My lower unit starting making noise and vibrating badly when I put it in gear. The noise sounds like a grind. It runs okay. It idles okay. I pulled the prop off and the hub
has the little strips on it. One of them was loose and fell off. Would that be enough
to cause my problem? Or do I have a LU gear problem?
Thanks in advance. LK
If you are missing one of the damper strips it can rattle at idle and the noise goes away under load. I never noticed a vibration on mine with one strip gone. While you have the prop off pull the drain plug & check for metal filings in the oil. Definitely before you run it again have it checked by your technician. Finding the problem may save some very expensive parts & not leave you stranded.
2018 Z521L 250 PRO XS V8
Howieranger. Thanks for the quick reply. I have always had Merc's and changed my own LU oil because I bought used. This was my first brand new Merc and I have had the dealer change the LU oil since it's still under warranty. On the other Merc's I had
there were two screws to fill the oil. One on top and one on bottom. On this ProXs there is only one screw there. I have a stupid question. How do you change the LU oil
in these motors? Thanks again. LK
The bottom plug is behind the prop. Take the prop off and it will be in the bottom of the exhaust housing.
2017 Ford F-350 Platinum
2022 BassCat Cougar Mercury 250 ProXS 4s
Is there any reason these strips can't be re-glued onto the hub?
I just reglued mine. Haven't noticed any difference. I just did not want to lose them if I had to change a prop on the water...
I also reglued a couple of mine and bought a couple of spare strips in case I lost one.
2018 Z521L 250 PRO XS V8
Thanks I have a few to re-glue myself so glad to hear it will work.
The snubber strips can be reglued, OR you can purchase a new snubber-strip kit (the strips come with self-adhesive glue already installed).
Loose or missing snubber strips may cause a rattle at IDLE, when in gear... OR when decelerating.
There would normally be NO OTHER discernable rattle.
IF you have ANY other discernable rattle... I would HIGHLY recommend getting this in to your Local Authorized Mercury Dealer for PROPER gearcase diagnosis, as there could be a clutch dog, pinion gear, or bearing problem.
Dual Mercury Master Technician- for Mercury Outboards, Mercruiser and Mercury Racing at European Marine in Greenville, SC.
Still consider myself a "Marine Apprentice" after 48 years (learn something new every day).
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Thanks everybody for the replies. I have an appointment with the dealer.
I just wish I was closer to Greenville, SC.
Thanks Don for the help.
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