Volvo Type Stern Seal with Water Feed

[Jokani]

New to me boat, the shaft seal, which I understand was only fitted a few months before my purchase:



I thought this was a Volvo seal, but after a bit of Googling, I think it is a 'Volvo Type Stern Seal with Water Feed, as advertised on the T Norris Marine website.

I am struggling to find any installation or maintenance instructions online, can anyone help with that?

Three bits I am particularily interested in:

1. Is the manufacturer/ model other than 'Volvo Type'?
   
   
2. As it has a water feed, I guess it does not need burping?
   
   
3. It has what appears to be a nut/bolt that can be removed and used to insert grease, so I guess that it does not need the 'straw method' that some people use to inject grease in to Volvo dripless seals?

TIA

 

[tillergirl]

I would suggest you ring Norris. I always found them very helpful and pleasant.

 

[jwilson]

Both Vetus and Orbitrade sell seals like this. I have been told Orbitrade in Sweden made the seals for Volvo and later started selling their own modified version with water feed. It could be the Vetus one is sourced from the same company.

 

[VicS]

New to me boat, the shaft seal, which I understand was only fitted a few months before my purchase:

I thought this was a Volvo seal, but after a bit of Googling, I think it is a 'Volvo Type Stern Seal with Water Feed, as advertised on the T Norris Marine website.

I am struggling to find any installation or maintenance instructions online, can anyone help with that?

Three bits I am particularily interested in:

1. Is the manufacturer/ model other than 'Volvo Type'?
   
   
2. As it has a water feed, I guess it does not need burping?
   
   
3. It has what appears to be a nut/bolt that can be removed and used to insert grease, so I guess that it does not need the 'straw method' that some people use to inject grease in to Volvo dripless seals?

TIA

There is some information about "Volvo" seals, and several others, on Vyv Cox's website
Stern glands

Google will find the instruction sheet for Volvo seals

 

[rotrax]

My Orbitrade seal looks very similar.

On mine the pipe is a bleed tube which is fixed about a metre above the waterline and self bleeds the seal after lifting or drying out.

I am unaware of a water feed type.

 

[ithet]

I thought the extra tube on these was to vent air (as described on the ASAP website). That is to vent air rather than burping so that the water in the stern tube can lubricate the rear lip seal. Rather than as a feed to drive water past the seal the other way. It is not a moot point, if it is able to do the latter then I could use one of these to replace the VP seal and separate stern tube feed on my Beneteau.

 

[Mistroma]

My Orbitrade seal looks very similar.

On mine the pipe is a bleed tube which is fixed about a metre above the waterline and self bleeds the seal after lifting or drying out.

I am unaware of a water feed type.

Yes, the tube is meant to allow air to escape and doesn't need burping. My old Southerly had a cutless bearing with water feed. It made sense as we often motored slowly with the keel up and bearing pretty close to mud and sand being stirred up. The water inlet was further forward and well away from the prop.

I can't see much need to pressure feed a Volvo type seal. It's too far inside the stern tube for much grit and shouldn't generate enough heat to merit pressure cooling. It would only be worth doing if the water then found it's way to a cutless bearing that did need a pressure feed.

Edit: Just spotted ithet's post. I started mine 1/2 an hour ago but my wife arrived home and wanted some help with something. I posted my comment and now see ithet has a situation that could benefit from a combined feed.

 

[Tranona]

You are right. Remove the plug to grease. You can do this afloat as it is behind the lip seals so no water comes out. The feed can either be a water feed or vent, the former usually for higher power/speed boats, and yes, needs no burping. I have the similar RMTA seal made by Radice but just use the tube as an air vent to well above the waterline

 

[vyv_cox]

I thought the extra tube on these was to vent air (as described on the ASAP website). That is to vent air rather than burping so that the water in the stern tube can lubricate the rear lip seal. Rather than as a feed to drive water past the seal the other way. It is not a moot point, if it is able to do the latter then I could use one of these to replace the VP seal and separate stern tube feed on my Beneteau.

I have the same arrangement for my PSS seal. Just a vent to ensure the faces are always wet. They suggest that power boats may require a pumped flow but sail boat speeds do not

 

[Jokani]

Thanks for all the advice much appreciated, I'll just top up the grease.