Water in DPH U-joint bellows – immediate problem?

A_8

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During pre-launch checks today I found water inside the U-joint bellows on my Volvo Penta DPH drive. The drive was dismantled and had its full 5-year service last year.

At the end of last season there were no noticeable vibrations or unusual noises, but there’s clearly been some water ingress. I’d estimate around half a deciliter came out – it was clear, with no rust coloration or oil residue.

I haven’t removed the drive yet and would appreciate some advice on how to approach this once I do.

Would you typically:
  • Dry it out, re-grease and run it for a season, or
  • Assume the U-joint/bearings may already be compromised and replace as a precaution?
I’m aware the bellows can get damaged during pressure washing, so it’s possible this hasn’t been run extensively with water inside. That said, the water did taste slightly salty.

Any input or similar experiences appreciated.

Thanks
 
With so small amount of water I doubt the bearings have been affected, the U/J should move in all directions smoothly, if notchy or very stiff its damaged. Rotate the shaft to feel for roughness in the bearings, again should rotate smoothly. Take out the drain plug at the bottom of the drive to see what colour the oil is, should be clear golden colour, if its milky then water has got into the drive. If all is goid refit bellows making sure the bead inside the lip sits in the groove on the drive and on the transom.
 
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Thanks, I checked the oil last year and it was clean – it’s drained now anyway.

I opened everything up today and luckily the U-joint moves smoothly in all directions with no roughness, so that’s reassuring. Plan is to clean it up, let it dry out for a day, then reassemble with a new bellows.

It turns out whoever mounted the drive last year hadn’t seated the bellows properly on the transom, exactly as spannerman pointed out.

The sealing surface/bead is a bit distorted now, so I’ll need to tidy that up before reassembly.

Appreciate the help 👍
 
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