Water feed to shaft seal.

[Heckler]

Yes, a common method on Beneteau motorboats. The grill is shaped to act as a scoop although you still need to burp the seal to eliminate an airlock. Do check that thru hull though. The hose tail on the ball valve was brass, as fitted by Beneteau, and with only light pressure it crumbled (seriously dezinced) and water started to pour in. My natural reaction was to shut the ball valve but the water continued to pour in! I then realised that ball valve was of no value at all as the water was coming the other way from the prop tube. Luckily I was on board but if this hose tail had failed when I was not, even if the ball valve was closed, the boat could have sunk.

Www.solocoastalsailing.co.uk

My thru hull had a reducer which crumbled! Luckily on the hard!

 

[Birchwood33]

I really like the idea of a raddice rmta seal, so it has a grease cap and a vent tube attachement, no need for direct water tube?

 

[vyv_cox]

I really like the idea of a raddice rmta seal, so it has a grease cap and a vent tube attachement, no need for direct water tube?

I cannot speak for all seals but certainly for the PSS and I imagine most others there is no need for a pumped supply in yachts whose speed does not exceed about 10 knots. A vent is perfectly adequate to lubricate the faces with water.

 

[Tranona]

I really like the idea of a raddice rmta seal, so it has a grease cap and a vent tube attachement, no need for direct water tube?

I am just about to fit a Radice, and although it is in a sailing boat will run a water feed because the stern tube is very long with a bearing at the inboard end as well. Probably not strictly necessary, but running a vent above the waterline is difficult.

Your name suggests a largish MOBO and a water feed may be a good idea. Beneteau and Jeanneau use the Volvo seal on their MOBOs and use a water feed, although in their case it is to the inboard end of the stern tube, but it does the same job of ensuring no air in the tube or seal.

 

[Plum]

.... Beneteau and Jeanneau use the Volvo seal on their MOBOs and use a water feed, although in their case it is to the inboard end of the stern tube, but it does the same job of ensuring no air in the tube or seal.

Yes, and on the ones I have seen, that water feed is provided by a forward facing scoop type skin fitting.

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