pro10is wrote:
You're definitely on the right track. That is pretty much how I installed my bilge pump. The bilge location just forward of the aft hatch is correct. The use of a low energy glue is correct, however, be forewarned that even low energy adhesives will have problems sticking to the polyethylene surface. I have to reglue mine about once a year. You'll need to rough up the surface as much as possible and check the adhesion regularly. The use of the wooden mount is clever and should help.
I used a
Rule LoPro bilge pump because of its low profile, but the one you selected should work too.
Here is where I mounted the bilge outlet. It works well. After 7 seasons, I've never had an issue with it. The use of a check valve is critical as you mentioned.
Be aware that the use of a bilge pump is for significant water ingress only such as from rough seas, a storm, or a hull or hatch leak. It doesn't help much for day-to-day fair weather use where just a little water enters. I still use a manual bilge pump or the rear drain plug for that.
There's no need to avoid the use of an automatic pump, the float switch works well and is reliable. And the pump can always still be activated manually. I use a DPST switch, one position is for automatic operation and the other is for manual operation. This way you have both options, which is better than either alone.
I assume you have a decent size sealed lead-acid or better yet a 12V lithium battery onboard which will provide enough run-time operation in the event of an emergency. It needs to be able to run the pump long enough to reach the shore. Be sure to recharge it before each outing.
That's all I can think of, please let me know if you have any other questions.
Thank you pro10is.
My main vetting here is location, conventional wisdom puts it as far aft as possible, but in a yak I think just fwd of the rear hatch is good and you too have confirmed this. I've seen some guys put them just aft of the center hatch of the AI's (humm?). The glue I've been using on HDPE that seems to work VERY good is Loctite 3035 Polyoflen. It's not cheap at about $50 a tube. The idea behind the teak bracket is the upper piece will be the secure point for the bilge strainer which clips to the pump. That upper piece will float atop the main glued piece and fastened by SS hardware (1/4-20 SS threaded insert with 1/4-20 thumb screw), so I can remove the upper piece to remove the entire unit. Also, teak is a decent choice for a wet environment.
That's where I'll put the discharge unless I opt to plumbing like this chap:
https://youtu.be/IiceI0a0PTs?t=410 the caveat to this is a discharge constriction from 1/2" ID of a 3/4" bilge pump discharge to a short section of 3/8" ID for this fitting conversion. This coupled with a check valve will put more back-pressure on the centrifugal bilge pump which will increase amperage a degree. I like the concept, but I don't like how he used a SCH40 check valve and modified the internal spring (just too bulky/heavy IMHO). I've already acquired all lighter fittings and will be starting a proof of concept with my multimeter in series to measure amperage of normal 3/4 discharge vs. this setup.
I'm only running an 8Ah LiFePO4 pack...these are much better than wet cell chemistry because of the DOD (depth of discharge), effectively a 7Ah SLA can only supply 12vdc for about 5Ah whereas a LiFePO4 can for near it's full capacity.
Yes, it's really only for emergency, and with my son at the helm of this one, I'd feel a lot more comfortable in case we get into some nasty weather.