Pumpout Kills Prime

[Codacap]

We have a standard Jabsco electric toilet. Works just fine. Returned from a short trip and did a pumpout. Now we cannot get the toilet to prime the intake flow. Normally there is a good even flow of intake raw water. Now there is none. Any ideas?

[Hannah on 'Rita T']

Pour water into the head and pump.

[Blue Stocking]

Originally Posted by Hannah on 'Rita T'

Pour water into the head and pump.

--and your finger over the intake anti-syphon valve opening.

[HopCar]

That's strange. The intake pump is a completely separate system from the discharge side. Pouring water into the bowl shouldn't have any effect on the intake pump. An air leak on the intake side could cause this. As previously suggested check the anti-syphon valve first. A bad impeller in the pump could cause this as well. Is the intake line blocked? Check your strainer. Did you close the intake seacock by accident? I just don't see how it could be related to having the tank pumped.
Peggy Hall where are you? This ones got me stumped!
Buy Peggy Hall's book!

[zeehag]

mine did that regularly--it did help to continuously pump into the bowl sea water as the pumpout was being done. pumping in the water in as the tank was pumped out also kept the tank cleaner than just pumping out.

[Codacap]

To all who replied, many thanks.

I resolved the issue this morning in about 15 minutes.

For others here is what I did.
1. Close intake seacock
2. Remove intake hose from seacock.
3. Remove intake hose from rear of toilet
4. Fill the hose with water and run the electric motor. Hold the hose over the bowl. This causes the water to be discharged from the hose and clears the air lock.
5. Reconnect hose, open seacock and use normally.

But I still don't know why a pump-out caused this. Yes, a note to Peggy would be good to do, but I thought she was out of the business.

Now where was I....ah yes, cleaning the waterline.

[HopCar]

George,
It sounds like the impeller or the impeller housing is getting a little worn.
Those Jabscos are pretty good at clearing air when everything is working right. If it happens again open it up and see what's going on. I say that like it's easy. I actually hate working on those toilets. I don't know how many times I've sold someone a replacement motor only to have the person return the motor and buy a whole new pump assembly just to avoid taking the darn thing apart.
Enjoy cleaning the waterline!

[peghall]

Originally Posted by Blue Stocking

--and your finger over the intake anti-syphon valve opening.

That would ONLY be necessary if the loop is in the wrong place and/or missing its air valve. Intake vented loops in manual toilets and also most electric macerating toilets should NOT be installed in the line between the thru-hull and the pump. They belong between the pump and the bowl (yes, you'd have to replace the short piece of hose the toilet mfr uses to connect 'em)...see the drawings in the installation instructions for every manual toilet. The air valve that's SUPPOSED to be installed in the nipple, will prevent any squirting.

But the new all china electric "thrones" don't have a connecting line between the pump and the bowl...so the line between the thru-hull and the pump is the only place the vented loop can go. In that case, it's necessary to install an electric solenoid valve that's wired to the flush button. Pushing the button closes the valve so that the toilet can prime...let's it open again to break the siphon when the flush button is released.

[peghall]

Hi George...I don't sell anything any more, but I am still very active.

There's no way that pumping out the tank could have anything to do with a toilet's ability to bring in flush water...so the timing was just coincidental.

I'm guessing you have a seriously worn intake impeller. That can simply happen over time because every time you flush it, it has to run dry for just a second or two till it primes...flushing when the intake thru-hull is closed will inflict a LOT of dry friction heat damage. Unless the impeller is truly "fried" or a vane is cracked, you won't see the wear with the naked eye because it's so even...but as the edges of the vanes are worn down, the impeller becomes less and less able to pull anything through it. So my advice: rebuild the toilet or replace it...'cuz if the intake impeller is worn, so is the discharge impeller.

[Codacap]

Peggy,
Impeller was new this past May. I will check it. I don't get it, but the fix worked and the flow is as strong as usual.

[peghall]

Unless it's really "fried" or a vane is cracked, you won't be able tell anything just by looking at it 'cuz the vanes wear evenly...and there's only a fraction of a milimeter between an impeller that's working to spec and one that can't move anything through it at all. So since you'd have to take the whole pump apart to see nothing, don't waste the effort.

Have you tried to keep skanky sea water out of it by flushing with the intake thru-hull closed and just adding water to the bowl? 'Cuz that'll destroy an intake impeller.

And finally...the impeller is new...how old is the toilet? The impeller HOUSING could be scratched and worn enough to interfere with the pump's ability to prime.

It's working ok now, so it may have just been a fluke. Let's see what it does with the first flush after the boat has sat a while.