OK,
I'm getting thoroughly confused on this nylon barbed fitting on the seal and the instruction pages don't seem to clear it up.
The yard installed one of these seals on my '84 E-28 (3/4" shaft) as part of some general engine compartment work I'm having done. Decided to spluge on this system since the tightness of the original stuffing box arrangment did not allow enough room to remove packing, only to squeeze in a little new packing. Also, with this boat's extremely shallow bilge, eliminating any water intrusion is a plus. Yard's dropping the engine back in this week but I'm wiring and plumbing it back up, including the addition of this barb.
Instructions seem to say it's OK to feed it water from the raw water circuit after the heat exchanger (where it's been warmed a bit by the closed loop system) and before injection into the exhaust elbow. My boat has an antisiphon loop before the exhaust water injection elbow which uses a 1/4" bleed line run aft to the transom where a small stream pees out while the engine is running. Perfect. Tap off that with a 1/4"-1/4"-3/8" reducing tee and run the 3/8" hose to the 3/8" fitting on the seal.
However, this board (and the manufacturer) indicates you don't even need this fitting for under 12 knots. Wish I knew before the yard ordered it that you can special order one without a hose fitting. I assumed that meant I could possibly cap off this fitting and not have to run extra hosing.
Checked with the manufacturer and laid out my plans and questions. Following is their response (quite a prompt response by the way).
Thank you for the email regarding your PSS Shaft Seal.
You will wish to keep the top of the vent hose open. This will prevent any air from being trapped in shaft log / seal area.
Please feel free to call me with any questions at: 800-523-7558.
Best Regards,
Dan Schalk
Manager - PSS Shaft Seal Division
Huh? :unsure: I've asked for a clarification. I assume the manufacturer knows what he's talking about but I worry about possible misunderstanding in our communication so looking for some feedback from Vikings with this system.
Wouldn't leaving this fitting open release water into the boat? I would think the two options would be either to pipe water to it or cap it off, not leave it open.