2007 SV211 ballast belly tank won’t empty past half full

[ROCKer]

Can someone give me the steps to diagnose the issue. I’ve let it run several times and gauge won’t go below half. Thanks in advance.

[homer12]

Are you sure the tank still has water or is it a gauge issue? Does the pump still run and spurt water at the end like it’s empty or just quit?


Sent from my iPhone using PLT Nautique

[ROCKer]

I’m not sure if it’s empty or not. Purely going off the gauge reading. Is the belly tank in the ski locker? Can you see how much waters in it?

[Shawn Henderson]

You can try swapping the belly gauge with the port or starboard gauge. If it turns out the gauge isn't the issues then remove the rear floor hatch and you can easily access the belly tank sending unit. Pull the sending unit and slide the float up and down to see if the gauge corresponds with the movement of the float. If you find the gauge isn't moving with the float then you can check the sending unit with an OHM meter (240-33ohm). The float on the sending unit is supposed to be magnetic for what ever reason all 3 of my ballast tank sending units became un-magnetized. You might want to check that as well if you find the gauge movements are not corresponding with the float placement. The magnetic float trips switches on a circuit board inside the shaft of the sending unit. If you find the float is no longer magnetic then try running another magnet down the shaft to see if your ballast gauge corresponds with the movements to confirm you only need another sending unit.

Once last thought and this might be the easiest way to check that the tank is empty. Leave enough water in one of the other ballast tanks so the pump for that tank will still discharge. Then at the pumps unplug which ever pump you selected from the wiring harness and plug your belly tank pump into that plug empty the tank then swap the plugs back.

[homer12]

Good advice above. However, by just running it, you will notice when getting towards the end the water flow out the side changes from a steady steam to just spitting out. That should tell you it's getting empty. As was said above, if you just pull the sending unit from your belling tank (remove rear floor section) you can shine a flash light and see if empty. The sending unit could also be bent (seems like a common problem) preventing the float from going all the way down when empty.

[ROCKer]

Thanks for the help and I'm going to check it out this afternoon. I'll let you know what I find. I do remember that the dealer replaced one of the gauges before I got the boat this spring, so that might be a good place to start. do they normally go out that easy?

[ROCKer]

Finally got back to the boat and swapped gauges. Both gauges showed half full for the belly tank. I’m going to pull the floor and check the sending unit. Thanks for all the help.

[ROCKer]

Got the floor removed and took out the sending unit. The unit appears to be working and there was water in the tank. When I raised the sending unit the gauge worked correctly. I started playing around with the ballasts switches and noticed that the belly tank lights are working on the console, but the pump is not turning on? Any ideas on what could be the problem?

[charlesml3]

Start by finding the electrical connection to the pump and see if it's getting voltage when the switch is on. If it's getting power, then the pump is bad.

[ROCKer]

Thanks and I’ll get over and check it out. I’m assuming they have a quick connector attached to the wiring.

[charlesml3]

Thanks and I’ll get over and check it out. I’m assuming they have a quick connector attached to the wiring.

Yep. It won't be more than a few inches from the pump.

[distinguishedmotorsports]

bent sending units occur far more frequently when you place fat sacks on top of factory hard tanks. ask me how i know...

also, you can flip connections amongst the pumps and see if its a pump issue or a wiring issue.

[ROCKer]

Went out on the boat this afternoon. Took my voltmeter and checked that middle pump/belly for voltage. It was getting 12.5v. Then I looked up the part on NautiqueParts and it was $300. Are they really this much and what’s the life span of a pump? Do I replace with the same part or is there a better pump?

[ROCKer]

Got to remove the pump after work. I took it completely apart and cleaned the brush contacts. It will now run on a battery and I’’m going to plug it back up tomorrow for a test. It was a pain getting to the screw head on the back side of the plate that they are mounted to.

[ROCKer]

I learned a valuable lesson and should have swapped plugs out before removing. The pump did NOT work when I plugged it back up. I took the plug from another pump and hooked it up and it worked fine. The bad connector shows 12.5 volts, but does not run the pump. Could it be the relay not allowing enough current to flow?