Catalina 34

General Activities => Main Message Board => Topic started by: robbjd on January 07, 2022, 12:06:58 PM

Title: Updating our bilge pump.
Post by: robbjd on January 07, 2022, 12:06:58 PM
We purchased our boat last summer and I've been slowly going through systems and compiling a list of things I'd like to change. Our current bilge pump is a 1750 gpm Jabsco which had a large, and heavy 3 1/4" check valve installed on the discharge. The discharge hose downstream of the check valve was split and leaking so I removed the check and cut back the hose to solve the leak issue. When I removed the pump and float switch for cleaning I found the wiring to be suspect and the pump motor under the "sealed" housing to be badly corroded. I will replace the pump and wiring but would like opinions on a check valve. It seems to me to be a flow restriction with little benefit. Has anyone attempted to replace thier bilge pump hose? If so, do you recall it's length? What pump capacity is typical on 30'+ boats?
Thanks in advance for comments and answers.
More questions to follow
John

S/V Mystic
1997, C34 MKII, Tall rig, Fin keel
Universal M35-AC
Hull #1344
Sarnia, ON, Canada
Title: Re: Updating our bilge pump.
Post by: mark_53 on January 07, 2022, 12:26:21 PM
Since the bilge pump is lower than the discharge, the check valve was probably to prevent backflow into the bilge.
Title: Re: Updating our bilge pump.
Post by: Noah on January 07, 2022, 03:02:18 PM
There is some controversy regarding using a check valve on a bilge pump. I wouldn’t use one. Instead, make a anti-syphoning loop in the hose by bringing/securing a loop of the hose up higher the the waterline.
Title: Re: Updating our bilge pump.
Post by: waughoo on January 07, 2022, 09:06:22 PM
The check valve helps keep the bilge water level low.  Without one, the water in the long bilge hose runs back into the bilge.  Some have said that it presents a restriction in the exit hose that could restrict or block the pump's ability to empty the bilge.  I am currently replacing my pump with a 2000 GPH and a ultra safety system senior float switch with high water alarm.
Title: Re: Updating our bilge pump.
Post by: Jim Hardesty on January 08, 2022, 06:22:14 AM
Quote
Has anyone attempted to replace thier bilge pump hose? If so, do you recall it's length?
Shamrock is also a MKll.  Has a long run from bilge pump to outlet near the stern starboard.  Think that's the reason for your check valve, after the pump stops all the water in the hose will run back into the bilge.  I would not have one. IMHO Any advantage is out weighted by potential down side.  Because the outlet is far above the water line, on MKll, no antisiphon is needed.
Shamrocks bilge pump generally runs twice a year.  Fall to drain the water from water heater, Spring after shaft packing is adjusted fill bilge to clean and check switch and pump.  Other than that it's the turkey baster and sponge.  Bilge stays mostly dry.
Jim
Title: Re: Updating our bilge pump.
Post by: PaulJacobs on January 08, 2022, 07:39:17 AM
I wrestled with this question as well.  The combined engine water & fume exhaust location is indeed well above the STATIC waterline.  However, when powering at full throttle (all diesel engines actually benefit from running at full throttle about 10% of their operating time to minimize the accumulation of blockage in the exhaust elbow), the outflow location is NOT above the DYNAMIC waterline.  Simply stated, at full throttle the stern "squats down" and the exhaust actually goes underwater!
I was concerned that this might draw seawater into the bilge.  So, while Nancy watched the bilge, I ran the engine at 3000 RPM making almost 7 knots, and noted that the exhaust was indeed underwater. I called to Nancy to report on the bilge.  "Nothing coming in" was her response. 
Thus, I concluded - as have others - that a check valve is / was intended to stop "backflow" after the bilge pump has been turned off.  Not worth it IMHO.  Because the C-34 has a keel stepped mast, rainwater will inevitably find its way into the bilge.  Thus, even though in my wildest dreams Pleiades' bilge is bone dry and tidy, in reality she almost always has some water in the bilge.  During the summer, while at anchor when cruising I will occasionally wipe the bilge with a sponge & bucket to get it really clean and dry.  Otherwise, about 1/4" to 1/2" of water in a C-34 bilge is normal.  Even if you DO install a check valve, this will still not eliminate rainwater.

Dr. Paul Jacobs
Pleiades
1990 MK 1.5 # 1068
Tall rig, Full Keel
Yanmar 3YM30 (2014)
Wickford, RI
Title: Re: Updating our bilge pump.
Post by: Analgesic on January 08, 2022, 08:07:42 AM
So, this takes me back to my scariest boating day.   While motoring hard on a windless day in flat calm conditions, I sent my wife down to grab a soda and she screamed "There's water everywhere!"  We switched places and I found water above the floor boards with the bilge pump going full speed.  It took some stressful minutes to realize the hose aft of the check valve under the water heater had vibrated off.  Once I popped it back on the water drained fairly quickly.  Over the next hour (after recovering from my heart attack) I realized the overboard stern exhaust port was in fact below the waterline while motoring hard and my 1988 Mark 1 did not have a loop but a straight downhill aqueduct to the bilge.  A single hose clamp was holding the hose on the check valve.  Lessons learned: double clamp all through hull hoses including in the bilge, loop above the waterline is critical, high volume bilge pump is critical.  Check valve keeps a good amount of water out of the bilge but requires two more double clamping "through hulls."  I replaced a plastic check valve with a bronze one which I think does a great job.  Brian
Title: Re: Updating our bilge pump.
Post by: robbjd on January 08, 2022, 10:17:24 AM
Thanks to all who commented. Pump will be replaced without the check valve, but the float/electronic switch search continues.
These look promising; https://www.bluebgi.com/products/p/bilge-pump-switches/bg-sw, https://www.bilgepumpstore.com/ultra-safety-systems-pump-switch-mini-ups-06-12-v-float-switch-bilge-pump-switch/

John
Title: Re: Updating our bilge pump.
Post by: waughoo on January 08, 2022, 10:27:11 AM
This is what I am installing.  They are a reed switch operated by a magnet in the float.  It is rather simple and is quite bullet proof.  They make a couple different options.  The one I bought has a high water alarm switch built into the float.  They have others that are just a simple float switch for the pump if you choose not to incorporate a high water alarm.

https://www.ultratef-gel.com/product/ultra-bilge-pumpswitch-senior-2432volt/
Title: Re: Updating our bilge pump.
Post by: waughoo on January 08, 2022, 10:29:15 AM
I see now that one of the choices you listed was the ultra safety switch.  Personally, I would recommend that over the electronic set up.  I do think the electronic set up plays a part in a secondary system such as a dry bilge set up, but for my primary system, I wanted aomething a bit lower tech.
Title: Re: Updating our bilge pump.
Post by: Noah on January 08, 2022, 11:31:03 AM
Last bit of advice: make sure you use “smooth bore” hose.
Title: Re: Updating our bilge pump.
Post by: Jon W on January 08, 2022, 01:19:18 PM
You asked what is a typical size bilge pump for our size boat. Generally 1500-2200 gph. Keep in mind a 1500gph pump will most likely not flow the 1500 gph due to head height, type hose, and even your electrical system. I have a 1500 gph, and a 3700 gph bilge pump.

FWIW -
If you don't already have one, add a manual switch so if your float switch fails you can still turn on/off the bilge pump.

Make sure your electrical connections are as high as possible to stay out of any water that may accumulate in the bilge.

Since your replacing your hose, use a smooth bore hose like Trident #147 Bilge and Live Well hose.

Good choice to remove all check valves. They can fail closed, come apart, come away from the hose. My thru hull is high on the transom by the starboard chainplate. Don't know about a MK 1.5 or 2, but on my MK1 I solved the run back problem with an anti siphon valve on a loop under the galley sink. Only run back now is from the few feet from the pump to the loop.
Title: Re: Updating our bilge pump.
Post by: rmjohns on January 09, 2022, 07:16:41 AM
I recently replaced the pump switch in my Mkii. I went with the ultraswitch jr mentioned above. I thing I had issues with between the way the bilge is chambered the volume of the bilge hose, the pump would get into an on-off cycle.

The holes between the bilge chambers don't allow water to flow as quickly as the pump pumps it out so while the pump drained the chamber it was in pretty quickly and stopped, the other 2 or three chambers still had a good bit of water in them. Between that and the volume of water in the pump hose that would drain back in when the pump stopped, it created a non-stop on-off cycle.

I could not find a way to adjust the range of that switch so I ended up moving it to a different bilge chamber.  The chambers take a while to equalize so the pump runs a little longer and gets out quite a bit more water.

It's on my list to add a second smaller bilge pump that gets the water level lower in the bilge. Right now I've moved the refrigerator drain hose to the bilge and use that to vacuum out the bilge.
Title: Re: Updating our bilge pump.
Post by: Ron Hill on January 09, 2022, 03:17:17 PM
rob : I'd get rid of that anti syphon valve.  There are many articles written on why not to have one!! 

I've buried the transom many times, but not so much as to have the electric bilge pump exhaust under water.  You might want to raise your BP exhaust if it is under water when motoring!! I believe that the electric bilge pumps were installed by the dealers (or a previous owner) !!  Only the manual pump can as standard from the factory.

A few thoughts   
Title: Re: Updating our bilge pump.
Post by: Jon W on January 09, 2022, 03:29:49 PM
Get rid of the anti siphon valve or check valve?
Title: Re: Updating our bilge pump.
Post by: robbjd on January 20, 2022, 07:59:23 AM
Spending some quality, albeit cold time on our boat and exploring her systems. Here is a  2nd check valve found a little further down the discharge line. By the time the water passed through the pump,two check valves, and their fittings the pumps 1700 gph potential was probably closer to 500 gph! I have new hose and would love to hear tips or tricks for the daunting task of running new hose.
Title: Re: Updating our bilge pump.
Post by: Admiral_Swellson on January 20, 2022, 08:55:00 AM
I replaced my electric bilge pump hose and it wasn't very difficult. There aren't any places that you can't reach to guide it. Lots of tie-wraps to cut and replace.
Title: Re: Updating our bilge pump.
Post by: robbjd on January 20, 2022, 11:47:05 AM
Robert, do you recall the length of the hose? I have 30 feet.
Title: Re: Updating our bilge pump.
Post by: KWKloeber on January 20, 2022, 12:31:13 PM
I had replaced both my Rule bilge pump and manual bilge pump hoses with Shields 141 PVC Flex Hose (meant for bilge and live wells.)  It's a semi-clear (smoke-gray) smooth-bore, helical hose that seemed very nice to work with.  This year I had to move the manual hose at the bilge end and it's hard as a rock -- in fact to move it out of the way it broke off in my hand.   I tried flexing it a foot farther aft and the same thing - broke off.

Has anyone used that hose nd noticed that issue???  Yeah, its 10 yrs old but still......
I'm wondering if there is a better choice???
My manual hose didn't have a strainer on it and I'd just leave it lay in the bilge - in the past I could flex it 90 deg so the end was flat against the bilge to suck out the last 1/4".  It was quite pliable - like a 90 bend in the distance of 12"-15"  NO way now. 

-Ken
Title: Re: Updating our bilge pump.
Post by: Admiral_Swellson on January 20, 2022, 12:51:55 PM
Robert, do you recall the length of the hose? I have 30 feet.

I don't but it only had to run about half the length of the boat so I probably got 20ft and had some left over.  I used the leftover to create a chaff guard on my most active (windward) dock lines.
Title: Re: Updating our bilge pump.
Post by: robbjd on January 20, 2022, 02:10:42 PM
Thanks Robert. Hopefully you're enjoying some warm weather! Cold here on the Great Lakes! I'll tackle the hose job when it warms up a bit and the hose is more pliable.
Title: Re: Updating our bilge pump.
Post by: waughoo on January 20, 2022, 03:26:01 PM
  This year I had to move the manual hose at the bilge end and it's hard as a rock -- in fact to move it out of the way it broke off in my hand.   I tried flexing it a foot farther aft and the same thing - broke off.

Keenly interested to hear someone's response to this.  The existing white corigated hose in my bilge pump lines is brittle like Ken explains and I was going to replace it with the exact product he mentions, but am now quite leary!! 
Title: Re: Updating our bilge pump.
Post by: Jon W on January 20, 2022, 04:45:12 PM
Hi Ken, I used 1 1/8" and 1 1/2" smooth bore Trident #147 Bilge and Live Well hose for my electric bilge pumps about 5 years ago. Hoses are still good. I did not change the manual bilge hose.
Title: Re: Updating our bilge pump.
Post by: Holger Dieske on January 20, 2022, 10:52:07 PM
Jon: just a question: why do you have 2 pumps? double safety?

Holger
Title: Re: Updating our bilge pump.
Post by: Jon W on January 21, 2022, 11:10:55 AM
Yes. Small price to pay for increased capability that I hope to never need. Primary 1500 gph pump and its level switch are mounted to the bottom of the bilge. Secondary 3700 gph and its level switch are mounted ~ 5" above the bottom of the bilge. Any higher and the top of motor wouldn't fit below the floorboard.
Title: Re: Updating our bilge pump.
Post by: waughoo on January 21, 2022, 07:39:59 PM
I'm curious why you didnt mount the secondary bilge pump also at the bottom and just raise the float switch.  I have been considering a similar setup for my boat as well.  Did you have a reason to set it up that way?
Title: Re: Updating our bilge pump.
Post by: scgunner on January 22, 2022, 09:27:05 AM
Alex,

The small pump is just a scavenger pump to handle day to day needs, the big pump is an emergency pump mounted high designed to kick in and handle whatever gets past the primary. Also I wouldn't want to raise the float switch I'd want to keep it as low as possible so it would start the pump ASAP.

Jon,

That's a great setup, I wish I would have thought of it. Question, do both pumps operate off of the same float switch or does the big pump operate separately when the water level gets higher.
Title: Re: Updating our bilge pump.
Post by: waughoo on January 22, 2022, 09:57:21 AM
There are definitely two float switches in there.
Title: Re: Updating our bilge pump.
Post by: Jon W on January 22, 2022, 10:41:48 AM
Alex, the secondary pump is mounted higher in the bilge for the reason Kevin described. Additionally the 1 1/2" discharge hose is pretty stiff for that tight area.

Kevin, each pump has its own level switch, breaker, and thru hull. The breakers are located on the main distribution panel.
Title: Re: Updating our bilge pump.
Post by: scgunner on January 22, 2022, 11:15:19 AM
Jon,

Very well thought out. Let's hope you'll never know how well it works!
Title: Re: Updating our bilge pump.
Post by: Ron Hill on January 23, 2022, 02:24:26 PM
Guys : Years ago when I replaced my bilge pump hose I let the old hose lay in the bottom of the bilge and ran the other end of it to - under the head sink. 

I have an adapter attached, so that in a real bilge pump needed emergency I can connect it to the raw water engine Hose and have the engine pump water from the bilge!!  You could also just run a piece of 5/8" hose from the bilge to the area under the head sink!!  Just another back up idea!!   :thumb:

A thought !!