bilge pumps/switches/battery drain

[sastanley]

Maybe electrical is the best place, just need a new thread.

this is a quote from page 3 in the ACR thread, but someone thought maybe we should start a new thread to avoid contaminating the fascinating (yet over my head) ACR/charging discussion.

This is my comment from that thread (post #49) that sparked some interest. After you catch up, come back here and comment.

Steve,
My step-father worked for VW for a while. They used to put small solar panels (with suction cups) on the dashboard/windshield when the cars were delivered to the states. They found a way to make the solar panels cheap enough that it was more economical than replacing the battery after they sat in the lot for days/weeks on end to be sold/transported/ etc..so parasitic drain is a reality. This was VW's solution. These panels were pretty small, maybe 14" x 10"..but were rigid, and plugged into the cigarette lighter since that was wired to be hot all the time.

A small flexible panel (10watts maybe?) is likely enough to keep ahead, and probably just enough to keep the battery topped off. You guys can do all the math, but it seems that they produce something like 2-3 amps. I have no shore power on my Catalina, and I am considering this for my boat. I am cheap though, and I'll likely just put alligator clips on the end and swap it to the other battery on each visit. I also have no electronics that would produce parasitic drain, but I am considering a bilge pump w/ float switch.

I think my plan is to simply add a switch in the bilge to make the pump run if things leak. I try to visit the boat every two weeks when it is in the water, so I can't see things going bad unless there is a failure. I am also replacing the remaning two original pipe nipples with real thru-hulls, so I hope I don't have to worry about any leaks anyway. New hoses & double clamps everywhere should take care of that. The stuffing box drips about once every 15 seconds.

OK...have at it! (p.s.> Hope this is OK with the board Admins & Mr. Moyer! - they can certainly delete if they feel it is necessary.)

[s/v Dearbhail]

Shawn
When I bought our boat there was a 500 gph bilge pump that had to be turned on manually, and a manual back up. I upgraded that to a Rule 750 gph with a built in float switch. I would have went larger but that was as big a pump as I could fit in the hole. I was feeling pretty good about that since the boat is normally dry. At least it was until last May.

We were caught in some weather and decided to drop the sails and run for port on the A4. I was running her pretty hard at the time beating against the tide and wind. The engine had been running about an hour when my sailing buddy happened to look into the cabin and noticed there was about 4 inches of water sloshing around my normally dry boat. Corrosion on the inside of the side plate let go and we were pumping water into the boat and some out the exhaust. We reduced rpm and watched the engine temp closely until we reached port. I knocked the water level down using the Rule 750 and the manual pump, a Whale guzzler.

The Rule 750 was running but did not stay up with the water being pumped in by the A4's water pump. Because of that I installed a second, larger pump, a Rule 1500 gph. I have no idea what others are running as far as capacity but that's what we have in our Northwind 29.

Mark
s/v Dearbhail

[Mark S]

Mark,

That's everybody's nightmare. Are you speaking of the side plate by the "T" fitting on the block adjacent to the starter and alternator?

Mark S

[sastanley]

Wow...thanks for the story. I am sure the currently installed pump would not keep up.

With a 30 yr old engine you never know when something like the sideplate (or the Marine Tex'ed drain tube from the block which I've found in my boat) might fail.

[s/v Dearbhail]

Mark S.-

Yes it was the side plate with the t-fitting. Two large holes, 1/4 and almost 1/2 inch let go. There were also several smaller holes visable after I had the plate off and tried cleaning it up. The plate had to be replaced.

There was water spraying in on the alternator and the starting battery not far away.


Shawn-

In rebuilding the boat I always try to add simplicity to the design, and if possible a back up, maybe even two back ups. For example, with the bilge pumps, I upgraded my capacity, went to a second even higher capacity pump and kept the manual back up. Power for each bilge pump comes from the house battery, but the starting battery has a normally off switch to operate the pumps if something goes wrong.

Mark on s/v Dearbhail

[sastanley]

Mark,
Maybe I will return my uninstalled 800GPH pump and pony up a few more $$ for a higher capacity.

I have a manual pump on the boat too, but it is the grey portable variety that I do not think would be fun to operate when you are standing in ankle deep water.

I think my battery terminals are probably 15" above the bilge on the carb side of the motor...so they shouldn't short out until we've decided to abandon ship, but it is something to consider. You bring up many interesting points with water intrusion. Today I whacked out the original glassed in pipe nipples from my Catalina 30 and hope to get to the boat this weekend to install real thru-hulls and seacocks.

[s/v Dearbhail]

Mark,
Maybe I will return my uninstalled 800GPH pump and pony up a few more $$ for a higher capacity.

I have a manual pump on the boat too, but it is the grey portable variety that I do not think would be fun to operate when you are standing in ankle deep water.

I think my battery terminals are probably 15" above the bilge on the carb side of the motor...so they shouldn't short out until we've decided to abandon ship, but it is something to consider. You bring up many interesting points with water intrusion. Today I whacked out the original glassed in pipe nipples from my Catalina 30 and hope to get to the boat this weekend to install real thru-hulls and seacocks.

Your 800 is probably fine for most dewatering jobs.

You bring up a good point about the battery terminals; however I was more concerned about the engine ingsting water. The flame arrester on my A4 is abou7, maybe 8 inches above the hull (bottom of bilge). With 4 inches of water sloshing around in a rough sea state,,,

Sea cocks are on my list. Mine are old and do not have grease or drain ports. I operate them all regularly but can't really maintain them. Next haul out.

[sastanley]

Mark,
My battery terminals are definitely higher than my flame arrestor...I never thought about that!

There are some new seacock fittings that have a port on the top of the seacock that allow you to close the seacock and then 'pull the plug' to suck water from inside the boat using the engine's raw water pump...I guess this assumes the engine intake seacock isn't the water ingress culprit in the first place.

This is a similar item, but an add-on from Groco..there are some companies that have this integrated into the seacock I think.

http://www.jamestowndistributors.com/userportal/show_product.do?pid=14693&familyName=Groco+Safety+Seacock+Conversion+

[sastanley]

Some of the stories in here just reminded me about a powerboat buddy a few years back that was having some trouble and wasn't sure what the deal was, so, he asked me to come by and help him diagnose his engine trouble. The boat was on a trailer in the driveway after he'd had it out with the family over the weekend.

edit (oops, I didn't realize I deleted the prognosis) - It turns out he blew a freeze plug..

We hooked up the muffs, fired her up and stuck our nose down in the engine room and water was spraying everywhere.
me to buddy- "D, did you have any water in the boat when you were out?"
buddy to me- "you know Shawn, I didn't really notice any water but there was lots of steam when we had the engine on. And, the bilge pump did run the whole time!"

[msmith10]

I have an 800 gph pump with automatic switch for my "normal" bilge pump. This has about a 3/4" outflow tubing. It also has a manual override switch. Higher up in the bilge, I have a 2000 gph pump which has only a manual switch. That is my first emergency pump. It has about a 1-1/2" outflow tubing. I then have a manual Whale pump. To minimize thruhulls, I connected the Whale pump tubing and the big pump tubing with a Y adapter just inside the thru hull, and put a check valve on the manual pump hose side. This setup gives me a lot of pumping capacity. Yes, there's a sacrifice putting the two hoses on a Y, and having a check valve in the one hose, but if you're in that much trouble, you're in deep. Also, you're not going to be pumping that manual pump for very long-- try it some time. You don't want too large a pump for your normal pump. The output hose is so large the water will just drain back into the bilge when the pump shuts off and the pump will be cycling all the time just to move that water around, not to mention the battery drain from a big pump. I do believe everyone should have a backup powered bilge pump-- at least the ability to pull your engine water intake hose off the intake thru hull and put the hose into the bilge to allow the engine to act as an emergency pump.

[s/v Dearbhail]

Boat US article

The link is for an article, "Why boats sink" from the Boat US magazine-

http://www.boatus.com/seaworthy/sinking/default.asp

[Administrator]

Somewhere on the Internet, there's a table which shows how much water flows through holes of various diameters at various depths below the waterline. It's frightening. Then again, anyone who's swapped out a knotmeter sending unit for the dummy plug has some appreciation of the physics.

Wish I could find that...

Bill

[alberg]

Volts x amps=watts so to get 2-3amps you need 12.5v x 3amps = 37.5 watts don't forget to derate by 50% because you don't get full energy all day. So to get 3amps you will need a 70 watt panel.A 10watt panel will give on average 0.4 amps enough to keep a small battery topped off.

Alberg

[sastanley]

alberg, thanks for your input...I was too lazy to do the math.

Bill, you are right..when I go racing with my step-father, we alternate who gets to clean the knot-meter thru-hull (each week one of gets a beer and the tiller, and one of us gets the plug & the cleaning task as we motor out!)...even swapping with the plug in your hand results in a couple of gallons of water in a few seconds. It seems that a 800GPH pump that may be able to physically remove that much water is likely limited by its discharge (hose) diameter. Again, in a catastrophic failure situation when the owner is at work, or away from the boat, , how long do you expect the battery to run that pump??

[Administrator]

Well, I didn't find a table, but I did find a data point. A one-inch hole two feet below the water line allows 1,680 gallons per hour into the boat. Those parameters are roughly equivalent to a seacock or knotmeter sending unit failing, I would guess.

An Edson diaphragm pump with 1.5 inch ports is rated at 1,080 gallons per hour at 46 cycles per minute. Think about that for a minute....

Bill