Help: '06 21 LSV Bilge Blower Problem

[srab]

So, after refueling last week, I turned on the bilge blower while still at the fuel dock at my marina.  My wife and I noticed that, at one point, the blower seemed to stutter and slow for 10 seconds or so, but it picked up again and worked fine after that.

We went out again this morning, and it did it again.  Already finished skiing, we headed back to the marina, but, before we arrived, the light on the blower switch turned off and, after throttling down to "no wake" speed, it was obvious the blower had stopped working completely.

Once back in my slip, I pulled the toggle switch panel off, gaining better access to the back side, and switched the leads from the bilge pump over from its switch to the blower switch.  I flipped the re-wired blower switch to the "on" position and the switch light came on, as did the bilge pump.  So, I concluded that the blower switch is good.

I pulled the blower motor and brought it home, expecting to have to order a new one.  But, when I  tested it here at home using a 12 volt battery, it seems to be working fine!

It says "use 8 amp fuse" on the side of the blower motor housing, so I'm assuming there is a fuse somewhere that I missed.  Any idea where to look?

It strikes me as odd, though, that a blown/bad fuse would have allowed the stuttering/slowing that we noticed before the failure.

But, if the switch works and the motor works, what else should I be looking for?  To the best of my knowledge, I've never had any wire-chewing critters inhabiting my boat, but I guess there could be a new ground fault somewhere along the harness?

[Kmfish87]

Since you already know the blower is good find and check the fuse first, if it's good check for power at the fuse. then check the power at the wires at the blower motor with the switch in the "on" position. If no power place one probe on a known good ground (alternator or starter ground) and check both blower wires for power. If you have power then you need a new ground wire. If no power run a new wire from switch/fuse to the blower.

[srab]

Update:  So, after fiddling around with the blower motor a bit more, I found that, while it seemed to run fine hooked up to a 12 volt battery, when I disconnected, on occasion, I'd get a telltale B-R-R-R-U-P with fan blade tips hitting the housing.   

I ordered a replacement through the local Nautique dealer (they are closer).  Ended up with a Detmar blower because it most closely matched, dimensions-wise, the blower that I removed.

There was no inline fuse.  The breaker panel below the throttle showed a tripped breaker, appropriately labeled "blower." 

Install was pretty simple.  The only thing that complicated matters was that the holes on the mounting feet on the new blower didn't line up perfectly with those on the old one, easily rectified with a power drill before I even headed out the door.

Interestingly, it was the first time that I actually looked at the blower ducts and how they are routed.  On my boat, the blower motor sucks air up from the bilge, through the blower, and out the rear starboard-side corner vent.  The rear port-side corner vent is the intake side, its hose looping down into the bottom of the bilge, zip-tied together with the other hose so the openings of both are close together.  As air is drawn out of the bilge with the blower on one side, it is passively drawn into the bilge on the other. 

So, if I were to leave the blower on while gassing up on the starboard side, there wouldn't be a problem.   But, if I were to gas up using the port-side access, I could conceivably be drawing gas fumes down into the bottom of the bilge while filling the tank.  Those fumes, of course, would then be taken up by the other hose and sucked up through the blower motor.  Probably not a good idea!