The Thetford toilet flush pump did the all too familiar seized up rotor after a rather long 8 month layup since last use. It's done it before, and the usual extract pump, tweak rotor with a thin screwdriver got it working, and it'd been fine for years.
But this time the screwdriver tweak didn't seem to free it so well, it got it rotating OKish, but it was rather too stiff. It is the original pump, now 9 years old, and well used, so not too surprised if end of life, I figured this time I needed to fit the spare pump (kept in reserve, just in case, after last seizure) as likely water had ingressed and it's more than just a sticky seal this time, but being a frugal type, I thought I'd try to resurrect the old one before giving up on it.
I noticed that the rotor has 3 holes through it near the hub, effectively giving access to the shaft seal, so I squirted some WD40 SILICONE lubricant via the can nozzle tube through these holes. Let it soak a while, twiddled the rotor a bit, it felt much better, ran the motor, and low and behold it now runs freely and sweet as anything. No nasty graunchy sounds or feel suggesting serious water ingress and terminal internal corrosion, just a sweet free running pump again. Sure that the silicone lube has done no more than wick down a little between shaft and seal, and certainly hasn't 'lubed' the entire motor.
So hopeful that there's still life in the old pump yet, time will tell. And the 'spare' pump can return to it's spare parts hidey hole for however long before I need to consider putting into service!
And the spare pump is NOT £50 worth of Thetford's rip off prices sitting idle in the 'spare parts' locker, it's an identical Comet branded pump that cost me all of £16 when I bought it (now circa £19), so I don't feel too upset it isn't working for it's living..... yet.
Well done you Fiona, and Monty, for not only giving it a go, but for passing on realy useful info that I'm sure will be gleaned from your post for years to come, there are an awfully lot of Thetford toilet pumps out there, and yes, genuine Thetford prices are eye watering and are probably made in China anyway.
Dave.
------------- Never argue with an idiot, they will drag you down to their level and beat you on experience.
Mark Twain.
Ah, I take no credit: we had to change our pump because the screwdriver trick didn’t work & I didn’t know Monty’s silicone trick. I read the forum here plus YouTubes for that final confidence with the scalpel to open the lid for access. And this forum said it was ok to use other cheaper pumps - they all look the same to me!
So - thanks for the thanks, PickledOnion but they go to Monty & to everyone who chips in to try to help.
Quote: Originally posted by Pickled Onion on 25/7/2025
Well done you Fiona, and Monty, for not only giving it a go, but for passing on realy useful info that I'm sure will be gleaned from your post for years to come, there are an awfully lot of Thetford toilet pumps out there, and yes, genuine Thetford prices are eye watering and are probably made in China anyway.
Dave.
I'm a pretty shade of pink at the praise ... but thanks.
The Comet pump is IDENTICAL in every aspect to the Thetford one, with the exception of the branding info printed on the body. I'm in no doubt Thetford source the pump from Comet! .... and my Comet pump at least was made in Germany NOT China!
Only difference is that the Thetford spare pump comes with a PCB Edge connector fitted, whilst the Comet is bare wire ends. That's not a great obstacle, anyone who's got as far as extracted the faulty pump, should be capable of making suitable termination to the old pump's salvaged connector.
Not long back from a straight 25 day two centre caravan trip, and the revived pump was given 'a damned good thrashing' as the only toilet I used for the duration! Performed faultlessly, that must be over 150 'flushes', and it pumped on demand with a good flow every time!
When it first seized, and the usual rotor tweak only resulted in a rather too stiff and somewhat reluctant rotation, instead of the free running rotation it had done on previous 'resurrections', I thought the pump was a 'gonna' this time and replacement was called for. But have to say I was premature in my thoughts, a bit of silicone lube has proved that there is indeed life in the old pump yet.
For now at least, it's as good as it ever was, and the spare pump can rest easy in my spares stock as not yet needed to be called to action.
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Topic: Toilet pump resurrection
via mobile 24/7/2025 at 8:26pm
for not only giving it a go, but for passing on realy useful info that I'm sure will be gleaned from your post for years to come, there are an awfully lot of Thetford toilet pumps out there, and yes, genuine Thetford prices are eye watering and are probably made in China anyway.
... but thanks.
