Bilge Pump Problem

[RonRelyea]

I've got a Rule bilge pump (I think its a 2000) ... there are times when the float switch will be triggered, and the motor will run but the pump doesn't move any water. If I jiggle the float switch off and on a couple of times it will eventually kick in and operate correctly.

I have some kind of brass connector in-line on the output .. possibly a back flow preventer??

Is it time to replace the pump, or is there something I can do to correct the situation??

 

[Deleted member 78819]

If the pump motor is running but she isn't pumping water when she should the impeller may be shot... else, maybe the float is mounted lower than the pump? Don't know if that can be done but if so, maybe the float kicks in the pump but the pump isn't in the water?

 

[RonRelyea]

re: Bilge Pump

If the pump motor is running but she isn't pumping water when she should the impeller may be shot... else, maybe the float is mounted lower than the pump? Don't know if that can be done but if so, maybe the float kicks in the pump but the pump isn't in the water?

Thanks Steve ... the float is OK ... and there is water in the bilge enough to trip the float ... I was first thinking it could be some kind of air lock problem since jiggling the switch on and off in rapid succession will eventually get the pump working fine. It sometimes works just perfectly by itself without intervention - so it is an intermittent problem ...

Does anyone know if the impellers on Rules are replaceable?? If so, I'll pull the pump and see if there might be a defective impeller.

 

[Barnacle Bill]

Usually the impellers are plastic and not rubber. The in line device might be a check valve which prevents water in the hose from falling back into the bilge.

 

[MLampner]

Other Possible Issues

If your unit has a strainer, check to see if it is partially clogged, I have had a similar problem why the turning on and off works to clear it it only clears it by pushing the problem away. That happens when the pump turns off and some water falls back through it pushing any blockage temporarily out of the way.

I always try and keep te bilge squeeky clean to minimize that problem but since the shower drains to it hair etc can get in and begin to clog things up. I've thought of putting a shower sump in but since we only use the shower once or twice a season doesn't seem worth it.

The second possible problem is the pump wiring may be failing, since it is easy to get the connections wet and corrosion is a real issue it can slow the pump way down. If that is the case giggling the float may also be moving the wires just enough that a better contact is made and the pump runs better. I would bet on the first the second is a long shot.

 

[Don Crowther]

Have you pulled the pump yet? You might have something blocking the intake or exshaust. By turning the pump on ond off via the float switch the little water that's moved when the pump is on back flows when the pump shuts off. Then when you turn the pump back on the blockage has been moved and the pump runs as it should

 

[Benny17441]

Make sure the strainer is clean and there are no obstructions. Don't know what that brass connector may be but the use of valve to prevent backflow to the bilge pump is not recommended. If the strainer si clean an intemittent problem is likely electrical so check wiring and connectors and if all check out it may be time to replace the pump. They only seem to last for about 5 years.

 

[John T1594]

Airlock or head pressure

If you want to keep the check valve on your output hose, make sure that there is only a short piece of hose between the pump and the valve. That reduces the air in the line before the valve and seems to allow the pump to open the valve easier. At least it works on my boat.
Alos, make sure that your pump is firmly clamped to the bottom of the bilge so it does not draw air and cavitate.

 

[tkanzler]

If you want to keep the check valve on your output hose, make sure that there is only a short piece of hose between the pump and the valve. That reduces the air in the line before the valve and seems to allow the pump to open the valve easier. At least it works on my boat.
Alos, make sure that your pump is firmly clamped to the bottom of the bilge so it does not draw air and cavitate.

This is almost certainly what's happening, and what you should do about it. My Hunter 340 had a very narrow but deep bilge, and the backflow from the discharge hose would raise the level enough to trigger the pump so it would cycle endlessly. The previous owner had installed a check valve, which stopped that from happening. I fully understand why.

Nobody makes an extended range float switch, which is what would be needed for my bilge. That, or a smaller pump and/or smaller diameter discharge hose.

In addition to what the previous poster said above, also consider raising the float switch so that the pump stops before it draws air. If it stays flooded, it will probably have no trouble restarting. You can test that by intenionally flooding the bilge, get the pump to run (and pump steady), then shut it off. Wait, then restart. If it's a matter of getting air in it, made infinitely worse by the check valve, then it should start pumping instantly when it restarts, as long as you stopped it before it drew any air.

Another thing you can do is drill a small hole in the discharge hose, just before the check valve, so the air can vent enough to flood the impeller completely when it starts. It's obviously best to not even have a check valve, but some boats can be a real challenge without one. Perhaps you should take the check valve out and see how high the backflow gets without it.

Oh, and you could always use a smaller diameter hose if the backflow causes short-cycling, but that's going to restrict the flow rate.

Pick your poison.

Edit: Doh! Just noticed the previous poster also has an H340, so I'm sure he knows exactly what I'm talking about.

 

[RonRelyea]

Bilge Pump Problem - follow up

Thanks to all for the suggestions ...

I'm leaning towards it being a cavitation or an air lock. The electric is fine, pump is attached to bottom of the bilge, when it does kick in, it works fine, so I don't think it is the impeller. The strainer is not blocked.

Could it be air in the pump? This is the scenario when it happened last ... 1) bilge was bone dry . 2) lost dock power and my refrigerator dumped water into the bilge. 3) water was not high enough to trip the pump on 4) I manually lifted the float switch to clear out the bilge. 5) motor turns on but no pumping occurs 6) raise and drop float switch a number of times to turn pump off-on-off-on-off-on and finally it starts sucking.

In writing this out, I now start to wonder what would happen if I added water to the bilge to the point where the float switch kicked in by itself with no manual intervention. Maybe a higher water level would force air out of the pump ???? I've got to test this out.

 

[RonRelyea]

Probably it!!!

This is almost certainly what's happening, and what you should do about it. My Hunter 340 had a very narrow but deep bilge, and the backflow from the discharge hose would raise the level enough to trigger the pump so it would cycle endlessly. The previous owner had installed a check valve, which stopped that from happening. I fully understand why.

Nobody makes an extended range float switch, which is what would be needed for my bilge. That, or a smaller pump and/or smaller diameter discharge hose.

In addition to what the previous poster said above, also consider raising the float switch so that the pump stops before it draws air. If it stays flooded, it will probably have no trouble restarting. You can test that by intenionally flooding the bilge, get the pump to run (and pump steady), then shut it off. Wait, then restart. If it's a matter of getting air in it, made infinitely worse by the check valve, then it should start pumping instantly when it restarts, as long as you stopped it before it drew any air.

Another thing you can do is drill a small hole in the discharge hose, just before the check valve, so the air can vent enough to flood the impeller completely when it starts. It's obviously best to not even have a check valve, but some boats can be a real challenge without one. Perhaps you should take the check valve out and see how high the backflow gets without it.

Oh, and you could always use a smaller diameter hose if the backflow causes short-cycling, but that's going to restrict the flow rate.

Pick your poison.

Edit: Doh! Just noticed the previous poster also has an H340, so I'm sure he knows exactly what I'm talking about.

TKanzler ... looks like we were typing our posts at the same time! I think you hit the nail on the head ... I'm going to look and see if I can remove the check valve and route a new output hose with a high enough loop to reduce backflow ...

We'll see what happens!!

 

[MitchM]

1)i had a flowback problem on my last boat (not a hunter.) finally solved it by mounting a beltdrive bilge pump out of the bilge. if the backflow cycling really bothers you, a belt drive diaphragm (like the par jabsco for about $350) will eliminate the flowback. the belt drive pumps mount way up high out of the bilge itself, and there is very minor flowback from the pump into the bilge, unlike the rule submersibles. with the rule, the flowback volume is the entire length of the bilge pump exit hose to its highest point . and you should not put a check valve into the bilge pump exit line , per abyc
2) have you thoroughly cleaned the float switch, and then pulled the pump to double check the wiring connection into the pump body is tight and secure. sometimes the floatswitches get some flotsam (or jetsam) trapped under the hinge so it is hard for the switch to move up enough to trigger the bilge pump 'on.'.

 

[Witzend]

In writing this out, I now start to wonder what would happen if I added water to the bilge to the point where the float switch kicked in by itself with no manual intervention. Maybe a higher water level would force air out of the pump ???? I've got to test this out.

I keep a dry bilge, so I had the same problem, and yes adding more water solved it, so it was in my case an air lock issue.

 

[Morgan30]

The pump will only work, that is not just turn, but move water if it is at a certain level. It needs maybe 2 inches of water. Otherwise it is spinning air.