BC26 (and possibly other boats) ballast pump problem

[Nick Orchard]

I normally leave my boat without ballast in so that it sits higher in the water and keeps the white line cleaner, so I possibly use the pump more that others. When I came to empty the tanks after my first sail of the season a couple of weeks ago, I switched the pump on and was surprised by the complete absence of any noise. Tried switching everything off and on again as you do, but still nothing. Assumed that it must be the pump electrical connectors corroding over winter, but no, they were fine. Took the whole pump off and removed the impeller and found that I couldn’t turn the motor shaft, even using pliers to grip it.
Took the whole thing home and stripped it down to be met with quite a mess inside. Top bearing rusty brown and completely seized, bottom bearing just about moving but not good, thermal cutout switch open-circuit and the interference suppression capacitor wandering around loose because both terminal legs had corroded through completely!
On consulting the manual I noticed that it advises that the unit should be mounted with the pump head below the motor, whereas in my 26 it has been installed the other way up. This means that when the shaft seals loose their effectiveness then salt water will start leaking from the bottom of the pump, down the shaft and into the motor, hence the damage. In hindsight this appears rather obvious, so when I put it back I’ll be mounting it the other way up, which will probably require a mod to the plumbing, and possibly a reversal of the pump direction (it pumps both ways).
This post is therefore an advisory to everyone with a ballast pump to check which way up it’s been installed, and to turn it round if the pump head is currently above the motor.

[Willie The Rut Lander]

Nick
Thanks for the advice. I have a Whale Pump on my BRe - what make is yours?
Additionally, I'm looking for advice as I'm thinking of hard-wiring my pump into the ballast tank and routing the cable through the starboard locker and to the control panel in the cabin. I will switch the pump on from the control panel, perhaps with an extra switch to ensure it's not turned on in error, and will then just extend the outflow pipe out through the main ballast hatch as required.
I am thinking of using Scanstrut seals between locker and tank, though these seals are designed for vertical cable seals. For 99% of its life, the tanks are empty as the BRe lives on a trailer.
Does anyone think this is a good or bad idea and have any suggestions.
If it doesn't work I can always simply refill the small holes.
Thanks
Willie

[Nick Orchard]

Willie - the BC26 pump is a Johnson FB4-19 model 10-24689-01 to be precise (well it is on my boat). It's probably rather OTT for a BRe as it pumps 45l/min and draws 10-12A, but we have 750l of ballast to dump. Attached is a photo of most of it mounted the wrong way up in my locker. The 26 also has a relatively complicated plumbing arrangement where the pump can be switched between ballast or bilge, and you can use either electric or manual pump.

Regarding wiring, on the 26 it is cabled via the bulkheads to the main switch/fuse panel which is where it is operated from, much as I think you're suggesting on your BRe. Can't give you any advice on what would be ok or not on a BRe I'm afraid.

[RogerLennard]

I go for a relatively simple solution that doesn't involve switch panels, extra wiring and drilling holes in my BR20. The pump is kept dry until I put it in the bilge. Check out the video at around 7 minutes.

https://youtu.be/YqqhbnS7yBU?si=cbyE3995_CebsPBr

[AndyB]

Hi Nick,

I have exactly the same setup so I guess this is a standard installation. Thought it would be easy to turn it around but not so sure now.

Seeing my boat is still non-sailable it would be great if you could let us all know how you changed it and I will copy.

Thanks
Andy

[Nick Orchard]

Well the pump is all back together again now, and reinstalled on the boat yesterday. Turning it the other way up was slightly more involved than it should be on other boats as I have my fridge compressor mounted on the bulkhead and it gets in the way of the inlet hose. Without the compressor in the way you should be able to just turn it 180 degrees upside down and screw it back in the same holes. I had to glue another pad on a bit higher up, and it's also angled to give a better run for the hoses - see photo. When you turn it the other way up you will need to change the direction of pumping. You can either just switch the 12v wires round so the motor runs the other way, or you can turn the pump head 180 degrees. Switching the wires might sound easier, particularly as you may need to add more wire with the motor being further away, but it could cause confusion in future with the black supply wire connected to the red motor wire. Turning the pump head is just a matter of removing two nuts, turning it round and putting it back on again, so pretty simple.
One thing that I've noticed over time is that the system leaks air, so I have to prime the pump using the hand pump first otherwise it fails to suck the water up high enough to get to the pump. I think some air is getting in via the ballast/bilge changeover valve as you can see bubbles in the pipe, and also air is being drawn backwards through the Whale hand pump, and this is in spite of me installing a non-return valve in the line. Once it's sucking water it's ok, but it still slowly sucks the water back from the hand pump until after about 5 minutes it's just sucking air again and needs another few pumps on the handle. It takes about 20-25 minutes to empty the tank, but I seem to remember when new it took 15-20. 
If you want any info about refurbishing the motor then let me know.

(For some reason the thumbnail photo is rotated 90 but it's the right way up when you click on it for full size?)

[Sea Simon]

Imho...Given that this pumps duty is to empty a ballast tank (and so, it's planned to run it dry at some point?), I'm  not surprised that this type of flexible lobe pump is starting to struggle as it ages. Never mind the inverted fitment causing sealing issues too!

These pumps depend almost entirely on the flexibility of the vane materials to operate, although casings will wear if pumping gritty/sandy water. I was astounded how much sand came in with the water ballast on my BRe, particularly when I  inadvertently left the fill/drain plug out while moored over sand for a few tides. So much sand that I  needed to actively flush the tank with a hose, while the boat was on a concrete slipway. Not that the Bre had a pump to fret about, but sand is HEAVY!
All vanes also need to be intact. If a vane is shed, try to find it!
These pumps are known to have relatively low suction capabilities.

Try fitting a new impeller? Apparently there are two different materials used, nitrile rubber or polyurethane. The polyurethane  impeller being preferred for self priming duty.

Copy parts are cheap enough (buy several, you'll need them if you plan to run it dry), they are imho acceptable for this non critical  duty (although I wouldn't fit some of these knock-offs to the similar pumps fitted for diesel engine critical cooling systems),   and they are easily fitted with simple tools.
An occasional dob of silicon grease (or Johnson pump lube - glycerine) thru that brass plug on the suction port might help lengthen service life?

Try and seal the suction line that is drawing air.

Perhaps fit a foot valve to the suction line, to try to keep fluid in the pump after it stops. The Whale bilge suction strainers can come with a foot (non return) valve incorporated.

[AndyB]

Thanks for the advice Nick.

I have the same problem with the pump needing priming. I have only done this once but it is a shock the first time.