Mercruiser 3.0 bilge pump, fan dead?

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westmich1

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1997 Alpha One 3.0 135, boat starts and runs but bilge pump and blower fan will not work. Never happened before. Battery strong. Water in bilge area after a hard rain. Anyone have any troubleshooting ideas? Boat getting heavy and tired of manually fanning engine bay pre-start!! Thanks!
 

Blk-n-Blu

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Re: Mercruiser 3.0 bilge pump, fan dead?

Check the fuses?
 

westmich1

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Re: Mercruiser 3.0 bilge pump, fan dead?

Check the fuses?

I did check the fuses. appears that the blower fan fuse is blown but the bilge pump fuse is ok. I put other fuses from other circuits in bilge pump and blower spots and no improvement. Not same sized fuse, but close. They are next to each other on fuse panel--do they need to both be working for either to work? DO the fuses need to be exact size of original just to trouble shoot?

After I empty the bilge water I will check ground connections to pumps and blower--where are they?! Thanks.
 

Bt Doctur

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19,376
Re: Mercruiser 3.0 bilge pump, fan dead?

Is there a automatic float switch in the circuit?
Hot wire the pump to check it?
12V available at the pump circuit?

NORMALLY, the bilde pump circuit is on the stbd side of the transon, a black wire and brown wire.,and maybe a red wire to the battery from the float switch.
Most troubles are from using the non-sealed crimp connectors that most people never seal with liquid tape or just plain tape.
 

westmich1

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Re: Mercruiser 3.0 bilge pump, fan dead?

Is there a automatic float switch in the circuit?
Hot wire the pump to check it?
12V available at the pump circuit?

NORMALLY, the bilde pump circuit is on the stbd side of the transon, a black wire and brown wire.,and maybe a red wire to the battery from the float switch.
Most troubles are from using the non-sealed crimp connectors that most people never seal with liquid tape or just plain tape.

--

NEW problem now--after bailing manually, the boat makes no noise when I turn the key, and the gauges seem to have stopped working. New battery, the battery guage if flat at zero, no movement on any gauge when I turn the key and no noise. Boat ran all morning. May have wetted battery terminals when bailing.

The radio works, tilt/trim works, just the gauges don't move. Battery seems not to be the issue. Wet connections somewhere?

Any ideas? I just want to pull out of the water and drain then work on dry land. Jeeze....
 
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Silvertip

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Re: Mercruiser 3.0 bilge pump, fan dead?

There are two electrical systems on a boat. One main feed runs from the battery through a fuse or circuit breaker at the battery to the fuse panel. The fuse panel has individual fuses for the various accessories. There is a separate circuit that is part of the engine harness that runs from the engine to the shift throttle control box and ignition switch. The ignition switch activates the gauges but does not generally have anything to do with the fuse panel. If the gauges don't work, check the circuit breaker at the engine. If it is tripped there will be no power to the gauges or the starter solenoid and therefore you experience what you are experiencing. You might also check (as in disconnect, thoroughly clean, and reconnect) both ends of both battery cables. A loose or corroded connection at those cables will also kill the engine part of the system.
 

westmich1

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Re: Mercruiser 3.0 bilge pump, fan dead?

There are two electrical systems on a boat. One main feed runs from the battery through a fuse or circuit breaker at the battery to the fuse panel. The fuse panel has individual fuses for the various accessories. There is a separate circuit that is part of the engine harness that runs from the engine to the shift throttle control box and ignition switch. The ignition switch activates the gauges but does not generally have anything to do with the fuse panel. If the gauges don't work, check the circuit breaker at the engine. If it is tripped there will be no power to the gauges or the starter solenoid and therefore you experience what you are experiencing. You might also check (as in disconnect, thoroughly clean, and reconnect) both ends of both battery cables. A loose or corroded connection at those cables will also kill the engine part of the system.

Thanks for the tip--it wasn't the circuit breaker, so I will check the battery connections in the morning and reply. The battery did get wet from bailing and I wonder if that could have done it...
 

westmich1

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Re: Mercruiser 3.0 bilge pump, fan dead?

There are two electrical systems on a boat. One main feed runs from the battery through a fuse or circuit breaker at the battery to the fuse panel. The fuse panel has individual fuses for the various accessories. There is a separate circuit that is part of the engine harness that runs from the engine to the shift throttle control box and ignition switch. The ignition switch activates the gauges but does not generally have anything to do with the fuse panel. If the gauges don't work, check the circuit breaker at the engine. If it is tripped there will be no power to the gauges or the starter solenoid and therefore you experience what you are experiencing. You might also check (as in disconnect, thoroughly clean, and reconnect) both ends of both battery cables. A loose or corroded connection at those cables will also kill the engine part of the system.

Fuses and breaker fine, still doesn't start.

If the starter or cellonoid get wet can that cause lack of power to gauges and cause the boat not to even make a click when the key is turned? Last year I had water in the bilge as well after a rain (I need a good cover!) and the starter got wet and after just 3 weeks of not using it the shop told me the starter was rusted and no longer serviceable and charged me for a new one. The starter was only 6 months old.

What I don't understand is how a boat motor and its parts can be ruined by exposure to a bit of water. How much water is too much water?

Thanks.
 
Joined
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Re: Mercruiser 3.0 bilge pump, fan dead?

i had the same problem even though fuse look good change them put crosen spray every where grease every thing change all fluids and charge your battrery there is so much to go from all the time there a great thing to have but a massive money pit
 

Bayliner1952

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Dec 2, 2010
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Re: Mercruiser 3.0 bilge pump, fan dead?

It seems you may have a few problems. One thing I can help.
I had the issue of my engine bay exhaust fan fuse tripping evry time I went to use it. I removed and hardwired to the battery and it worked fine. I then reinstalled and had the same issue. I then realized that since the housing of the fan is plastic and the hose clamps go around this, that when I tightened it, it was clamping the fan inside of the shroud. Losened up a bit and it solved my problem.
It's probbly not related to your issues, but may help others, Good Luck!
 
Joined
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Messages
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Re: Mercruiser 3.0 bilge pump, fan dead?

--

NEW problem now--after bailing manually, the boat makes no noise when I turn the key, and the gauges seem to have stopped working. New battery, the battery guage if flat at zero, no movement on any gauge when I turn the key and no noise. Boat ran all morning. May have wetted battery terminals when bailing.

The radio works, tilt/trim works, just the gauges don't move. Battery seems not to be the issue. Wet connections somewhere?

Any ideas? I just want to pull out of the water and drain then work on dry land. Jeeze....

Check all your grounds to be sure they are tight and not corroded or loose, check for voltage at the gauges using an ohm meter switch to DC to check for power, trace back to the fuses and make sure the fuses are not corroded or broken. Check the fuse panel for power, and see if the connection from the negative buss if so equiped and postive leads to the panel from the battery are tight.

Good luck to you, I had my whole wiring harness fry on me this summer in my jet boat so I feel your pain man.


Hope you find your solution soon.

Mike
 
Joined
Nov 5, 2009
Messages
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Re: Mercruiser 3.0 bilge pump, fan dead?

--

NEW problem now--after bailing manually, the boat makes no noise when I turn the key, and the gauges seem to have stopped working. New battery, the battery guage if flat at zero, no movement on any gauge when I turn the key and no noise. Boat ran all morning. May have wetted battery terminals when bailing.

The radio works, tilt/trim works, just the gauges don't move. Battery seems not to be the issue. Wet connections somewhere?

Any ideas? I just want to pull out of the water and drain then work on dry land. Jeeze....

One other thought, see if you can move/turn the inerds of that bilge pump...it might be stuck or frozen up and just need replacing. A friend of mine was having issues with his bilge pump and it just turned out to be stuck internally. He just replaced it to solve his problem.
 

dhnguyen10

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Aug 26, 2021
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Re: Mercruiser 3.0 bilge pump, fan dead?



I did check the fuses. appears that the blower fan fuse is blown but the bilge pump fuse is ok. I put other fuses from other circuits in bilge pump and blower spots and no improvement. Not same sized fuse, but close. They are next to each other on fuse panel--do they need to both be working for either to work? DO the fuses need to be exact size of original just to trouble shoot?

After I empty the bilge water I will check ground connections to pumps and blower--where are they?! Thanks.

I have the same problem on Mecruiser 3.0. Where did you find the fan fuse? is it closed to fan switch, to fan blower, fuse panel ( which i don't know where it is located). Pictures would be very helpful for me. Thanks.
 
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