Rattle Noise in Bravo1
 

Hi, I found a lot of drive oil inside my bellows so i brought my drive to a merc mechanic. He said it was the seal and he replaced it. He also replaced the u joints since the drive was off the boat anyway. Yesterday i started the boat up on a hose and noticed a rattling sound that i never heard before coming from the upper housing area. After doing some research i noticed that there is a procedure to adjust the rolling preload on the bearings.. If the preload was incorrect can it make a noise like this?
what else could it be?
note. Drive is spinning in gear looks like it is just rocking back and fourth..not the case just shows that way in video

https://www.youtube.com/watch?v=au6xujfCaOk

https://www.youtube.com/watch?v=jWcaYPjrQBU

Geez, sorry I don't have the answer but any noise from the drive is normally not good. Did you tell the Merc Mechanic about it? That would have been my first call.

He checked it out and said it sounds like a u joint because it got louder when turning the steering. We removed the drive and one u joint was binding a bid tight... Hopefully that was it

Your prop in the first vid is rocking back n forth, this would have me think the gears were not timed and its slipping between FWD/REV

Noticed that too...that shouldn't happen under any circumstance.

Something is wrong inside the drive. The U joints wouldn't make any noise with the drive level to the hull.
You did refill the drive with oil right.
If the noise gets louder when you turn the drive it is probably because you are side loading the input shaft.
I bet the input shaft bearings are bad.

The drive in the video was in gear...The prop is spinning...I found the video strange also showing that...looks like it is rocking...not the case here

never had a noise in that drive before the seal was changed...It was quieter with the oil seal leak

There is a u joint that seems tighter than the other, that's being changed today ..oil level was where it supposed to be.. filled with Amsoil marine drive gear lube..(great stuff)..input bearings bad? or not put back together correctly??

My drive has an OF starting part of the serial#. It is back from 2003 year I believe 2nd gen. How do you know if the input shaft bearing pre-load is 5lbs rolling or just tighten to 80 lbs torque..Is there a way of telling?

Rolling torque is set between 6 to 10 in Lb for manual 11 (first gen) and manual 28 (2001 and up)

Other then maybe a bit more noise, I know of no way to tell. In adjusting you need to use a new lock nut. Pic is from manual 11 but is the same as 28 and can be adjusted without being in the husing

[ATTACH=CONFIG]566784[/ATTACH]

I don't think he used a new lock nut.....I found some info on youtube but i think it was an alpha..You just tight the nut to 80lbs...He said he set it for 5 to 6. We are going to check it today.
Is it possible he didn't set it right and its loose inside? With the drive all the way in and straight its hard to believe the noise is the u joint

I've never seen anything from merc that was "hard shimmed"....it can ( and I've done it) be done though.

was the drive shaft that slides into the engine coupler,, greased,, or dry when you removed it after the rattle noise, if it is installed dry and not greased it will rattle loudly., and rattle more when the steering wheel is turned .
if he set the rolling torque at 5-6 in.lbs.,,that will not make noise ,,unless the bearing are bad.

Alpha 1 Gen 2 preload is 8 in lb
Alpha 1 R and MR used a spacer (item 6) and were torqued to 80 ft lb. If gear sets were changed the spacer was not used and rolling torque was set at 6 to 10 in lb

[ATTACH=CONFIG]566791[/ATTACH]

Took it apart...Checked the rolling pre-load first it was at 10..going right and 5 going left...something is out of round..removed nut and washer, bearings not turning smoothly. Large washer next to seal and ring has a rough spot in center. metal to metal worn seems like pre-load was set too tight and/ or spanner nut over tightened With an 18" torque wrench set at 120 should give a 200lb torque as manual says.I don't think a torque wrench was used.(the cause)..He is changing the bearings etc.assembly I feel better now at least we found something

Good deal, be sure to post the root cause so we can all learn.

when a drive is level with the bottom of the hull the U joints are straight and so is the input shaft so no noise.
Like I said something is wrong inside the drive.

Update...They found a inner washer that looks like it was rubbing against something.. see pics... Probably from over tight pre-load adjustment and/or as stated before no torque wrench used only the spanner tool and a hammer. Putting drive back on tomorrow and start up. Hopefully noise gone..
[ATTACH=CONFIG]566810[/ATTACH][ATTACH=CONFIG]566811[/ATTACH][ATTACH=CONFIG]566812[/ATTACH][ATTACH=CONFIG]566813[/ATTACH]

And WHERE did all of that metal go???

Did someone that specializes in Bravo drives do the repair this time?
I find it hard to believe that lack of proper torque would cause that to happen.
The only way that could happen is if something were missing or something were installed in the wrong order.
Unless this time it was serviced by a drive expert I wouldn't run it until it is.

That wear is the byproduct of the pinion bearings losing their preload, seen it many times, that washer goes between the input yoke and the front pinion bearing cone, once the preload starts to go,
The pinion can wiggle around, from the load being applied to it, the washer isn't compressed any more and is free to spin, further amplifying the issue.

Good question..This washer is located between the 2 bearings that are pressed onto the gear and the seal at the other end. It is considered a inner washer No metal filings were seen in the carrier and the input shaft and components, bearings, spacers were disassembled inspected and cleaned before re-assembly. I use Amsoil marine gear lube that is a clear drive oil..After draining the drive and removing the magnets nothing was seen. That washer has a groove in it when new. It only ran for 10 minutes at idle..It probably would have been worse under load

I agree...The person that originally worked on it was Merc..certified But..could have put that washer in the wrong way..It was assembled by a different person this time an expert in drives..

JaayTeee.. So your saying that the pre-load wasn;t set tight enough or the old nylon lock nut backed off. I made sure they used a new lock nut this time

Thanks I will relay this

That wear is what I've seen after a drive had a bit of time on it, not something that was just put back together ( after seal/
u-joint replacement) and not ran for a very long time, no less, not under load....my guess is that washer wasn't replaced.

If they did put the washer on backwards that would explain a lot of things...the washer is stepped, the step goes inside of the bearing, you flip that around, the shaft won't be able to go in as far as it should....probably not even far enough to get to the elastic part of the nut.

interesting he probably had the beveled washer in wrong
I found this to be helpful also
https://www.youtube.com/watch?v=c0SlzpJBhEM&t=467s

I agree, the spanner nut did not do that, it was ran with no rolling preload torque on upper pinion bearings,

Ok.. Drive back on..Started her up and ...No rattling noises...Apparently it was little to no pre-load and that worn washer ....I appreciate everyone's help

NEW UPDATE....SAME PROBLEM...Took the boat out for a short ride last weekend...Prior to that I decided to change the complete input shaft just to be sure...Re set the rolling pre-load with the drive oil on bearings to 6 inch lbs..Book says 3 to 7 used bearings...Used a torque wrench as the manual says to, tighten spanner nut...Torque wrench set for 120 @ 18" long with merc spanner tool @ 12" long gives you a torque of 200 ft lbs.Put drive back on boat. Started her up nice and quiet... As previously stated went for a 1 hour ride.. Kept rpm's under 4000...NO issues.. Got back to the marina put the boat back on the trailer. I always rinse my motors, Started her up and that same rattle noise was back 2 fold....Louder than ever.. We install another new seal, lock nut and red locktite. How can it be loosing preload???
Need help Please???

Have you listened to someone else's drive out of the water ? If not, will be a good idea for a reference.

Easy..Started the other engine..no noise from the drive at all

Sorry you had to witness my brief battle of sometimers. :)

No Prob. I had a noise at (sometime) on the other NOW quiet drive..It wasn't as pronounced as this but sounded like a rattle coming from the upper. I never did anything about it and it seemed to go away. The merc mechanic at that time said it was a resonating sound from the engines cam and the sound being under the back of the boat...Of course i never agreed but its been fine since....

Bummer, thought for sure you had it this time out

Is the Coupler greased heavily,, if dry or very light grease they will rattle

Ok, They took the drive apart today and checked the preload on the input shaft bearings..It was holding at 5.5 inch lbs. They took it all apart again and checked the bearings and then re set the pre-load for 7.. Looking further hey did find the drive shaft bad. It is the shaft that sits in the center of the top and bottom gear along with the cone clutch. That shaft doesn't spin in neutral but the top and bottom gear do with the bearings that sit on the driveshaft. Hopefully that was the noise i heard...There goes another $400:cartman:

Hope they remember to set the timing marks correctly

I even know how to do that now...lol

I would say if the rattle was coming from the coupler my spline on the input shaft would be bad and /or the coupler spline and the noise would be inside the boat. I was told that when you grease the coupler it is only for the spline so it moves freely when trimming, turning etc
I always put a lot of blue merc grease on the spline when re-installing my drives