Erratic Shower sump pump

[nikvah]

Hi there,

I would really appreciate any advice on the cause of my erratic shower drain pump. I do not know what make it is as it's label faces under the bath altough I do know it's a 12v pump (possibly type: F3B-19) and has 15A fuses.

 

It is fine when we're charging from the mains and when we're underway and usually turning the engine on will get it going (but not always). After a full days cruising or battery charging by the 2x100w solar panels it is very temperamental and inconsistent even when inverter displays fully charged or batteries on float.

 

I've tried recording the displayed battery bank voltage when it works and when it doesn't but this has varied from 14.6 - 12.7 in both cases.

 

The batteries seem fairly healthy and retain there charge well but I will replace them if this is a common symptom of failing batteries otherwise perhaps a 240v pump would be more reliable.

 

[David Mack]

It could be a problem with the pump wiring. Try checking the voltage at the pump connections, not just at the battery.

[Drayke]

If the electrics are fine then try changing pump for a Whale Gulper shower drain pump, brilliant pumps. I would not go down the 240v route.

[Tiggs]

Johnson Fb3-19?

 

An impeller pump.

 

If voltage at the pump is OK; probably got stuff stuck in the impeller.

 

Take it out, take the impeller case to bits and clean it out.

 

Re-assemble, possibly with new impeller.

 

Having said that Whale Gulpers are best for shower drains, as F Drayke says.

 

 

Oh, and no way would I put 240V under a shower.

Edited July 11, 2016 by Tiggs

[ditchcrawler]

How old is the pump, does it have a filter, have you cleaned the filter or pump?

[Tony Brooks]

It could be a problem with the pump wiring. Try checking the voltage at the pump connections, not just at the battery.

 

I agree, especially a loose/dirty connection somewhere but to get a meaningful result you need the pump turned on and trying to work. If the pump is turned off even with a truly awful connection you are likely to measure battery voltage. A test lamp with a 21 watt bulb may do a better job.

 

It could also be a faulty switch so lots of checking to do.

Edited July 12, 2016 by Tony Brooks

[nikvah]

Thanks alot for all the useful suggestions. It is a Johnson impeller pump as it matches the images on their website, I assume it is same old as the boat (13yrs) so I will set to cleaning the filter. The electric connections may be trickier as I didn't mention that if it decides not to go it trips the trip-switch.

Cheers All

[frahkn]

Hi there,

I would really appreciate any advice on the cause of my erratic shower drain pump. I do not know what make it is as it's label faces under the bath altough I do know it's a 12v pump (possibly type: F3B-19) and has 15A fuses.

 

It is fine when we're charging from the mains and when we're underway and usually turning the engine on will get it going (but not always). After a full days cruising or battery charging by the 2x100w solar panels it is very temperamental and inconsistent even when inverter displays fully charged or batteries on float.

 

I've tried recording the displayed battery bank voltage when it works and when it doesn't but this has varied from 14.6 - 12.7 in both cases.

 

The batteries seem fairly healthy and retain there charge well but I will replace them if this is a common symptom of failing batteries otherwise perhaps a 240v pump would be more reliable.

When I bought the boat, I was very doubtful about the shower pump and bought an replacement ready for its inevitable failure.

 

We tend to shower at the end of the day and leave the engine running until we have done so (our batteries need replacement). So far, the new pump is still in its box.

 

Frank.

[BruceinSanity]

Thanks alot for all the useful suggestions. It is a Johnson impeller pump as it matches the images on their website, I assume it is same old as the boat (13yrs) so I will set to cleaning the filter. The electric connections may be trickier as I didn't mention that if it decides not to go it trips the trip-switch.

Cheers All

Almost certainly a failed/blocked impeller, then. The stall current of the motor is tripping the breaker. As others have said, get a Gulper.

[ditchcrawler]

Almost certainly a failed/blocked impeller, then. The stall current of the motor is tripping the breaker. As others have said, get a Gulper.

What would be the load of a Gulper compared to the Johnson? Just thinking about the trip and wiring

[BruceinSanity]

What would be the load of a Gulper compared to the Johnson? Just thinking about the trip and wiring

 

Doubt if there's much difference, but a quick check of the specs should sort it.

[tagulablue]

similar problem with my shower...over past few years the fuse as blown on the 1st use of the season.. quick change of fuse.. been off boat for 2 months come to us shower today and the fuse as blown again. Replace fuse and it blew straight again ..no effort on part of the pump to start. Tried again and same thing happened. Is there anything else that is easy to check... my ability is limited to hitting something with a hammer /changing a fuse or calling an engineer.

[WotEver]

... my ability is limited to hitting something with a hammer /changing a fuse or calling an engineer.

Well you've already tried the fuse solution. So hit it (the pump) gently with a hammer. If that fails then you're down to the third option.

[tagulablue]

Well you've already tried the fuse solution. So hit it (the pump) gently with a hammer. If that fails then you're down to the third option.

I knew the hammer would come in useful one day...I'll try that thank you

[Tony Brooks]

Please NO. The motor is likely to have permanent magnet fields and if you hit it with a hammer you may shatter them. That will ensure the fuses always blow.

 

By all means give it some GBH but please use the eel of a slipper or ordinary shoe.

[BruceinSanity]

Once again, we need to know what kind of pump. If it's an impeller type (Johnson, Water Puppy and similar) then it's probably a failed impeller. If it's a Gulper, probably a power supply issue.

[nikvah]

I used up my small supply of 15A fuses trying to check the connections to the pump with it trying to work and resorted to 20A fuse at least it only tripped the breaker switch each time. Anyway, it was not the connections so checked impeller which was not blocked and resorted to option 4 (omitting 2: hammer) and took it to a boatyard where the engineer quickly spotted that although the impeller was OK it was the wrong one for that model. Some other bodger had replaced it during it's 5 year life under the bath.

Sorted now (tho' somewhat poorer) but at least I don't need a new battery bank.

Thanks again for the help.

[WotEver]

Please NO. The motor is likely to have permanent magnet fields and if you hit it with a hammer you may shatter them. That will ensure the fuses always blow.

 

By all means give it some GBH but please use the eel of a slipper or ordinary shoe.

 

Well, I did say 'gently'

[ditchcrawler]

Please NO. The motor is likely to have permanent magnet fields and if you hit it with a hammer you may shatter them. That will ensure the fuses always blow.

 

By all means give it some GBH but please use the eel of a slipper or ordinary shoe.

I think I read that in a magazine somewhere for fixing a water pump

[Tony Brooks]

Yes, and I can probably name the magazine

[FadeToScarlet]

Yes, and I can probably name the magazine

Probably Waterways World, their technical writers are brilliant

[Tony Brooks]

Probably Waterways World, their technical writers are brilliant

 

That will please Nick and Martin no end