HELP! Water Leaking Through Transom in I/O Mercrusier HELP! Water Leaking Through Transom in I/O Mercrusier
Bass Fishing Home PageTM    Boats and Motors  


Boating Equip.
Tackle Shops
Fishing Acc.


Fishing Reports
BFHP Articles
Fishing News
Fishing Tactics
Places to Fish
Boat Ramp Stories
Other Topics
Other Fishing Topics
Swap/Sell (no boats)
Props 4 Sale

Boats 4 Sale
Saltwater Fishing
Striped Bass
Lure Making
OBX Wildlife Photos
More Politics

Boats and Motors

    HELP! Water Leaking Through Transom in I/O Mercrusier
from Mike D. (  
8/11/1999 5:08:00 PM


  Help guys. Water is leaking through the transom in my Mercrusier. I brought it in for an opinion, and they tell me the "gasket" which seals the outer housing is gone ("cork gasket or something of the sort") and, voila, water is leaking like a faucet into my motor well where the outdrive mates to the motor. Bottom line I'm told is to pull the motor, replace the housing and gasket, and reseal the unit. All this at a cost of "roughly $1,200.00 with parts and labor". Am I on the right track and, if this is indeed the problem, is the cost fair?? Thanks so much for all of the helpful advice. Mike.

Rate this message:
1 Star

2 Star

3 Star

4 Star

5 Star

   I'm no expert but... from Jeff W. (  8/11/1999 6:56:00 PM
 Before moving to Texas I did allot of boating on the Great Lakes where I/O motors are used more often than outboards. I have heard and seen this happen quite a few times. Some cases it was due to rats chewing throught the seal on a boat moored to a dock. Years ago it was about a $650 dollar job. I friend of mine here in Texas has a merc. outdrive and his seal to leaking. He was quoted $850 to fix it. Based on that, the $1,200 sounds a little steep. In addition, his seal is still intact, it was leaking where it attaches to the boat. The same person that quoted him the $850 told him that if it were his boat, and considering the nature of his leak, he would buy some silcone sealant and re-seal the rubber seat. This may not help you if your seal is torn or has just started falling apart.

Sorry I could not be of more help.

   OI seal leak from Skipper (  8/11/1999 7:21:00 PM

To me that sounds like a hell of a price for such an operation. I have pulled I/O on houseboats, and it is no problem to do. It is generally a 2 hour job. If you have good access to the engine, it should be no problem to do that yourself. If not you, maybe your regular auto mechanic. With all the liquid gasket products on the market, one of them should do the job. I think the last time we did the houseboat, we used the Blue Goo. There should basically be 4 bolts in 2 engine mounts, a housing that covers the coupling, and an exhaust pipe and a water pipe. The wire snake should come off with the motor. The house boats I have worked on all had 120 Mercruisers (a 4 cyl chevrolet motor). Some of the more modern ski rigs have v-6 chevys. 2 of us could manhandle the 4 cylinder out of the well. On a 6 cyl, you may need a cherry picker. The only think I happened to think of, if this is a house boat, it does have to be pulled and if 1200 includes yanking the boat and re launching it, then that would be in line.


   leak from Pat (  8/11/1999 9:25:00 PM
 I own a boat with an inboard/outboard and have had this type of problem before. You might want to check the rubber boots one the outside of the boat that connect to the outdrive. Not too long ago the small one for the shift cable had a split it and would leak water in really fast. Not that hard to change. Part was about $25.00. this may not be your problem but it is worth takeing a good look at.Check them real close. If you pull the motor your self make sure you pull the outdrive also and have the motor relined after reinstalling. If it is not line up right it will destroy your coulping on motor in about 5 mitutes. Know this from experience. Any questions drop me an email.


   bellows leaking from shane hite (  8/11/1999 9:47:00 PM
 hey mike,you are way to far here.the last guy was right.most of the time,the rubber boots ,or bellows between the transom and sterndrive rott or most good mechanics,this is a 2-4 hr job unless they have my shop we charge 350-450.00 and the motor does not have to be removed.mercruiser is a great unit and unless the transom of the boat has been hit(by a mack truck)they dont normally leak where the hsg. bolts to the transom. hope this helps. shane hite
   Leak from Esjay (  8/12/1999 7:19:00 AM
 Exhaust bellows and shift boot should be checked annually when the outdrive is pulled off (easy to do) and u-joints, etc. are lubricated and checked.
   Many Thanks Guys from Mike (  8/12/1999 9:10:00 AM
  Thanks guys! I did pull the motor myself after determining that the boots, etc, gimble housing were find. It's the gasket between the housing and the transom. A reputable Mechanic I was refered to said beings I did a good job of pulling the motor and outdrive, he'll charge me $300.00 to re-install to "gasket/seal", re-seal and re-install and align the motor and outdrive. I hope this info helps some others who may experience this problem. Thanks again for all of your kind advice!!!! Mike.



Can't remember your password? Click here!
Email Address:

Users with subscriptions can attach pictures to their comments by using the form at"




Advertising/Sponsor Information

Register to post messages and reports


Subscribers don't receive these ads

Fishing Reports
BFHP Articles
Fishing News
Upcoming Events
Rally Page
BFHP Surveys
Fishing Tactics
Places to Fish
Other Topics
Product Evaluations

Boat Ramp Stories
Trailers & Towing
Boats For Sale
Tournament Tactics
Striped Bass

Fly Fishing
Saltwater Fishing
Non-Fishing 2
Political Hook
Tall Tales, Fiction & Legend
Complete Listing of Boards
Copyright © WMI, Inc. 1995-2017. All rights reserved.
This message board created and maintained by: WebMasters International, Inc. (WMI) address mail to

WMI disclaimer
Privacy Statement