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Old 11-17-2017, 11:04 AM   #11
diver dave
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City: Palm Coast, FL
Vessel Name: Coquina
Vessel Model: Lagoon 380
Join Date: Jan 2017
Posts: 2,570
Yeah, I've been one on the unlucky ones with PSS. My fault, but still a failure at sea. I didn't dimple/drill one of the shafts to allow the coupler set screws to work into. My bad.... ulitimately, the shaft moved forward about 1" and the PSS seal "disengaged" causing a rush of water. And, of course, the other possible failure mode is a loss of cooling water for planing boats, causing seal melting, etc. Bad, bad.

What follows is the Buck-Al fitting sizes in the 2 to 3" range for the box. That 2nd number is the packing size, so I'm using that to describe the worse case ring of ocean, that is incoming. There is quite a range in there from 5/16" to 1/2" So, if you did a conversion to PSS type seals, then you might want to do the further calculation of max incoming sea, when the worst happens. I would maintain that a 3/8" circle lets in much less water than a 1/2" thick circle of 3 1/2" circumference. Yes, the volume depends on depth, which for a 72 might be 5' deep, not sure. Yep, a bunch of water is coming in. Would I put in another PSS system? Not sure, but in my last vessel, I was getting real tired of the salt misting around a lot of steel and iron hardware, which the PSS does solve. For sure, I'd design the pumping system to accomodate a huge leak there! And the mention of a melted boot is rather an interesting puzzle to solve at sea!

00sL200fg 2'' 3/8'' 3'' 4-3/4'' 2-3/8'' 18.00
00sL225fg 2-1/4'' 7/16'' 3-1/2'' 5-1/2'' 2-1/2'' 21.00
00sL250fg 2-1/2'' 5/16'' 3-1/2'' 5-1/2'' 2-1/2'' 21.00
00sL275fg 2-3/4'' 1/2'' 4'' 5-3/4'' 2-9/16'' 45.00
00sL300fg 3'' 3/8'' 4''
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