Hunter 356 Bilge Pump problem

[SwanAround]

In my 2004 Hunter 356 the bilge pump is having trouble pumping the water up the 5' it needs to go to get up and over the through hull.

Configuration

• Separate float switch (appears to be working properly)
• pump leads to a currogated white plastic hose that goes across to the port side, up about 5 feet to where it is 6inches or so above the through hull, a 180degree turn back down to the through hull, and then a 90 degree turn to head out of the boat.

It definitely sends water up into the hose, but it seems to then get into an equilibrium where it can't pump any more water and yet it is not expelling any out of the boat. When the pump turns off, the water comes back down the pipe. When the water level is right on the border of the float switch, this causes a cycling. When the water gets higher, it just stays on...stuck in that equilibrium situation. No water comes out the through hull

My first thinking was that the pump had deteriorated to lower pumping capacity. I replaced the pump, but that doesn't seem to have solved the problem.

My next thought was blockage. I sent a fish tape up the pipe and I think I got all the way TO the through hull, but not able to get out of the through hull though. Thinking there might be some sort of valve there or possibly just too many tight turns. So, that didn't solve the problem either.

My next move might be to use a plumber version of fish tape and disconnect the plastic hose from the through hull to at least confirm that part is not blocked.

Any thoughts on what to do next?
Anyone know how the through hull is configured? I tried sending the fish tape down from the outside, but that didn't seem to work. Thinking there might be a valve there to only let water out.

Cheers,
Swan

 

[Sailvayu]

It sounds like a blockage possibly at the outlet thru hull. there normally is a loop near the thru hull inside. This would be hard or impossible to run a fish tape thru. Try using a garden hose to flush it backwards from the out side. You might have to remove the hose from the thru hull on the inside, this should not be hard to do if you can get at it ok.

 

[Jerry Clark H356 SV Persi]

It sounds like you have a blockage in the line. First, I would try a shop vac over the exterior thru-hull. If that didn't work, I would try a water hose from outside, starting with very low flow and then increasing. Probably a dirt dauber nest or other similar blockage near the outside. The water remaining in the hose always falls back into the bilge. There is no check valve in the line unless it was modified by the previous Owner.

I haven't looked at that thru hull in a long time, but believe it can be accessed from the inside by lifting up the starboard salon cushions.

 

[chuckwayne]

As Jerry said, there normally isn't a check valve on the thru hull but there is a very tight 180 degree loop. I don't remember exactly, but it's either behind the settee back cushion or accessible behind the breaker panel. check for a blockage around the valve-it is a popular nesting place

 

[SwanAround]

Thx guys. The thru hull is behind the breaker panel. Good to know that there is not any kind of valve there. Makes troubleshooting list shorter

Some great ideas provide. Think I will try in the following order:

1. Shop vac from outside hull
2. unhook hose at thru hull and shoot water out thru hull
3. unhook pump and shoot hose down hose from thru hull to bilge
4. Try another pump

 

[Dubai]

Thx guys. The thru hull is behind the breaker panel. Good to know that there is not any kind of valve there. Makes troubleshooting list shorter

Some great ideas provide. Think I will try in the following order:

1. Shop vac from outside hull
2. unhook hose at thru hull and shoot water out thru hull
3. unhook pump and shoot hose down hose from thru hull to bilge
4. Try another pump

Surprised that there is no non return valve. I just changed the bilge pump on my 326 and there is definitely a non return valve. Nothing too sophisticated, a small plastic T piece in the hose, housing a small rubber ball held in place by a spring. Pump pressure is enough to overcome the spring pressure so water flows OK, when pump switches off, the spring pressure is enough to push the ball into position to prevent water from returning back to the bilge.

 

[seadaddler]

Maybe

The pump might just have lost it's power to pump out tthe bilge,have you tried disconnecting the pump and poping the bottom off and cleaning and how about using air pump from the dinghy to pump out the hose going to through the hose and out the outlet at the hull.
I replaced my float switch and pump recently due to a crack in the pump where the hose connects and also tried cleaning the float switch which was very gumed up with a film of dirt and so for piece of mind replaced both.
Nick

 

[SwanAround]

Pump power

The pump might just have lost it's power to pump out tthe bilge,have you tried disconnecting the pump and poping the bottom off and cleaning and how about using air pump from the dinghy to pump out the hose going to through the hose and out the outlet at the hull.
I replaced my float switch and pump recently due to a crack in the pump where the hose connects and also tried cleaning the float switch which was very gumed up with a film of dirt and so for piece of mind replaced both.

Thx Nick. That makes sense. I already replaced pump once last year. Have been struggling to explain why second pump would have worked at first and now in same predicament as original pump. Some "gumming" in both pumps could be the culprit. I have checked that the impeller spins freely and it seems to, but I have not taken the bottom off. Will try that too.

 

[Ken13559]

Perhaps to check the electrical for bad joint. 12V at pump side when it is operating.

 

[tomgrigsby]

Perhaps to check the electrical for bad joint. 12V at pump side when it is operating.

X2
A corroded wire will drop current enough that the pump will run but not at full speed, thus not enough power to get the water out. Also, low battery will cause this symptom.

 

[seadaddler]

Float switch

My float switch was the part that gave me a problem being all gumed up andnot letting it work freely and other than a cracked hose connection the pump worked good.
Like already mentioned check the wiring too and any connections,does the manual switch for the bilge pump work OK,normally the bilge never gets completely dry from the bilge pump and when almost empty a certain amount of water always flows back in.
Nick

 

[Bob 04 H260]

Surprised that there is no non return valve. I just changed the bilge pump on my 326 and there is definitely a non return valve. Nothing too sophisticated, a small plastic T piece in the hose, housing a small rubber ball held in place by a spring. Pump pressure is enough to overcome the spring pressure so water flows OK, when pump switches off, the spring pressure is enough to push the ball into position to prevent water from returning back to the bilge.

The non-return valve, (aka as a check valve) can be a source of problems as well as reduce the flow of your bilge pump by 50% or more. Unless you really need it better to live without one.

Bob

 

[Dubai]

Perhaps to check the electrical for bad joint. 12V at pump side when it is operating.

Hi Ken

As a fellow 326 owner, can I ask you if you have a non-return valve fitted in your bilge pump hose.

Cheers

 

[SwanAround]

Electrics?

X2
A corroded wire will drop current enough that the pump will run but not at full speed, thus not enough power to get the water out. Also, low battery will cause this symptom.

I disconnected the bilge hose from the through hull and then ran a coat hanger through the through hull to ensure no blockage. Also ran the shopvac on the hose and it seemed to be sucking full power. I even poured some water into the hose and blew it out manually. Some back-pressure, but not too bad considering I was blowing up 5 feet. Disgusting I know to put lips on that hose, but I am getting desperate.

I was so discouraged with not finding the problem that I went and got a new pump. That also didn't solve the issue.

tomgrigsby idea about decreased power now seems like my best lead. My battery is fine, but a connection may be weak somewhere. I am going to get a multimeter tomorrow and check the power levels. When checking the connections, I found a crimp connection that wasn't completely locked in. My hopes went way up, but even after re-crimping I am still having the same problem.

Don't think I have mentioned it yet, but I am using the Rule 27D. It indicates 1100GPH. If I just pump the water through the pump with no hose connected, how fast should it come out? Tough to be precise with that. Perhaps how far would it shoot horizontally? My pump discharge seems to be going about 3-4 inches before gravity brings it back down to the source

 

[Ken13559]

Hi Ken

As a fellow 326 owner, can I ask you if you have a non-return valve fitted in your bilge pump hose.

Cheers

No non-return valve fitted. The drain hose goes alittle higher than the thru-hull then made a loop and down to the outlet.

 

[Ken13559]

I disconnected the bilge hose ......went and got a new pump. That also didn't solve the issue.

tomgrigsby idea about decreased power now seems like my best lead. My battery is fine, but a connection may be weak somewhere.....r re-crimping I am still having the same problem.

....

How about getting a new correctly sized wires from battery to your old pump. no need to lay properly just run over the saloon floor. give a long length to simulate actual run length (for voltage drop across wires). See how it perform. If its good, then your old wiring is the problem.

 

[SwanAround]

How about getting a new correctly sized wires from battery to your old pump. no need to lay properly just run over the saloon floor. give a long length to simulate actual run length (for voltage drop across wires). See how it perform. If its good, then your old wiring is the problem.

Started having some trouble with my stereo as well. Took off the wiring harness and stuck a multimeter into the pins. Only getting 3volts. I have two different battery monitors and they are both showing over 13v. Put the multimeter right on the battery... Also 13v.

The refrigerator, cabin lights, etc... That are all on the same 12v panel. Seem to be working fine. Any ideas?

 

[Dubai]

No non-return valve fitted. The drain hose goes alittle higher than the thru-hull then made a loop and down to the outlet.

Cheers Ken