Bilge Pump

[Element]

Just ran into an issue with the bilge pump on my 2005 240. The bilge pump was replaced a couple of years ago and worked fine a month ago when I was cleaning out the bilge. Went to to do some more cleaning the other day and the bilge pump would not turn on with water in the bilge. The dash switch also does not turn the pump on.

Batteries are fine, checked the bilge pump lugs after the main battery switch and there is power to them regardless of whether the switch is on or off, which is fine. The bilge pump circuit breaker is not popped out, but interesting enough the led light for the bilge pump is the only one that does not turn on when the switch is flipped. All other switches work.

I've gone through the wiring harness schematic from the manual and looked at any visible wiring to determine whether there is a fuse somewhere in the system and have not found one. Have not pulled the pump to checked if there is power to it, as access is difficult at best for my frame.

Looking for some help/suggestions .....
If anyone has a detailed wiring plan for this model, would greatly appreciate it.
Is there a fuse somewhere in the system that I'm not finding?
There is a connector that feeds wires under the motor (per pic), that's a bit tough to reach, does anyone know whether it feeds the bilge pump?
I can swap out the breaker as a test. Does the always on power to the bilge pump feed back to the under dash circuit breaker?

Any thoughts would be appreciated. Thanks.

[Titaniumboy]

If anyone has a detailed wiring plan for this model, would greatly appreciate it.

Here are the electrical drawings for the 240. Be warned that the drawings are not laid out in a manner which is very useful for troubleshooting. I traced out the bilge pump circuit as shown on the drawings last month in an effort to better understand how that circuit works, but my sketch needs cleaned up before posting here.

viewtopic.php?t=6488

Is there a fuse somewhere in the system that I'm not finding?

There is a 30 Amp circuit breaker labeled “Bilge” next to your battery selector switch and a smaller circuit breaker located in the helm console.

There is a connector that feeds wires under the motor (per pic), that's a bit tough to reach, does anyone know whether it feeds the bilge pump?
I can swap out the breaker as a test. Does the always on power to the bilge pump feed back to the under dash circuit breaker?

Cobalt inexplicably derived what they call the “bilge pump hot”, which is what powers the bilge float switch, from the hot side of the dash bilge pump switch. In other words, rather than grabbbing power for the float switch directly from the batteries (which are rather conveniently located right next to the bilge float switch) Cobalt decided to run the “bilge pump hot” wire all the way from the back of the boat all the way to the dash, and then run it all the back aft again.

And to add insult to injury, that “bilge pump hot” wire goes through at least five different connectors on it’s epic journey.

Lots of good info in the thread “Bilge pump not working 232”. viewtopic.php?t=6527

[Element]

Titaniumboy,

Thanks much for the prompt reply back and the schematics. Those should keep me busy this evening. Your info on the "bilge pump hot" is interesting. I agree, not sure of the benefit of running a hot wire all the way to the dash and then back to the float switch, unless the idea was that you can run the bilge pump with the dash toggle switch without the battery switch being turned on. I'll see if I can put a meter on the switch to see if power is on with the battery switch being off.

I'll head back out to the boat tomorrow to check the 30 amp circuit breaker at the battery switch. I'm relatively sure I checked both sides of the breaker and they were both hot, but will recheck them. I have a couple of "spare" circuit breakers on the dash, for accessories so I'll check the size and if the same will swap them out as a test. Will update the post with what I find. Thanks again.

[Titaniumboy]

Good luck and let us know what you find.

No matter what Cobalt had to run a wire up to the helm for the helm bilge pump switch. That wire is labeled on the drawings as “Bilge Power”. After the helm bilge pump switch there are two wires; one is labeled “Bilge Pump Switch” and the other is labeled “Bilge Pump Hot”. Its much easier to understand if I ever get that bilge circuit sketch uploaded.

There is a connector that feeds wires under the motor (per pic), that's a bit tough to reach, does anyone know whether it feeds the bilge pump?

I could not find a picture of that connector in my files, but the wire colors match up perfectly with the 240 electrical schematic. I need to take another look in the Bilge and see if my bilge pump connector is a waterproof connector like yours. If so, it would be the only waterproof connector on the boat except for the Mercruiser stuff.

11EA3FB1-97D5-4AAC-B2C3-BA250664351F.jpeg

By any chance does your 240 have any of the cool extras like transom shower, cockpit heater, flag pole, etc?

[Edited to clarify the wire labels and added the connector picture]

[Element]

None of the extras you called out. For the flagpole, is that for a light or a flagpole mount? I picked up a stainless flagpole mount, just haven't had a chance to install it. The original owner did have a central drain manifold installed (I can post a pic if interested), that has flex hoses running from all of the motor drain ports that makes winterizing a breeze.

Thanks again for the schematics. As you called out, the hot to the bilge pump dash switch is connected to the bilge pump hot wire that goes to the pump. The only other things on the hot feed are the 30 amp breaker at the battery switch, which I believe is good, and the 5 amp bilge pump circuit breaker. I’ll check the hot side of the switch tomorrow and if there is no power, then it would also explain why the led does not turn on with the switch and would lead to the 5 amp circuit breaker. The only other 5 amp circuit breaker looks to be for the wiper, so I can swap those temporarily, losing the head blower which is on the wiper circuit until it is replaced.

I also want to trace the wires from the pump itself to make sure there isn’t an issue at the pump since it was replaced. More to come.

[Titaniumboy]

I was asking about a flagpole mount, which I haven’t gotten around to installing yet.

What is “winterizing”?

We’re thinking of moving soon to a place where winterizing would become necessary, so I would be interested in seeing your central drain system. Is that an aftermarket setup, or did the previous owner design his own? Merc or VP engine?

I keep forgetting the year and model of your boat. Perhaps you could add that info to a signature line?

I finally cleaned up my sketch of the bilge pump circuit. As you can see from the bilge pump circuit, the red indicator light can be energized by either the helm switch or the bilge float switch. The cause of a non-responsive indicator light would 1) be located upstream of the helm switch, or 2) be a burned out indicator light. Even a bad bilge pump and/or a bad float switch should still allow the indicator light to come on when the helm switch is flipped on.

viewtopic.php?p=109450#p109450


I hope your bilge pumo problem can be solved without having to remove the bilge pump/float switch. On the other hand, I sure would love to know how to remove that SOB. I can’t figure out how to get any tools on the silly thing.

[Element]

I had a chance to make it out to the boat. Started at the batteries and worked my way through the circuits going to the bilge pump. Everything checked out fine including the dash bilge pump circuit breaker. The schematic shows it as 5 amp breaker. My old pump was 1000 gph, listed 4 amp draw and a 5 amp fuse.

Could not get a good view of the back of the bilge pump switch, but suspect the schematic is correct. I believe Cobalt ran the “bilge pump hot” back to the switch as it puts it after the dash bilge pump circuit breaker, so both the “bilge pump hot” and the “bilge pump switch” wiring is protected by this circuit breaker. I would expect that if the “bilge pump hot” wire came straight from the battery, Cobalt would have needed to add another circuit breaker or fuse in that line.

Unplugged the waterproof connector. Testing the leads, the R/BR is always hot and BR/W went hot when the dash bilge pump switch was toggled to on (battery switch did not need to be on). You may recall that the bilge pump led light was not working ….. it works when the waterproof connector is unplugged. Since the pump is dead, I suspect it shorted out internally. I have a new pump motor cartridge on order.

Pulled back the covering on the wires from plug 18. R/BR (always hot) goes to a BR wire, BR/W (helm switch) goes to (2) BR wires and the Y (grnd) goes to a B (black) wire. I suspect that BR from R/BR goes to the float switch, the other wire from the float switch comes back to BR/W and the other BR wire from BR/W goes to the pump. This follows your sketch. If anything you could show the two BR wires both going back to plug 18.

Regarding replacing the pump, assuming your bilge pump is of the same design, there is a pump motor cartridge that twist locks into a pump housing. The housing and float switch are attached to a plate. It’s a royal pain to get to due to the lack of space alongside the motor. My original pump was a Mayfair, but a potential cross reference is SPXFlow Johnson Pump Marine Pump Cartridge. I’m unsure how the float switch is mounted to the bilge pump plate, but suspect it’s screwed to the plate. I believe the plate is then screwed to the bilge floor or transom and may need to be removed as an assembly to access the pump or float switch due to a lack of clearance. It might be possible to replace the motor cartridge without removing the plate, but it looks tight.

The drain manifold looks to be a dealer installed item. It’s most likely overkill for a fresh water boat, but would provide an fast way to drain the motor in salt water boat. I’ll upload a pic in the future.

Not recommending this brand, just passing along as information.
https://www.spxflow.com/johnson-pump-marine

[Titaniumboy]

Wow, you made some great progress. I’ll update my electrical sketch with the wire colors and wire layout that you found.

You may recall that the bilge pump led light was not working ….. it works when the waterproof connector is unplugged. Since the pump is dead, I suspect it shorted out internally. I have a new pump motor cartridge on order.

That is interesting that the pump internal short was enough to keep the indicator light off but not enough to trip the 5 Amp circuit breaker.

Regarding replacing the pump, assuming your bilge pump is of the same design, there is a pump motor cartridge that twist locks into a pump housing. The housing and float switch are attached to a plate. It’s a royal pain to get to due to the lack of space alongside the motor. My original pump was a Mayfair, but a potential cross reference is SPXFlow Johnson Pump Marine Pump Cartridge.

Does my bilge pump look like yours? The first picture looks like the bilge pump is kind of accessible but that was taken with my phone shoved deep into the bilge. The second picture below gives a more accurate idea of just how terrible the bilge pump is to access.

Why did you go with the SPXFlow Johnson as It appears that the Mayfair bilge pump is still available?

8936A604-C43E-4D47-85D5-43B359CE955A.jpeg

EB37095D-D9E1-467A-9E20-A0991F2A4E93.jpeg

I’m unsure how the float switch is mounted to the bilge pump plate, but suspect it’s screwed to the plate. I believe the plate is then screwed to the bilge floor or transom and may need to be removed as an assembly to access the pump or float switch due to a lack of clearance. It might be possible to replace the motor cartridge without removing the plate, but it looks tight.

I have a new pump motor cartridge on order.

I’m confused. It sounds like you have not yet been able to remove either the plate nor the pump motor cartridge, but you bought a new cartridge anyway?

I’m sure sorry that your bilge pump is toast and you’re having to go through all this mess. That said, I’m also very glad that you’re paving the way instead of me.

We need more pictures!!

[Element]

I thought the same with regards to why the breaker did not trip. Once the pump is out, I'll check whether it's has an open circuit or short.

I found a number of pump manufacturer's that make the replacement motor cartridge. I believe the original in my Cobalt was a Mayfair. The local dealer uses Attwood and the Johnson was what came up when I searched for Mayfair. Looking at Amazon reviews, the Johnson motor cartridge had better reviews than Mayfair ..... that's the extent of my research. All of the reviews had instances of pump failures, so I'm considering adding a second pump as a backup.

My bilge pump housing looks the same as yours, which is why I believe that Cobalt used Mayfair units. The float switch is also a Mayfair. The reason I purchased a replacement motor is that it needs to be replaced regardless and I'm hedging a bet that I'll figure out a way to replace it, with a good dose of cussing and scrapes.

In your photo, you can see the black plate that the motor and float switch are mounted to. I took some photos from the other side of the motor and it looks like there are two screws that attach the plate to the hull, one to the bilge hull bottom and the other to the transom back. At least I hope there are only two screws. I'm not going to be able to get to the boat for a week or two, but will take some pics once I get to the point of replacing the pump.

[Stnguyen0919]

how do you guys reach the bottom of the pump and get under , the engine compartment is so small

[Big Block Power]

how do you guys reach the bottom of the pump and get under , the engine compartment is so small

You get a bigger engine with a bigger compartment!

[AsLan7]

how do you guys reach the bottom of the pump and get under , the engine compartment is so small

.
So glad you found us St9.

We do a lot of twisting.
Or in my case we pulled our engine.

And welcome aboard mate.
.