Looking for some advice/experience.
When I purchased my C36 one of the problems noted by the surveyor was that the water pump "pulsed" rapidly (several times per second causing the amp meter needle to spike on every pulse). The pump was a sure-flo 2.8 gpm pump. I have replaced that pump with a sure-flo 3.8 (not new, but working) and it exhibited the same problem. After doing a little research I adjusted the pressure switch to the point where the pump now comes on approx. every 2 seconds. This is better, but doesn't seem optimal. Previous boats on which I had experience, the pump would run continuously if a tap were turned on. So, this is a new behavior for me. I could not adjust it so that it runs continuously.
I know there is a very slow leak at a water heater fitting. With no taps on, the pump will come on for about half a second every 5 minutes or so. In my limited experience it doesn't seem like that slow a leak would contribute to the other problem. Actually, if I am thinking right, the problem is opposite. That is, it's building enough pressure while a tap is open to turn itself off, then back on as pressure drops.
Suggestions?
Thanks,
Jeff
S/V Wind Ensemble
1987 C-36 Wing Keel
Universal M25XP 23hp
Hull #705
Coastal Alabama
I've always had an accumulator like this one in both my C30 and current C36. [url]http://www.westmarine.com/webapp/wcs/stores/servlet/ProductDisplay?produ...
It stops fast cycling pretty well. I've read of people making them from 4" plastic pipe with some rubber balls in it and the appropriate fittings to plumb it into the water system; probably cheaper. I believe the commercial models have a bladder of some sort in them.
Before installing the accumulator, I could get my pump to 'stutter' on and off by cracking a faucet just the right amount. With it, the pump probably cycles on about every 10 seconds when someone is in the shower.
Gary and Cathy Price
1997 C36 Mk II Tall Rig/Wing Keel Imagine...
Hull # 1617
Worton Creek, Md.
Northern Chesapeake Bay
I just replaced my fresh water pump last week with another Extreme Smart Sensor 5.7 Water Pump. Shurelo has a " no questions asked 3 year warranty". Just had to pack it up, include a copy of the original receipt and sent it back. I discovered there is an adjustment screw on the end of the pump that helps to prevent the pump recycling too often. I would recommend it for a quiet operation.
Glenn Druhot
Carpe Diem
New Bern, NC
35* 6' 10" N / 77* 2' 30" W
2001 C36, Hull #1965
Std Rig; Wing Keel; M35B
Sounds like the accumulator is the way to go. Regarding the adjustment screw on the pressure switch, all the way in, it cycles very fast. With the screw all the way out, it cycles about every 2 seconds.
Thanks,
Jeff
S/V Wind Ensemble
1987 C-36 Wing Keel
Universal M25XP 23hp
Hull #705
Coastal Alabama
I did the accumulator tank last year and it really helped the short cycling of the pump. I would highly recommend. I used the smaller 1 liter tank but would go to a 1 gal model if I had to do it again.
_____________
Harold Baker
S/V Lucky Duck
Duncan Bay Boat Club
Cheboygan Michigan - Lake Huron
1989 C-36 mkI TR/WK M25XP
Find and fix all your leaks. The pump is trying to maintain pressure in the lines, it doesn't take much of a leak to cause a loss of pressure. The loss of pressure causing the pump to come on. I keep my pump switch on when I'm on the boat. The pump only actuates when a fawcet is turned on.
Some of the clamps are hard to find, make sure you tighten every one.
Ken and Vicki Juul
SV Luna Loca
C34 #1090
Chesapeake Bay
When any of our faucets are on, the pump runs continuously. It will unless it has an accumulator or is one of the newer style pumps. I don't understand the mention of "cycling" unless you are simply slowly opening a faucet or only opening it a tiny bit.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)
I agree with Ken. You have a leak somewhere causing the pump to cycle on and off. Remember to include checking the stern shower plastic water fittings. I have had slight leaks there in the past. Be careful not to overtighten those fittings as they can crack.
By the way, I just installed a new ShuFlo 3.0 on my boat. I leave the panel switch "on" when on the boat and have zero cycling. The pump does run continuously when the faucet is open.
Stephen Kruse
Kruse Control #1428
1995 C-36 MKII SR/WK
Lake Lanier, Ga.
If there is a leak and I would think there is, you should be accumulating some fresh water in the bilge. Certainly it would be the first place to check. The pump should cycle on only when used and not pulse. I agree that some of the connectors are in odd and sometimes difficult locations, but it is well worth tracing all the lines and tightening all of the clamps before shelling out for a new pump only to find you have the same problem.
John Meyer
Hilbre 2135
San Pedro, CA
John Meyer
Hilbre
C36 MKll, Hull 2135
Cabrillo Marina, San Pedro, CA
Jeff
This might not be your exact problem, but is there a water filter in the system?
Not proud of it, but I once tossed an otherwise perfectly good pump in the dumpster only to find that the new one did the same thing - ran nearly continuously with an open tap, without building any pressure. Culprit turned out to be a canister-style water filter under the galley sink. Changed the filter cartridge and all was well, except for my pride and barked knuckles thanks to Butler & Co's locating the pump in an unhandy spot.
Hustled back to the dumpster to do some "diving," but no joy - it was empty.
Have to concur with other responders that there can be no leaks in the freshwater system and adding an accumulator is a good idea - not that mine has one.
Good luck.
Jack
Often wrong, but never in doubt
Jack Heaston
1987 C36 Mk I #692
Fin Keel, Std Rig, Rocna 15
Silent Passage, M25 XPB Repower
PULSING
I think I now understand what you mean.
When you only turn the furthest tap from the pump, like the head faucet, on ONLY A VERY LITTLE BIT, the pump will "pulse" - when you open the faucet a tad more, the pump continues to run.
The issue, then, seems to be how much you open the faucet, in addition to your known leak.
I, too, don't like that pulse sound, but it is NOT an indication anything is wrong with the pump: it's doing it's job to keep the pressure up, but it can "come and go" simply because you're only letting a very little pressure go with a partially opened faucet. Sure, it may save water, but if you're concerned with that AND the pump noise, get an accumulator or a newer style pump as previously discussed, or one of those Scanvick water wands. I have one we use on long trips, really works.
Stu Jackson, C34IA Secretary, C34 #224, 1986, SR/FK, M25 engine, Rocna 10 (22#)