I should have titled the thread 'lack of' limber holes. The bilge in my C36 has very, very small 'slits' going through the floors above the keel. This only allows a very small flow of water from one 'compartment' to the next. If I run the bilge pump, it'll empty the compartment it's in pretty quick, then it takes about 5 minutes for water to drain from the adjacent compartment to the pump, get emptied, etc., etc., etc. So if there's 4" of water in the bilge, it takes quite a few cycles to get it out. I can't for the life of me figure out why it was done that way in the factory.
I've decided it's time to attack the problem. I planned to cut an approx. 1 1/4" hole through each floor and run a piece of PVC or other plastic pipe through it, sealing around the pipe to make it water tight. Thing is, I don't know what's inside the floors. Are they hollow, or is there wood encapsulated in fiberglass.?? I've never looked in another C36's bilge, but seem to recall seeing pictures where it looks like there's a substantial 1 or larger pipe going through each floor. I'm fairly certain their is encapsulated wood that the keep bolts through, at least there was on my C30.
Any advice? Anyone else have this issue?
PS. meant to take pics on launch day but forgot.
Gary and Cathy Price
1997 C36 Mk II Tall Rig/Wing Keel Imagine...
Hull # 1617
Worton Creek, Md.
Northern Chesapeake Bay
Gary,
I believe you are correct about the construction being glassed over wood frames in the bilge supporting the floor and stiffening the hull. My frames ( an 1988 MkI) has fairly substantial gaps at the base of the frames, that stated it still takes a while for water to make its way to the bilge pump section, I contribute this more to the flat nature of the bilge area. I always need to use a sponge to dry all four chambers of the main bilge, not for lack of limber holes but due to the flat section in this area.
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
What I find confusing is do you mean floors or dividers within the bilge? The dividers form seperate compartments in my bilge Bow to Aft. If you are referring to the dividers they may be wood or some composite material "glassed over" My bilge has limber holes about 1" made from what looks like plastic pipe. It does sound like you need to drill a hole at the bottom of each divider and glass in a pipe as you stated. I'm surprised your did/does not have.
Gary Bain
S/V "Gone With The Wind"
Catalina 36', Hull #: 1056, Year: 1990, Engine: M-35
Standard Rig
Moored: Boothbay Harbor, Maine
Home: Auburn, Maine
Technically, those 'dividers' are called floors in boat construction terms; I couldn't think of a clear way to describe them, so that's the term I used. I found this definition -
Floor or Floor Timber - A transverse structural member lying across the keel and tying the frames on either side of the keel together. Floor timbers join both sides of a vessel together and make up the substructure for external keel fastenings, engine beds, and mast steps.
Boats seem to have a number of terms that mean something else in a house. Like the 'floor' in a house is a 'sole' in your cabin and the 'ceiling' in a boat is that wooden trim on the cabin sides; what's above your head is the 'overhead'. At least you know where to look for that one :rolleyes:
Wasn't trying to be a wise guy, just using the best terms I know to describe them. Dividers gets the point across too.
Gary and Cathy Price
1997 C36 Mk II Tall Rig/Wing Keel Imagine...
Hull # 1617
Worton Creek, Md.
Northern Chesapeake Bay
Got it, as I said that term was confusing me so I wanted to make sure it was the same thing. Makes sense as "floor support".
Gary Bain
S/V "Gone With The Wind"
Catalina 36', Hull #: 1056, Year: 1990, Engine: M-35
Standard Rig
Moored: Boothbay Harbor, Maine
Home: Auburn, Maine
Hmm, I would have called 'em stringers.
Mine, too, have a small hole about the diameter of my little finger. Water drains through from one to another very slowly. However, I have recently gone to a two-pump system as described on this site by Tom Soko, and the 'nuisance' bilge pump I installed is only 360gph, so the draining of the water from compartment to compartment just about keeps up with the bilge pumping.
I highly recommend using two pumps, one of them small-bore with an anti-siphon loop under the sink. Keeps the amount of water in the bilge very low, and if it has to cycle on twice because of slow flow between compartments, I'd be happier than weakening my stringers/floors/floor supports with 1 1/12 " holes . . .
imho :)
- nick
Nick Tonkin
*Former* Website Administrator, C36/375IA
*Former* owner, C36 tr/fk #255, Santa Barbara, CA
Nick - do you have a picture of your bilge set up? I often have more water than I want and have contemplated adding a second smaller pump. However, I am not to keen on drilling another hole in the transom for the water to exit. Do you have it looped into the main bilge line by any chance? Dumb questions...though this project seems easy enough but also seems like it could be a huge pain....Any guidance is greatly appreciated! Thanks.
Jack Bahen
Kinera - 1985 C36 Mk I Tall Rig
Hull # 422
Annapolis, MD
Jack,
EVERYTHING I have read says that you should not combine one bilge pump hose into another. You should have two distinct switches, wiring, fuses, pumps, and hoses. Your boat, your choice.
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
Jack,
There's nothing wrong with drilling another hole in your transom. Use a hole saw of the right dimension (measure the threads on the fitting). Use a fat bead of 4200 adhesive on the outside half of the fitting only. Leave it about 1/4" from the outer edge of the flange as it will squish out when you tighten it. Hand tighten, then leave overnight so the 4200 mostly cures, then tighten fully.
As Tom points out it would be a bad idea to combine two bilge pump discharges into one hose because (1) the hose would not have the capacity for a serious flood when both pumps were working, and (2) depending on the installation, the discharge from one pump could return to the bilge via the other hose.
Tom is quick to provide links to technical articles on our site; he must be too modest to highlight his own excellent article on this project. I'll do it for him: [URL="http://www.c36ia.com/node/944"]Tom's bilge pump installation[/URL]
I found it better to place the nuisance pump's float switch in the same (aftmost) bilge compartment; I don't find a problem with the pump cycling as it doesn't turn on until the float switch rises higher than it does on the tiny amount of backwash. I also placed the larger pump in the same compartment (with its float switch in the next one forward), because the existing 1 1/8" hose enters there and it was going to be really hard to drill a new hole between the bilge and the compartment outboard of it.
Finally, I also suggest you check carefully what you now have before proceeding. My boat had a single 1100 gph pump with a 1 1/8" discharge hose. The pump wasn't high enough capacity for a main pump, and the original through-hull fitting was for 3/4" hose so it was constricted anyway through an ugly series of reducers! I wound up running the new, 350 gph nuisance pump to the old through-hull fitting and drilling a new hole for a 1 1/8" fitting for the big pump.
Hope this helps!
- nick
Nick Tonkin
*Former* Website Administrator, C36/375IA
*Former* owner, C36 tr/fk #255, Santa Barbara, CA