Bilge Pump and Sensor Failure.

[Newf]

Last trip out my bilge pump and sensor failed in my R21EC. Could smell plastic burning in the cabin that only last for a couple of minutes. Finished the trip and found that the bilge pump, sensor and a part of the wiring harness with the inline fuse was toast. The fuse did not blow. Not sure what size fuse was in there as the original pump, sensor and fuse was replaced on a previous failure by an electrical when the boat was fairly new. (The fuse was also melted to some degree so no identifiable marking)

The pump is a Johnson 750 GPH model. My assumption is that it overheated when the pump kicked in while I was travelling and did not shut off after the water level in the bilge got below the sensor. It got quit hot as is evident by the condition of the parts. (photos in album). Not sure why the fuse did on blow unless it was of a higher rating than it was suppose to be.

Given that this is the second occurrence where I lost both the pump and the sensor, I left the sensor off this time and will operate manually from the panel switch in the cabin. I will probably have to pump no more than once on a day trip. The high level sensor and alarm are OK so given that I trailer the boat with no overnight stays on the water I will go this way for now. If my needs change and the boat will be in the water overnight I will re-install a new sensor or even a new style of pump.

Will adjust the drip rate on the stuffing box tomorrow once I'm in the water so that I won't have to pump too frequently. Currently drips every 6 sec while its stationary and I'm told that's too much.

 

[TexasEye]

I'd say 2 to 3 drips per minute...

 

[Newf]

Thanks, I was thinking the same. I've never adjusted it before and had read several post that recommended no drips when stationary and anywhere from a range of 6 to 20 when running. I think I will shoot for a couple of drips when stationary and 6 to 10 when running. Does running speed change the drip rate much?
Tks.

 

[TexasEye]

Really shouldn't see drips while running, a very fine mist, I'm sure the rate increases with RPM but I have never noticed it except on large Boats and both of mine were WET when running. The most important thing is the temp of the box when running...It should not get hot...and make sure the drip rate isn't sinking the boat, I think your drip rate is too high.

Disclamer: I'm new at Ranger Tugs...Really New...so make sure you confirm my info...


http://www.boatus.com/boattech/casey/stuffing-box.asp

 

[knotflying]

I would want to figure out why my pumps were burning up. I suspect that the fuse size was improper. Perhaps the person that installed the replacement never checked for the proper fuse size and replaced it with the size originally inserted.

I am a be a bit concerned that you are choosing to manually turn on the pump. In the event of significant water intrusion you are relying on your memory and high water alarm and the second pump.

Bilge pumps need constant maintenance. Hair, dust and particles tend to get caught in the impeller. The water will not get pumped out and hence the pump keeps pumping and will overheat if not turned off. If the fuse was an inappropriate size then the pump will burn up.

I think I would make sure that I have the appropriate fuse and set up the sensor again, as well as checking on a regular basis that the impeller is clear.

 

[NorthernFocus]

The fuse rating can be determined by the color and size. It's hard to tell from your photo whether that is a standard(nominal 3/4 in) or maxi(nominal 1 1/4 in) size fuse. If standard size and pink then that was a 4 amp fuse, if red then 10 amp. If maxi size and red then it was 50 amp which is WAY too much.

As mentioned in one of the posts above, the pump can burn up simply from running dry. Even if the fuse is properly sized it won't protect from dry run because the pump doesn't pull excessive amps until it begins to melt down. But it does have to run dry a long time to fail in that mode. It will heat up and fail much more rapidly if something jams the impeller but in that case amps go up and the fuse should protect it(assuming it's the right size).

One option you may consider rather than eliminating the auto function is to install an indicator light that lets you know when the pump is running.

 

[Newf]

Thanks Dan, I like the idea of installing an indicator light to show when it's running. Even if I don't install a new sensor I think I will do this.

The fuse is the 3/4 type with a pinkish colour. I found another of very similar colour in my batch of spares and it shows 10amps. The new pump calls for a 5amp so that's what's there now.

Adjusted the stuffing box today and now 1 drip every couple of minutes when stopped and 5-7 DPM when running. On the water for 8hrs and pumped out once for 10-15 sec. Good enough for me. 8-9C temp on the stuffing box. No change in temp at different speeds.

 

[Stevan47]

Hi 'Newf': 5 Amp fuse is the maximum you need for the bilge pump, which is independent of all the other systems, so that even when the battery isolator is switched OFF, it will still cut in if the water level rises to a critical point (and providing the sensor is okay). I have the same setup in my vessel. After taking delivery from the dealer (it had been a demonstrator previously) I found a 15 Amp fuse in the holder. Way too much and a recipe for failure of the wiring harness. The factory specs and the wiring diagram all indicate 5 Amp. Hope that helps. Regards

 

[captstu]

I converted to a Rule switch after my original failed with some oil or soap on the sensor. make sure the pump goes low enough for the switch to turn off.


Stuart Bell
Ranger 25: Shearwater
(561) 352-1796

 

[Newf]

I took the advice of the folks who posted and reinstalled the pump with auto sensor. Also tied in a indicator light as Dan recommended. Now I know when it runs and for how long, which is nice to know. Thanks for all of the input.

 

[sheral]

Have you been checking the pump regularly and maybe throwing a bucket of some warm water with eco-friendly soap through it fairly often? We have dogs so it gets fouled with dog hair pretty quickly otherwise.

 

[Oceanwarryer]

I just installed a Rule automatic because of a similar issue (my Johnston was eating fuses, and as it turns out, was toast).

I took out the activator float switch. The Rule runs ever 30 seconds briefly - "testing" for water. If there is no resistance, it shuts off immediately. It pumps until dry if their is water, and I still have it on the switch as well.

It got a bit gummed up the other day, and I ran some dish washing detergent through it - problem solved.

 

[Newf]

I have started to flush the bilge more often and will pull the cartridge more frequently to check for crap. I use the boat for fishing mainly so lots of scales etc washed into the bilge and maybe too much to expect this little pump to handle at times. I have the indicator light in plain view so when running or trolling I now see when the pump is on. If it stays on for more than 10-15 secs then there is probably something wrong and I can pop out the fuse and check things out before it melts again. A cheap addition and for me its a bit of increased level of safety and comfort.

 

[sheral]

I would be more concerned if there were NO scales in the pump! :lol:

 

[Newf]

Ha Ha Good one,,,,It's been slow these last couple of months but should be pumping out more scales shortly.