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Post by ForGrinsToo on Feb 25, 2021 19:32:19 GMT
A recent article suggested that it would be a good idea to mount a second, high-capacity bilge pump at some level above the standard water-level-controlled pump (diaphragm in my 36i, with hose into the sump). This would be separately switched (and fused) and for use when the need demands. It seems like a very good idea. I'm looking for thoughts, particularly from 36i sailors who may have done this, on where and how.
Geoff
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Post by dbostrom on Mar 3, 2021 9:46:43 GMT
A recent article suggested that it would be a good idea to mount a second, high-capacity bilge pump at some level above the standard water-level-controlled pump (diaphragm in my 36i, with hose into the sump). This would be separately switched (and fused) and for use when the need demands. It seems like a very good idea. I'm looking for thoughts, particularly from 36i sailors who may have done this, on where and how. Geoff I think I've told this story here before but... A guest crew on our boat passed by the fuel dock on returning to harbor. The attendant asked them "what's all that water coming out of the transom?" Due to a maintenance bobble (crossover between "who is tightening this clamp?") raw water was spewing into the bilge while the engine was still being cooled adequately. The crew had managed to turn off the bilge alarm, and the absurd little factory box-ticker bilge pump had jammed a valve on a "foreign body" (stripped wire insulation fragment-- watch those!). Subsequently the secondary pump kicked on when the water rose above the sump quite a bit, saving damage to our inverter and numerous other bits that would otherwise have been flooded with salt water. I wasn't on scene to see the flow rate but it's possible this could have become a truly serious situation, without the secondary pump. The box-ticker was replaced with a high-capacity bait well pump happy to pump crud. But the point is, the secondary pump was really good to have. $180 of pump, switch, tubing saved a large amount of grief and much more money. One other point: if you read enough incident reports you'll notice a trend: rarely used bilge pumps tend to become clogged with detritus accumulating in bilges just when they're needed most, because detritus from the entire bilge gets picked up in these rare events and transported to the pump inlet. An ample, generous screen around the secondary pump is a must, to create better luck. Here's a photo from our 39i which probably is close enough to your boat. Location was determined by non-disruptive tubing routing options. Following Jeanneau scheme, tubing leads back to transom with additional fitting through hull. This is a nominal 8,200 l/h pump which in this installation will pump something like 5,500 l/h. Size tubing as large as possible. If you don't have and don't plan on having forced air heat, the factory duct for heating leading behind the galley/refrigerator/etc. will handle tubing nicely. Power is supplied via breaker and switch at nav desk panel, the switch normally being in "auto" but with a manual option for the case of a failed automatic switch. Be sure to include an indicator lamp for when pump is operating, as an additional situational information resource. [screen not in this picture but easily made from perforated stainless, our case this www.onlinemetals.com/en/buy/stainless-steel/0-06-thick-x-0-5-hole-x-0-6875-stagger-stainless-perforated-sheet-316-round-hole/pid/24893 and in the shape of a large cylinder around the pump, with a hole for tubing exit]  |
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Post by ForGrinsToo on Mar 4, 2021 20:24:24 GMT
Thanks. That is exactly the sort of information I sought. We don't have plans to heat, so I wondered if the ducting was a good idea as it leads nearly to the transom.
Geoff
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Post by dbostrom on Mar 4, 2021 22:46:36 GMT
That air duct is very helpful as a conduit, if not used for its intended purpose. It passes behind the galley where access is extraordinarily difficult. There is a factory conduit passing back there but it is much smaller and not suitable for pushing tubing through.Given the frame/floors arrangement, below the sole and back is not a possibility without insulting the frames pretty badly.
The other route is just straight across and out the side, but I feel as though there's a good reason why Jeanneau chose to route to transom as they expended precious build dollars pursuing that, didn't want to second guess.
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