Does this stuffing box have anything user serviceable inside?

[JayH]

Originally Posted by 4arch

I don't want to hijack this thread but my boat has the same Volvo shaft seal and the same water supply hose feeding the stern tube (see bottom of the photo). The water supply hose connects to a nearby thru hull and ostensibly supplies water to lubricate and cool the shaft log. This is a pretty common setup on Beneteaus but I've always wondered whether it was strictly necessary. I've asked around but have never gotten a straight answer out of anyone. I've seen the Volvo seal installed on many boats without this feeder hose and I'd really prefer to eliminate it and get rid of the fitting on the stern tube, which has no way to be closed if the hose were to leak.

This is from a different manufacturer, but still applies:

Q. Do I need water lubrication?
A. At hull speeds of 8 to 10 knots and above, a vacuum is created in the stern tube that draws the seawater used for cooling and lubrication. At slower hull speeds, no water lubrication is necessary. The supply hose can instead be used to purge the air out of the seal when the vessel is put back in the water. If there is no water injection, ensure there is water to the seals at all speeds. Lasdrop does, however, recommend water injection for all seals and speeds.

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[Qayaq]

Originally Posted by 4arch

I don't want to hijack this thread but my boat has the same Volvo shaft seal and the same water supply hose feeding the stern tube (see bottom of the photo). The water supply hose connects to a nearby thru hull and ostensibly supplies water to lubricate and cool the shaft log. This is a pretty common setup on Beneteaus but I've always wondered whether it was strictly necessary. I've asked around but have never gotten a straight answer out of anyone. I've seen the Volvo seal installed on many boats without this feeder hose and I'd really prefer to eliminate it and get rid of the fitting on the stern tube, which has no way to be closed if the hose were to leak.

If your boat does 12 plus knots... surfing maybe...the stern tube can vacuum causing air to drag down through the lipseal and cause the seal to air lock and run dry, lip seals only work in one direction. IE stop the water coming up from the tube but not stop air going down the tube.I think the hose is there as an air bleed.
I really like these seals and done a lot of miles on them, Volvo sell the tooth paste tube of grease separately and I grease mine at every oil change.
Incidentally on a friend's boat he ran it dry due to a launching air lock as he forgot to burp it and it started dripping but not catastrophic failure, we wrapped a cable tie around the outside where the seals are and tightened it, he got a few months out of it before re hauling

[Emouchet]

Eventually after some years, the rubber dries out.


It is mandatory to change it before its too late. 5 years, 500 hours according Volvo.


Mine was fairly old when I bought the boat. It broke while i was in the process of burping it. It broke right after the locking clamp, with big water ingress.
Thanks god we were still in the travel lift...

[Pete7]

Just to add to the fun, Orbitrade who I think make the seals for Volvo also have one with a water feed

Whilst I can understand the need to avoid using petroleum based greases on a rubber seal, who says the volvo seal is made of rubber? Have to admit I have been using Keenol for years on our Volvo Seal without problems. The only problem now is Duckhams have dropped the Keenol grease which is a shame.

Pete

[Draughty]

My boat had one of these when I bought it 14 years ago; only started dripping after I pulled the shaft out a couple of years ago so I replaced it with another the same; cheap and simple and in my case the only one short enough to fit between the shaft log and the half coupling. Don't know why the hose; water gets in up the shaft log for lubrication. No mention of any need for forced water supply in installation instructions, but they do say don't use a flexible coupling between gearbox and half coupling.