Where should my bilge pump drain to?

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ahfdoc
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Where should my bilge pump drain to?

Hoping for your advice.
Currently I have a manual bilge pump which drains to a thru hull at the center of the transom. There is also an electric bilge pump that empties through the same thru hull as the sink in the head (T fitting).  This thru hull is under the water line.  The pump is small and does not have a float switch.  When the switch is off (majority of the time) it of course is not working.  This doesn't seem ideal to me.  I have decided to put in a high quality properly wired electric bilge pump with a float switch.  The question is where it should empty? The options I am thinking of:
1. T it to the thru hull on the transom that the manual pump uses?  I have read here that is not a great idea?
2.  Pipe it back to the transom and put in a new thru hull there?
3.  Put a new thru hull on the hull near where the pump is?

Advice?

Mike and Sarah Dickinson
Mes Trois Filles
Holland, MI
C36 / 1984 / Hull 0219

dpower
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I am unfamiliar with the setup on your year boat. On the MKII, the main bilge pump and the manual pump operate out of the bilge in the main salon, together with the float switch. The auto/manual switch is on the electrical panel. There is also a shower bilge pump in the head floor that, when activated, drains through the head sink thru hull.

David S. Power
Two If By Sea #1687
Burnt Store Marina
Punta Gorda, FL

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Parsons
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+1 to dpowers comment, but I’m also on a Mk II. Our auto pump design goes through a T, and shares the same through hull as the manual pump. Not a great design, but not worth me adding another through hull as I’m not crossing oceans.

Are you sure that the pump you’re talking about is not the shower sump pump?  There is a seacock between the pump and through hull, and it is below the waterline, so that’s two terrible designs. There should be nothing between pump and overboard but good quality, smooth interior hose.  If I was in your situation, I’d pick option 2, and install a 2000 gph pump with a good quality external float switch in a separate bilge compartment so the pump doesn’t agitate the float when operating.  BTW, the Ultra Safety System switch is widely regarded as the best made, but costs about $150.

John Parsons
"Water Music" 1999 Catalina 36 Mk II - Hull 1771
Tall Rig, Fin Keel
Bay City, MI, USA

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ahfdoc
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Thanks so much for the feedback!
I should have mentioned - it also has a shower bilge pump.  I am not sure where that empties. I am a little concerned that it dumps into the bilge in the main salon.
I am suspecting that this early MK1 came with just the manual bilge and the shower bilge and that someone later added an electric bilge pump and connected it to the outflow from the shower bilge?

One more question:  On your MK2, does this mean you have two hoses from the main salon bilge to the transom? (One through the manual bilge pump and the other to a T at the transom thru hull?)

Thanks again for the advice.  I have a highly rated 2000 gph with a good float switch, Auto/Manual switch to add to the electrical panel, and an alarm to let me know when it trips on automatically, etc...  (Helpful ideas from Tom Soko and others on this site already...)

Mike and Sarah Dickinson
Mes Trois Filles
Holland, MI
C36 / 1984 / Hull 0219

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Chachere
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Take a look at Tom Soko's write-up of how he plumbed the second pump in his C36 here: www.catalina36.org/members/technical/upgrades/adding-second-bilge-pump and a discussion of why plumbing it to the sink drain is a pretty bad idea, here: www.catalina36.org/forum/technical-discussion/bilge-pump-sink-drain
We followed Tom's system on our boat.

[quote=ahfdoc] ...
I should have mentioned - it also has a shower bilge pump.  I am not sure where that empties. I am a little concerned that it dumps into the bilge in the main salon....
[/quote]
On our boat -- and I believe others of that vintage, -- the shower bilge pump goes to its own seacock under the bench seat in the head (next to the head intake seacock), after first traveling up behind the cabinets to a siphon break loop.  
Looking at the sketch of the plumbing system in the MkI owner's manual, however, it looks like Catalina at one point had the shower sump drain sharing the seacock with the head sink drain, and the head intake its one seacock. See www.catalina36.org/sites/default/files/legacy/C36MkI_Owners_Manual.pdf  at PDF page 32.

[quote=ahfdoc] ...
Does this mean you have two hoses from the main salon bilge to the transom? ...
...[/quote]
It could be  -- from looking at the manual (See www.catalina36.org/sites/default/files/legacy/C36MkI_Owners_Manual.pdf  at PDF page 33-34)  that the early models only had the manual pump (and thus one hose)   But in any event, we now have three hoses to the transom from the bilge: one for the manual pump and one for each of the electric bilge pumps (we added a small through hull for the second electric pump).   Its not a hard job to snake a hose up under the floor to the transom area.
We've never had occasion to use the manual pump (although its nice to know its there),  but several times on of the electric pumps has crapped out without warning, and it was good to have the second one take over automatically.

Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY

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Parsons
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[quote=ahfdoc]

One more question:  On your MK2, does this mean you have two hoses from the main salon bilge to the transom? (One through the manual bilge pump and the other to a T at the transom ...

Yes, I have two hoses, one outlet from the auto pump, and one inlet to the manual pump in the transom. Both go to a single through hull with a T connection.

John Parsons
"Water Music" 1999 Catalina 36 Mk II - Hull 1771
Tall Rig, Fin Keel
Bay City, MI, USA

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ahfdoc
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Just some final feedback.
I decided to just "do it right."  I followed the plans and suggestions from this site (Tom Soko and others).  I pulled a large drain tube and a small drain tube to the transom. I added two new above the water line thru hulls.  In the main salon bilge I now have:  A large high capacity bilge pump in one portion, the float switch for this in another portion of the bilge, and a small capacity bilge pump in the third (to empty out the "nuisance" residual).  It was not as hard as I thought to get to all the compartments that I needed to in order to pull the tubing to the transom.  I am unlikely to need all of this but nice to know that if something inadvertantly breaks, at least I have some protection.  Happy to not have my bilge pump emptying through the lavatory sink.  Also nice to know that it is set up the way that I think it ought to be.

Mike and Sarah Dickinson
Mes Trois Filles
Holland, MI
C36 / 1984 / Hull 0219

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ahfdoc
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So my work on this upgrade paid off last night. Was getting ready to leave the boat for the night when the bilge pump kicked on. I went to check and my bilge was really really full of water. Fortunately my high capacity bilge pump was able to pump it out while I searched for the problem. As I went thru hull to thru hull I eventually found the problem. The air conditioner takes water from below the water line. The return line had slipped off and was like a wide open garden hose pouring water into the boat. I have since fixed it (and added the second hose clamp that should have been on the connections). Nonetheless I am am very happy that I had a good high capacity system that I can leave in “auto” mode when I leave. It could have been a catastrophe...

Mike and Sarah Dickinson
Mes Trois Filles
Holland, MI
C36 / 1984 / Hull 0219

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Chachere
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Also a good demonstration in support of the proposition of closing EACH and EVERY seacock when one leaves the boat for any length of time...
 

Matthew Chachère
s/v ¡Que Chévere!
(Formerly 1985 C36 MKI #466 tall rig fin keel M25)
2006 Catalina Morgan 440 #30.
Homeported in eastern Long Island, NY

TippingPoint
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Posts: 46

I have a 1984 Catalina 36 and found the hose going to the T-connector Manual Pump rotted, severly compromised, it turned out I was pumping water back into the bildge.   I removed hose out and installed a thrue-hull on the port side below just below the toerail, 3\4 white hardly noticable.  It is only a 6' run to the outlet.    I repurposed the transome thru-hull for the propane locker vent.

Not to be a buzzkill but the bildgepump will not stop your boat from sinking, I think the intention is to keep your bildge relatively "dryish".

Ed 
 

Ed Dewsnap
Marion, MA
1984 Catalina

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