Tidesmarine shaft seal Vs cooling water.

[Impaler]

I posted earlier about the mystery of where my exhaust cooling water was going. Running a 1GM10 out of the water with a fresh water feed to it no water was coming from the exhaust but plenty from the prop shaft. Awol rightly suggested squeezing the feed pipe to the shaft, this I did with a small G clamp. Had to squeeze it a fair bit but I the end the water started coming from the exhaust. Mystery solved and no blockages.

I guess the water took the easy route, I also suspect that some back pressure from the exhaust pushed it to the seal. Once afloat the seawater obviously provides sufficient back pressure to make it all function as it should.

That’s another afternoon gainfully passed.

 

[vyv_cox]

I posted earlier about the mystery of where my exhaust cooling water was going. Running a 1GM10 out of the water with a fresh water feed to it no water was coming from the exhaust but plenty from the prop shaft. Awol rightly suggested squeezing the feed pipe to the shaft, this I did with a small G clamp. Had to squeeze it a fair bit but I the end the water started coming from the exhaust. Mystery solved and no blockages.

I guess the water took the easy route, I also suspect that some back pressure from the exhaust pushed it to the seal. Once afloat the seawater obviously provides sufficient back pressure to make it all function as it should.

That’s another afternoon gainfully passed.

As I pointed out in the original thread, the 'back pressure' in the shaft is a couple of inches of water when the boat is stationary and possibly zero when it is moving. It seems to me that you may need a restriction or orifice plate in the flow to the seal to ensure that the exhaust hose does not go up in smoke.

I am not really sure why the shaft seal needs a supply. Normally yachts only need a vent pipe, my PSS is perfectly happy plumbed in this way. Different for fast mobos but presumably your 1GM is not installed in such a craft??

 

[Impaler]

As I pointed out in the original thread, the 'back pressure' in the shaft is a couple of inches of water when the boat is stationary and possibly zero when it is moving. It seems to me that you may need a restriction or orifice plate in the flow to the seal to ensure that the exhaust hose does not go up in smoke.

I am not really sure why the shaft seal needs a supply. Normally yachts only need a vent pipe, my PSS is perfectly happy plumbed in this way. Different for fast mobos but presumably your 1GM is not installed in such a craft??

Well the system was installed brand new by CC and has worked perfectly well for two seasons and I am sure will again. The feed pipe has a small ID, certainly less than 10mm so I’m not going to mess with fitting an RO and probably messing it all up. The seal manufacturers stipulate a water supply. Indeed, I’d be lucky to exceed 6kts under power. ️

 

[superheat6k]

As I pointed out in the original thread, the 'back pressure' in the shaft is a couple of inches of water when the boat is stationary and possibly zero when it is moving. It seems to me that you may need a restriction or orifice plate in the flow to the seal to ensure that the exhaust hose does not go up in smoke.

I am not really sure why the shaft seal needs a supply. Normally yachts only need a vent pipe, my PSS is perfectly happy plumbed in this way. Different for fast mobos but presumably your 1GM is not installed in such a craft??

The PSS does not require a forced water supply below 12 knots, but a vent above water line is recommended to allow air to vent out without burping.

 

[MoodySabre]

Vyv’s website has a pic of the Tides Seal on my boat and the cautionary tale of what happens if that water feed fails. The seal overheats very quickly and becomes seriously damaged. I subsequently changed to a PSS which has fine for six years with just a vent tube.

 

[Impaler]

Tidesmarine specifies a water flow and I’m certainly not going to remove that. Hopefully we will all be allowed to sail before too long and will see how it goes.

seriesOne Shaft Seal Installation | Tides Marine