Water in UJ bellows.

tinkicker0

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Pulled the drive off this afternoon (merc alpha gen 2) for UJ, top bearing oil seal and gimbal bearing replacement.
As the drive came free, maybe around an eggcup full of water ran onto the grass. Aye from the UJ bellows.
Luckily no sign of terminal rust anywhere, but I now know why the gimbal bearing started growling.

Looks like it came up the shift shaft seal, filled the shift slide housing and then leaked past the big square section ring seal into the bellows.

When I changed the bellows last year, I noted the manual did not state exactly where this large O ring fitted in the housing, when I removed the drive last year it was missing, so no clue there; so I simply butted it up against the rear of the bellows and glued it in place.

Is this the correct location or too far forward, thus allowing water into the bellows area?

Fitting new bellows, UJs, top bearing seal, gimbal bearing and impeller this year and do not intend to have the boat lifted out again next year, so its imperative I get it right.

Thanks.
 
As you have recently renwed your bellows its obviously an installation issue rather than a worn or split bellow.

From your discription, you have the large square section o-ring in place although this can ocasionally get dislodged when refitting the drive, but if was still in place on removal then thats fine.

If your bellows are of the later type you will have an alluminium ring which holds the rear end of the bellow in place, the large o-ring butts up to that. If you have an earlier, jubilee clip at both ends type, then the large o-ring butts up to a shoulder in the gimbal housing, as you look up into the bellows.

If yor o-ring is where I have discibed then I would check that the ends of the bellow are seated correctly and that the jubilee clips are squarely installed and not p*ssed.

Another reason that you could have water in the bellows and duff gimbal bearing is that the engine bay has become flooded with rain water or similar and water has got in from the inside of the boat. As the seal does not work in that direction.

Hope this helps.
 
Thanks all.
It is the later type with the ally ring, which was fitted with the correct tool.
Can't discount bad installation, yet I have the drive at work now, got the driveshaft out and in the cleaning bath. No rust anywhere on the shaft, yokes or UJ spiders, so I'm a little puzzled.
The boat was in the water for 7 months, no sign of getting water in the bilge and as I say, no sign of rust, yet water in the bellows and a sh@gged gimbal bearing.

A strange one indeed.
 
Happened to mine (2x 290DP). Following a survey in which they were described as being in good condition, my current engineer found both of them split and one of my gimbal bearing knackered. UJ and everything else fine. I now change my bellows every 3 years even they look good.
 
To be on the safe side, I think you need to re-instal, otherwise you'll be walking this path again next season. If the boat is in my area (Poole - Lymington, occasionally So'ton) I can take a quick look, If not it maybe worth employing the services of your local engineer just make sure there is nothing a miss.

Just a thought. When installing the ally ring, it is easily done to push the bellows inside the gimbal housing, while pushing the ring inside the bellows. Even with the correct tool.
 
The new bellows arrived and I am viewing the supplied bonding tab with suspicion. It is a fairly hefty piece of stainless to get a good seal with.
Thinking of using a piece of stainless mig wire instead.

Since the boat never sees salt water I reckon it should be ok.
 
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