Submersible sewerage pump impeller stuck

dr.fuzzenstein

I have a waste water system at home, part of which has an Ebara submersible pump in it.
The pump is only turning very slowly and will trip the fuse after a while, when I turn it by hand it is hard to turn.
I am currently in the process of disassembling the pump to see if there's maybe something jammed or if the motor needs new brushes.
Here's my problem:
I need to remove the impeller from the pump.
I have looked at it for the best part of a day and I cannot work out how this is done.
If you apply a wrench to the nut at the end of the impeller, you have no way of immobilising the impeller or the shaft it sits on.
I have tried this every which way.
I checked the manual, it simply says "remove impeller", not very funny and even less helpful.

So, in short, my question is:
Has anyone here any idea how I get the impeller off the shaft on an Ebara CF4 90 01 440 submersible stainless steel pump?

Buford T Justice

I've worked on Tsunami submersibles before, and the first thing to do is make sure the nut isn't a reverse thread nut.

The impellors are generally made from rubber, and if so then try to grab it with a grips or something. Shove a screwdriver in between the blades to jam it.

It always worked for me, and I've repaired some fairly shitty ones in a hire shop previously.

Give the nut a dose of penetrating oil and leave it soaking overnight before you tackle it.

Edit: This won't necessarily give you access to the armature and the coil though, the motor will be sealed in the housing. There won't be brushes in this motor though, as its not vented.

I'd be willing to bet that there is some stringy stuff behind the impellor causing the jam, or the oil seals have bitten it, and let water in and knackered it out.

dr.fuzzenstein

Will do, I'm working along those lines.
The only thing I can possibly grab is the impeller itself which is metal.
I have already bent two of the blades by trying to grip it with a pliers or wedge a screwdriver in there.
I don't believe that someone would build a pump where you'd have to practically destroy the impeller in order to get the nut off, because the kind of force required to get the nut loose would certainly do that.
And even funnier:
To get a new impeller on, you'd have to either only put the nut on very loose, or destroy the new one as well.
It's electric and made in Italy, who bought that?
Italians are not famous for their electrical engineering, or only for the wrong reasons.:)
Have a feeling that fixing this pump might well destroy it in the process...
Any suggestions for a good replacement? Possibly German or from any other nation that has mastered electrics and engineering.

Buford T Justice

Tsunami are excellent, but consequently not cheap.

Is it not possible to grab the shaft behind the impeller?

Edit, that name might be Tsurumi either.

dr.fuzzenstein

Fingers McGee wrote: »

Tsunami are excellent, but consequently not cheap.

Is it not possible to grab the shaft behind the impeller?

Edit, that name might be Tsurumi either.

No the impeller sits only a fraction of a millimetre away from the housing.
Also, there is a cowl that surrounds the impeller.
With the cowl in place the impeller can't be grabbed properly and won't come off and without the impeller removed the cowl won't come off.
I was wrong about the Italians, in this case they have designed something that, once put together, cannot be taken apart without totally destroying it, which is quite possibly the design of an (evil and insane) genius. :mad:
Will buy a good pump this time (I didn't buy the first one), it's just another bill I don't need, so will try to coax this baby back to life.

Buford T Justice

Get a belt or a leather strap and wrap it tightly around the impeller and clamp it tightly in a vice. This should give you a tight grip to start with when trying to remove the bold.

You may well need a bearing pullers to get the impeller off too.

dr.fuzzenstein

Fingers McGee wrote: »

Get a belt or a leather strap and wrap it tightly around the impeller and clamp it tightly in a vice. This should give you a tight grip to start with when trying to remove the bold.

You may well need a bearing pullers to get the impeller off too.

Well I actually got it off.
The impeller is hard to reach because it sits inside a cowl, getting anything around the edge of it is a non starter.
In the end I had to jam a screwdriver into the opening for the outlet pipe and through the impeller.
While holding the screwdriver in one hand I then applied force with a wrench with the other and finally the nut came off, though not after bending some impeller blades out of shape.
Once the whole impeller was off I tried to see if there's any clever way of securing the shaft to unscrew the impeller, there isn't.
Jamming a screwdriver into the blades is the only way I can see, unless the manufacturer has designed some very spacey and exotic looking specialised grappler tool that will cost hundreds to do one job and nothing else.
It is the most brainless, idiotic design I've ever seen in many years of screwing around with electronics, cars, computers and any other mechanical contrivance you can imagine.
In the end I had it all back together again, pump still slow, let it run in the dry for a bit, speeded up, speeded up, bit by bit, till it just whirred back into life.
So it stopped for no good reason that I could see and now runs again for the same reason, like everything else that breaks in my life.
But no matter, I'm happy for as long as it runs, maybe it's on it's last legs but if I get a bit more out of it I'll be happy.
Thanks for the help, it is much appreciated and should it go wrong again I won't be buying an Ebara pump.

Buford T Justice

Maybe the bearings in the armature are giving out....

dr.fuzzenstein

Fingers McGee wrote: »

Maybe the bearings in the armature are giving out....

Possibly. I don't know if there's a fix or if it's worth it.
Will check out prices for Tsurumi.

Buford T Justice

If the machine can be broken down into its component parts, then you should be able to source the bearings and related water seals for it. Any good engineering supplier should have the bearings.

dr.fuzzenstein

Thanks, will try.