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speed2lead
06-10-2004, 08:37 PM
Have 80 hrs. on both motors, just had the second gear box failure due to the shift shaft seal pushin out. It was the port engine 2 months ago and now its the starboard engine same thing. What would be the cause of this seal pushin out? ANY SUGGESTIONS?
time warp
06-10-2004, 09:05 PM
Typical 3.0 litre gearcase problem, Lakeland Marine in Lake Havasu has the remedy, they have a billet shift shaft seal carrier that holds 2 seals. The problem is that running surfacing these gearcases create a lot of pressure and cause that seal to leak oil out, then when you stop the water cools the gearcase down it creates a vacuum and sucks water back in through the leaking seal, water in gearcase not good.
Lakeland Marine (928)453-1155
they have a website www.mercspeed.com
From the what's new page,

New Billet 300 Pro Max shift shaft seal perch, for 3.0L Sportmaster...two seals. A Lakeland Exclusive!!!

They are around $60-70 each but are the best fix I've seen for this problem.

Tell them Caleb from Washington sent you.


You probably aren't going to get Mercury to put them on under warranty for you but maybe your mechanic could put them on the new gearcases for you.
I'd get them unless you are going to get another year of warranty.

Good luck,
Caleb
sosmerc
06-10-2004, 10:03 PM
It takes like maybe 3 minutes to take a small sample of gearlube, then top of the oil level and replace the little seal washers. I do this before every outing. I don't mind the hassle, especially since I haven't yet had ANY gearcase failures.
Yes, I know, this is not practical for anyone that keeps their boat in the water. In that case, all I can say is, check your gearoil whenever possible. Always change the little seal washers on the screws. Use Mercury's high performance gearlube.
Shift shaft bushings are a weak spot in ALL Mercury gearcases.
It's the nature of the beast. Maybe the new Verado will also have a better gearcase design...and that will filter down into the smaller motors.
Thank goodness, progress is slow. That's what keeps me busy all year round!!