either water got in bellows or water got in the gear lube and corroded a bearing in the drive.

 

[Pacfanweb]

Yeah we have been through what work was done and how this can happen over the winter. I suspect you will find either water got in bellows or water got in the gear lube and corroded a bearing in the drive.

It's fine. The noise I hear in the engine compartment is the new fuel pump. The noise from the drive is just the helical gears whining as it winds down because it is unloaded and out of the water. I'm actually out on the lake right now and it's perfect. I talked to the mechanic and he had already listened to my video and is pretty sure that's what it was. After driving and I agree, it does not make that noise out here.
False alarm I guess. I swear I don't remember that whining but driving around in the lake it's fine it doesn't sound any different or feeling any different.