Rattle from outdrive area

[Jiminthekeys]

Ok I started noticing a rattle when turning while trimmed up on plane so I had thought it was worn ujoints. My mechanic replaced the worn ujoints and while in there I had him replace the gimbal bearing and bellows.
Took the boat out the other day and there is no abnormal sound when trimmed all the way down and driving or turning hard. However when I trim up just to even the 1/4 mark and make some tight turns on plane I get a horrible rattle that seems to mimic the rpm's. It goes away when I straighten out from the turn. This rattle will also produce itself when going straight on plane about 4000-4200rpm and trimmed up to 1/2 mark. This only is heard on plane! Is baffling me and my mechanic. What else could it be? Could the new ujoints be defective? I don't think they would be associated with a spinning rattle sound but rather a knocking if they were the culprit.
Any help would be appreciated!

 

[Jiminthekeys]

Re: Rattle from outdrive area

Also the engine is a 3.0L a mercruiser TKS in a 2007 sea ray sport. Attached to an Alpha I Gen II

 

[alldodge]

Re: Rattle from outdrive area

Ok I started noticing a rattle when turning while trimmed up on plane so I had thought it was worn ujoints. My mechanic replaced the worn ujoints and while in there I had him replace the gimbal bearing and bellows.
Took the boat out the other day and there is no abnormal sound when trimmed all the way down and driving or turning hard. However when I trim up just to even the 1/4 mark and make some tight turns on plane I get a horrible rattle that seems to mimic the rpm's. It goes away when I straighten out from the turn. This rattle will also produce itself when going straight on plane about 4000-4200rpm and trimmed up to 1/2 mark. This only is heard on plane! Is baffling me and my mechanic. What else could it be? Could the new ujoints be defective? I don't think they would be associated with a spinning rattle sound but rather a knocking if they were the culprit.
Any help would be appreciated!

I hope your mechanic checked alignment but many times some of the boat mechanics don't do anything you don't ask for. Check your engine coupler, to see if the bolts are tight to the flywheel. Also check alignment and if the coupler is worn, look to see if the teeth in the coupler is worn. Have someone with you and open the hatch while doing some of your turns and see if they can notice the issue.

 

[alldodge]

Re: Rattle from outdrive area

Have another thought, when was the drive lube checked and changed?

 

[Fun Times]

Re: Rattle from outdrive area

Also be sure your trim limit height and gauge settings are adjusted correctly just to be sure you are not over trimming at speed.

 

[Jiminthekeys]

Re: Rattle from outdrive area

Have another thought, when was the drive lube checked and changed?

I checked the alignment and my mechanic checked the alignment. It's good. Drive oil has always been changed once a year at minimum and never any water intrussion in it and it stays in the proper range on the remote lube monitor. When mechanic put drive back on after replacing ujoints, bellows, and gimbal bearing it got new lube and is not diluted and within normal level on the monitor bottle.

How can I check the couple bolts on the flywheel? Do I have to pull the engine to do that? I don't even think my 5 year old can squeeze back there to look! It's pretty tight behind that motor. Mechanic mentioned it could be the "Flex plate"? But he said he would be very surprised if it is... What is the flex plate and where is that? How do I check to see if that may be it?

 

[Jiminthekeys]

Re: Rattle from outdrive area

Also be sure your trim limit height and gauge settings are adjusted correctly just to be sure you are not over trimming at speed.

Checked the trim limit and sender. Gauge is reading properly and outdrive is not over trimming.

 

[Fun Times]

Re: Rattle from outdrive area

To help give you an of what the area looks like back there have a look at the parts catalog.https://www.mercruiserparts.com/Sho...ng&inbr=11669&bnbr=140&bdesc=Flywheel+Housing

Is the mechanic working with you a friend, service shop or mercruiser dealer?

Is the boat new to you? Did this seem to show up one trip out?

The reason i'm asking, though it's not impossible due to many things, it just seems a little unusual for the u-joints to be worn for an 07 boat.

Boats with stern drives usually wouldn't use the term flex plate as they have an engine coupler and fly wheel.

Flex plates

Yes to check the engine coupler and fly wheel bolts, the engine would need to moved forward or pulled out.

Is this rattle something you can feel as well as you hear?

If item #9 was to be loose it could produce a rattling sound as well.

Hope you'll be able to find this rattle soon, keep us up to date on your findings.

 

[alldodge]

Re: Rattle from outdrive area

With the coupler, my thought was to see if you can see any worn splines on it. If you can see nothing wrong, check and see if you can slip the inner part of the gimbal bearing out, that is if the slots are forward. If you can get the inner bearing slid out, put the alignment tool in and see if there is any play, don't push hard. If the slots are not forward it won't work.

http://i178.photobucket.com/albums/w241/Air_Alpheus/Boat Maintenance/Couplerfailures1.jpg

 

[Jiminthekeys]

Re: Rattle from outdrive area

The mechanic is a well known certified mobile marine mechanic.
I am not feeling any of the rattling just hearing it.
I have owned the boat for 2 years and this noise just popped up one day all of a sudden. The mechanic said it was very uncommon for the j's to be worn out with a boat that year. The rattle is not as bad after he replaced them and the gimbal bearing but it's still there...

 

[Fun Times]

Re: Rattle from outdrive area

The mechanic is a well known certified mobile marine mechanic.
I am not feeling any of the rattling just hearing it.
I have owned the boat for 2 years and this noise just popped up one day all of a sudden. The mechanic said it was very uncommon for the j's to be worn out with a boat that year. The rattle is not as bad after he replaced them and the gimbal bearing but it's still there...

Good to hear that at least he is honest and trying to help. Has he been on the boat for a ride along? You may have to go out on a calm weekday and look around the engine and listen for the sound while someone else drives at speed.

Also check your inbox message notifications at the top of the forum.

 

[Jiminthekeys]

Re: Rattle from outdrive area

We are planning on taking It out tomorrow afternoon so he can hear it.

 

[Jiminthekeys]

Re: Rattle from outdrive area

We are planning on taking It out tomorrow afternoon so he can hear it.

So I still have not been able to get the mechanic out on the boat. He's been a little over committed with his jobs and can't get the time apparently. I talked to him today again and he's saying the only other thing it could be since this is only happening at speed trimmed and turning hard or going straight at about 4000 rpm and trimming about 1/2 up is the yoke is possibly bad where it accepts the u joints. He also said the upper gears looked great when he inspected them during the joint replacement.

What do you guys think? The replacement u joints are the non greaseable type as well as the gimbal bearing if that matters any.

 

[Bondo]

Re: Rattle from outdrive area

So I still have not been able to get the mechanic out on the boat. He's been a little over committed with his jobs and can't get the time apparently. I talked to him today again and he's saying the only other thing it could be since this is only happening at speed trimmed and turning hard or going straight at about 4000 rpm and trimming about 1/2 up is the yoke is possibly bad where it accepts the u joints. He also said the upper gears looked great when he inspected them during the joint replacement.

What do you guys think? The replacement u joints are the non greaseable type as well as the gimbal bearing if that matters any.

Ayuh,.... I'm thinkin', Yer drivin' habits are part of the issue,....

However when I trim up just to even the 1/4 mark and make some tight turns on plane I get a horrible rattle that seems to mimic the rpm's. It goes away when I straighten out from the turn. This rattle will also produce itself when going straight on plane about 4000-4200rpm and trimmed up to 1/2 mark.

Why are ya runnin' the trim so high, especially in Turns,..??

 

[Jiminthekeys]

Re: Rattle from outdrive area

Ayuh,.... I'm thinkin', Yer drivin' habits are part of the issue,....

I don't think so Bondo. I have never driven this boat or run the motor in the tilted position and when running straight the most trim I've ever use was 1/2. I typically use 1/4 trim as that is what makes the boat ride good with no bow plowing. I never turn with more than 1/4 trim. I've been driving rescue boats for the USCG for 14 years so I know how they should respond and know when something is not right.

Why are ya runnin' the trim so high, especially in Turns,..??

I've never trimmed higher tha. 1/4 in turns. Sometimes I trim up to 1/2 not more than that running straight so te now is not plowing. 1/2 trim and wide open my RPM hit the normal range of about 4200-4500.

 

[Jiminthekeys]

Re: Rattle from outdrive area

Mechanic called me back last night. He's saying it's definitely an issue with the joint assembly. He's thinking somehow out of balance or spec. He's suggesting to replace entire assembly. Yokes, socket and joints as a new assembly. Says that should fix the issue. Also says it's no way that it could be the coupler, gimbal bearing or any of my gears. They are all good he claims...

 

[agallant80]

Re: Rattle from outdrive area

Every boat is different but I rarely go over 1/4 on my boat and never any place close to the 1/2 mark. Try to ignore the gauge and trim by feel. Put some tape over it if you have to. You should be trimming by what feels right anyways not by what a gauge says. The amount of trim will vary by many things (current, rpm, chop, speed etc).

 

[alldodge]

Re: Rattle from outdrive area

How many threads have we all seen where we tell the poster that the trim gauge is worthless, or it's for reference only? My trim gauge shows I'm 1/2 way when in reality it's not. Stop the engine after running and find the drive will come up a lot more before the limit switch stops it. I don't think we can have it both ways, though many of us try.

As for the problem, You get the noise on hard turns running on plane, it could be the hinge pin on the gimbal ring or as your mechanic stated.

 

[Jiminthekeys]

Re: Rattle from outdrive area

How many threads have we all seen where we tell the poster that the trim gauge is worthless, or it's for reference only? My trim gauge shows I'm 1/2 way when in reality it's not. Stop the engine after running and find the drive will come up a lot more before the limit switch stops it. I don't think we can have it both ways, though many of us try.

As for the problem, You get the noise on hard turns running on plane, it could be the hinge pin on the gimbal ring or as your mechanic stated.

I always only trim to the proper feel and ride of the boat. I was just trying to clarify how much I was possibly trimming by telling you all where the trim gauge fell into. I checked how much trim it actually is when the boat it out of te water on the lift and even all the way up it's not very much at all

 

[Bondo]

Re: Rattle from outdrive area

I always only trim to the proper feel and ride of the boat. I was just trying to clarify how much I was possibly trimming by telling you all where the trim gauge fell into. I checked how much trim it actually is when the boat it out of te water on the lift and even all the way up it's not very much at all

Ayuh,... The point of my comments is that Tight turns, 'n High trim, really don't go together, 'n is a double-wammy on the u-joints,...

Not that it really matters, til yer Mechanic can get his eyes on it, it's all speculation,.....

He can double-check his installation, 'n mic the yokes if necessary,...
I wouldn't just swap the whole thing, Hopin' it fixes it,... that's an expensive chunk of steel,...

Diagnose, then repair,...