Water in the outdrive

[Loyd Dinneen]

I am curious where water can enter the outdrive oil when all I have done is run it with muffs, it hasn't been in the water yet. I have earlier replaced the carrier seals, Shift shaft seal,and the waterpump complete from bottom to top. The lower was pressure tested and passed with no pressure loss.
I have the whole drive off now and have separated the upper and lower and replaced the upper seals and it looked like the lower waterpump area had some exhaust intrusion. What I did notice is when I removed the outdrive the last person who had worked on it had not put on a new housing gasket(there was really not one there only sealer and parts of the gasket)and the water o-ring looked old and was flat and hard. Would like to figure this out before reinstalling the outdrive, I have put new bellows in and the large square o-ring(it was installed with silicone sealer before) and the u-joint bellows were full of old grease and the gimbel bearing was shot (replaced it). Basicly I have rebuilt the standard stuff and don't want to go back into it again for a long while, so please help me find out where this water came from. Another clue is the water wasn't mixed into the oil very much but ran out clear when I pulled the bottom plug about a 1/2 of a cup and the oil was missing almost the whole qt there was only about a pint left. I did notice that the bottom plug had a double gasket on it and at one time some oil was coming out of the prop exhaust area but the not the carrier seal(replaced). My merc mechanic said it was overflow from some area when we had filled it after doing the lower repair. Please any response would help me figure this out.

 

[northern]

I used to have OMC twin stern drives. There were seals between areas and some were vertical and others horizontal. When run on land if you force water into the leg it is like being in the water. Mine got replaced every 100 hours as they were milky oil at the end of the season.

 

[Loyd Dinneen]

I had only ran this outdrive (I have twin mercruiser pre alphas) a couple of times because I was having trouble with it shifting into reverse.(was missing the stainless washer I found out) So I removed the outdrive to check it out and found all the other issues. Tomorrow I am going to take the outdrive over to my merc guy and we are going to pressure test it to see if it is leaking anywhere. All the seals have been replaced so unless I had gotten a bad seal it should be fine, unless murphy bites me in the rump with bad luck. I really want to get this in the water and go fishing and cruising have never owned a boat this large and I'm excited to spend some nights on it and away from noisy Vegas.

 

[Loyd Dinneen]

Took the outdrive to my merc guy and pressure tested it and there was a leak, so took it back home separated the two halves and reset the waterpump with another base o-ring and took it back to the merc guy and retested the lower end. Yep we found the leak to be the shift shaft seal (could of sworn we replaced it when we did the waterpump). A fast trip across town with 2 mins to spare got a new one and back to his shop and we installed it the now the lower holds pressure. I only hope that will solve the water issue and I can get onto other stuff. Now I have to put the two halves back to gether and get it back on the boat.

 

[Soulshine]

I used to have OMC twin stern drives.

My last boat had twin OMC stern drives.

I don’t miss them and I’m guessing that you don’t either.

 

[Loyd Dinneen]

I wanted twins for the security of having a spare engine to run but it has been double trouble with these out drives and having to repair them because the last person did everything wrong when working on them. Now I wish I would of purchased a boat with outboards much easier and safer to run, mean while I will try to get it in the water after shift adjustments. Almost ready to take it to a Mercruiser dealer to let them finish it up so I can get it on the water, have had it here for 9 months and 4 months working on just the mechanics part of it the rest squaring away the looks and getting it back to 1977. I have rebuilt the carb on one, replaced the trim tab solinoid on the pump, pulled both out drives and put in new waterpumps, seals, gaskets,bellows,and gimbel bearings all because the people before didnt believe in housing gaskets only silicone sealer.