Well haveing waxed lyrical about my Klargester having run for four years with absolutely no attentiona whatsoever, last week I was walking up the garden and a small whiff alerted me to the fact it wasn't doing its job.
Opened her up, and by golly the wheel had stopped turning..
The pulley had fallen off the motor shaft and was somewhere at the bottom of the tank.
A quick call to local agents and 2 days later the sludge tanker calls and empties it, recovering the pulley by carefully NOT sucking it up.
A couple of hours later a man in a van calls, and aa quick removal of te woodruff key from a scrap motor he has on board, a whack with a hammer (he tried to convince me the pulley wouldn't go,and needed replacing.. but I've seen woodruff keys before) and a general tighten down all over and a bit of a hosedown of the disc to make him up to the miniumum hour service, and the biodisc is humming away nicely. Belt still in first rate condition after 4 years. Should do ten or so at a 20 quid replacement cost.
Total cost for emptying (75 quid ) and service (about 20 quid) was with vat about 110 quid.
He did say that 'self installed ones - people don't double check the tighteness of the grub screw on the pulley' and he may well be right.
So all in all if its only going to cost me about 25 quid a year on average, its quids in versus mains drains which I couldn't have anyway.
It actually was nowhere near full up of sludge either. I reckon an annual empty is absolute worst case frankly.
I'll provably do it again in 2008/9