Auto Bilge Not working in 99 Challenger 1800

[cmoore73]

I have a 99 Challenger 1800 that has an issue with the auto bilge

Here are the symptoms and what I have done so far

Auto bilge does not work
Manual bilge (switch) works just fine.... thank goodness...

If I unplug the float switch and manually short the two wires together, the pump turns on... I thought I had found the problem...

I replaced the float switch (which REALLY sucks to get at being that I am 6'3" and weigh 200 pounds). The float switch is not really a float switch, but two screw heads that "short" together when water covers them both.

Still the exact same deal...

any ideas so that I only have to contort myself maybe once more to get at this damn thing?

 

[Lumps]

I have the same problem on my boat. It mine is as a slightly different set up I think. Mine has a separate box with the 2 electrodes. Either way it's the same symptoms. If I ground the ends it turns on. But the water by it's self is not enough of a circuit. Not sure the solution but I may replace the pump with one with a built in float or the auto kind the spins up every once in a while. I am still trying to figure out how to fix it though

 

[cmoore73]

The sensor is separate from the pump, but mounted to the bracket on the side of the pump.
here is a pic of the switch itself:


I wouldn't have an issue with replacing the whole deal with one that has a built in float, but I don't want to lose the functionality of the switch at the helm to manually turn it on as well.
I would just really like to get what I have going.

I see in the electrical diagram for the boat that the water proximity sensor appears to go to a "water detection circuit" somewhere in the MPEM.... maybe???
and there is a relay involved as well. Maybe the relay coil is so weak that the water won't turn it on, but grounding the ends does....

I believe that if the 3 amp fuse was blown, then the pump wouldn't work at all... or.. at least the auto wouldn't work if the switch was jumped..

The other thing that I would add would be that I "shorted" the switch out with a screwdriver across the terminals to emulate water, but it did not turn on either.

the only way that it works in automatic is if I jump the two pins in the auto switch plug together.

 

[cmoore73]

Testing the old switch

No water - Open

Switch in water - resistance fluctuated... 2 MOhms to 93kOhms

Switch out of water but shorted with a screwdriver - .1 Ohms

 

[Seadoodoc]

Huge variables in answer to that question. You might forum search bilge pump questions, I got some really long winded answers to perfect set up. [emoji41]

 

[Lumps]

I was at walmart the other day and the pump they had had 3 wires. I believe it was ground, auto and manually on. I haven't looked at the wiring diagram yet so I don't know how well this will work in.

 

[Seadoodoc]

Yes lumps. That is perfect pump. As pictured above. Boat cycles on float switch if left unattended. But cycles every 60 secs while riding being load specific. I have sunk a ton of shit!

 

[Seadoodoc]

Dont run a toggle switch. Make it idiot proof.

 

[Seadoodoc]

Here is "worry free" bilge pump formula per Seadoc dumbarse antics on sinking and losing multiple boats. Buy the Rule 3 wire Electronic Computerized pump. Wire to ign on . It cycles every 60 secs. No water and it shuts off. If it senses load on pump it keeps bilging. Third ingenious Rule pump wire is float switch wire input. Float switch triggers pump if you leave boat at dock for days on end. Everything is automatic and idiot proof. Works wonderful on my continually sinking Wakesetter. Wanna hear my Challenger boat engine survival story if your interested.

 

[Lumps]

I just realized it makes a difference that this is the seadoo forum and not the mercury. anyway, mine is very different and doesn't have the "water level circuit" in the computer like yours does. I am sorry if I interfered

anyway, this is what mine looks like:

it has broken off its screws but it would have normally been screwed to the wall of the engine bay near where you would expect the pump to kick in. anyway, I forgot it is just one screw exposed the water so I have no idea how this was intended to work. touching the bolt with a screwdriver will turn it on but not just being in the water anymore.

 

[Seadoodoc]

https://www.wholesalemarine.com/rul...Z-3iwN27b8g8pBPzAieTF_mJC8dkv4XREEaAirW8P8HAQ. This piece right here is an absolute robust work horse. Had some for 25 yrs banging around in race boats. Use 3m heat shrink but connectors.

 

[Lumps]

I found a replacement part for mine on ebay, but the shipping and duty etc make it too expensive. I am thinking of using the floating switch specified above. if I were to mount these in the bottom of the hull, how do I make sure I do not go all the way through? how thick is the hull down there? should I just use marine adhesive or epoxy etc?

I don't want to ruin my hull but I want to have a working pump too though

 

[Seadoodoc]

The hull consists of inner and outer layer glued together. Many spots have foam injected between layers for flotation. Im not really specific on jet boats but pwc I drill through inside then test depth. We build our own carbon hulls.

 

[Lumps]

I don't know how things are progressing with your issue. I have mine fixed now. the issue is that the exposed wires on my are not equivalent to yours. anyway, I bought a "Johnson Ultima bildge switch". it is functionally equivalent to the one in that came in the boat. the only difference is it had 2 wires and not 3. weird? I guess its electronics ground through the pump? not sure.

anyway, I had to mount it in a different place because it turns on when the top of it is covered and not the bottom as the previous one. this caused the pump to turn on when there was waaay too much water in the hull. any way there are 2 circles drawn on the front. when both are covered with water, it turns on. it will turn off when the water gets pumped below the level of the bottom circle. so far it works.

I don't think on your boat you will be able to just place it in line with your existing sensor. I suspect you would need to run a line from always on +12v (with a fuse) to the switch and then to the plus side of your pump. this assumes that your negative from your pump is always grounded. I think this is the case but confirm with your wiring diagram.

anyway, let us know what you work out.

 

[bflowers1971]

I also just fixed my auto bilge by cleaning the contacts on the harness from the water sensor, they were pretty crusty. Works as designed now.