Fish Box Macerator Pump

Westie · Posted: Mon Jan 26, 2015 9:42 pm Post subject: Fish Box Macerator Pump

The macerator pump on my starboard fish box stopped working. I have a few questions I could use some help with:
1) is there a fuse? I wasnt able to locate anything in the main panel
2) Can you remove the filter cover in the fish box? Mine seemed pretty tight and I didn't want to break it. My guess is something got jammed in there

Any other fish box advice is welcome. I sure loved it when it was working properly!

Bill K · Posted: Mon Jan 26, 2015 9:52 pm Post subject:

Look for an inline fuse somewhere in the positive wire.

Bill Kelleher

redbaronace · Posted: Tue Jan 27, 2015 12:12 am Post subject:

Could be a fuse. Could also be your pump failed.

We have rebuilt and replaced those pumps several times already on the various tomcats that we owned..

Other times if we turned it on and heard no sound, it was an electrical problem.

Good luck in your troubleshooting.

Pacificcoast101 · Posted: Tue Jan 27, 2015 12:55 am Post subject:

Check the fuse box first. There should be a 20 amp fuse for each pump. If the fuse is good, remove the black rubber cap on the end of the pump and use a flat head screwdriver to manually turn the pump a few rotations. This will sometimes clear any debris caught in the impeller. If this doesn't work you may need to replace the pump. I've had to replace my starboard pump, and the hardest part is getting to it inside the stern.

rogerbum · Posted: Tue Jan 27, 2015 9:30 am Post subject:

While it might be a fuse, I'd bet the pump has failed. I've had 4 Johnson macerator pump failures in my fish boxes in about 3 years. Last year I replaced them both with Whale Gulper Grouper pumps. Hopefully, those will last a bit longer.

Discovery · Posted: Tue Jan 27, 2015 10:00 am Post subject:

The above image is from the "Dreamer" album, but I did the same modification to the fish box's on Discovery. It allows better access to the macerator pumps, also to the bilge pumps.

Use a 6" screw-in type deck plate. Get a plate with an "O" ring, and use 4200 to set the plate in. They don't leak if well bedded with 4200, and contain a good "O" ring.

Westie · Posted: Tue Jan 27, 2015 10:21 am Post subject:

Thanks for the replies. That mod looks good.

BrentB · Posted: Tue Jan 27, 2015 10:23 am Post subject:

Check the voltage at the fuse too

Westie · Posted: Sun Mar 11, 2018 9:18 pm Post subject:

My fishbox macerator pump finally blew! Any advice for a pump to replace it?
I also need a switch for the other pump. My mechanic blew that when debugging the other. The day was actually great as I rewired every battery terminal connection!
Any suggestions?

rogerbum · Posted: Sun Mar 11, 2018 10:07 pm Post subject: