[rose_surfer]

My bilge blower has always seemed to draw an awful lot of current - maybe a couple of amps or so, and it even draws down the voltage on the bus when it's on.  The other day I flipped it on as part of my normal starting procedure and it wouldn't start at all.  I figured the motor must have been on it's last leg and was now shot.  

Anyway when I opened up the compartment to take a look, I noticed that I've actually got three blowers all wired together (see pic) in the bilge.  Is this normal for a 3100 open?  Assuming my situation is...abnormal...what should I replace it with?  Can I use something like this 4" 220CFM shurflo in line blower (
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) or do I need one of the much more expensive radial style blowers?

   

[Uhehner]

Just a guess but one is for each main engine and one is for the generator area.  Capt. George

[czarcone]

Sounds familiar, prior to launch I flipped the switch & blower runs for 30 secs, then trips breaker.  Reset & runs for another 30 secs.   When I get to slip, I take a look & find two blowers, one behind the other.  I was able to get direct replacements ( Jabsco #36740 series).  No telling how long the one blower has been seized & rusted open.  Pretty straight forward replacement except for the extremely inhospitable location.  I had to lay on my back across port engine & work upside down in order to manipulate hose clamps, wiring & mounting screws.  Hoping to not look at them again for another 20 years! 

If motors are the same, they each draw 6.8 amps.  Next year I'll attempt to tackle that cracked sanitation hose.  Good luck!

[rose_surfer]

Thanks for the suggestion on the replacements. I'll look them up. Sounds like another mysery filled "hot yoga" projects.

[rose_surfer]

Turned out to just be a bad switch at the helm. I bought the closest replacement I could find at west marine - an illuminated red/white toggle. However I couldn't figure out how to wire it such that it would switch the blowers on and off and illuminate red when on and white when off. The switch I pulled out had three terminals - two yellow wires attached to two terminals and then two grey wires connected together to the third. The new switch has four terminals. I tried every combination I can think of and can get it to switch the blower or can get it to light up but not both. I believe one yellow wire must go to the battery and the other to the blowers, which would make the grey wires the light circuit. I'm thinking maybe I need to jumper the hot wire to the fourth terminal. But perhaps I should try separating the two grey weed and putting them on different terminals. If anyone has done this let me know if you remember the right combination.

[Uhehner]

A picture of your switch and wires would help. Also what is the wire size? Does the switch packaging have a wiring diagram? What is the part number of the switch? 
If you Google marine wiring colors you will see that brown with a yellow stripe is for blowers, grey is for nav lights, purple is for instrument lighting. My 88 follows this color code so your 89 should also. One more question, did you buy a switch rated at 20 amps or more?
Capt. George