you may remember this post of mine:

Message 1 in thread From: Suz ( snipped-for-privacy@dontsendmail.com) Subject: Help! the CH pump is trying to make a bid for freedom.
View this article only Newsgroups: uk.d-i-y Date: 2003-11-24 15:46:47 PST
Our radiator suddenly started to rock 10 minutes ago (all over the house) and hubby tracked it down to the pump (HE thinks). His description is the pump is making the same noise as the radiators - rattling. The boiler seems OK.
We have switched it off, but with -1 predicated for tonight we'll need it in the morning. Any ideas what might be wrong and is it safe to use? Or will the pump wrench off its fittings, grow legs and scamper off into the sunset?
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Well if it hasn't started again tonight and it already -1 !! Sod law isn't it? Hubby's out in his slippers in the boiler house now, starting and stopping something and tapping things. If it weren't broke, it soon will be. Can't believe our rotten luck.
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You probably need a new pump. My last one went like this, probably because several impellor blades have broken off. I wouldn't use it. Pumps are real easy to replace (if the pump valves work...) and cost from around 30 quid for a cheapie.
You just turn off the electricity. Turn off the pump valves. Disconnect old pump cable. Undo the pump unions. Remove old pump. Insert new pump. Redo the unions. Connect new cable. Turn on the valves. Turn on the electricity.
If the pump valves don't turn off, then additionally you turn off the water supply (if a header tank type system) and drain down instead. Don't forget to add inhibitor when you refill. Take the opportunity to replace the pump valves.
Christian.
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Christian McArdle wrote:

I fitted a new pump for my daughter last Sunday. My procedure was almost exactly as above except for the 'remove old pump' bit. Instead, it was as follows: Heave with all my strength with a large Stillson wrench, with my daughter's boy friend holding the pump to prevent other pipework from rotating no success. Apply penetrating oil to both fittings & have a cup of tea. Repeat procedure, with me holding the pump, again without success. Use hot air gun on both joints, with more penetrating oil. Eventually managed to slacken the fittings after 1 1/2 hours. Fortunately the remainder of the job went well and their heating is now working again.
Terry D.
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On Tue, 27 Jan 2004 12:25:59 +0000, Terry D wrote:

The harder you try the heard they stay put! The rings on the couplers are relatively flexable and so if you let them know whose boss they simply grip onto the pump threads all the harder.
The best tool is a pair of good quality pump pliers.
--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at www.diyfaq.org.uk
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--
Andrew

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I had to cut mine off through corrosion. New valves fitted with plenty of PTFE on the threads - hoping this will prevent it.
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*You're just jealous because the voices only talk to me *

Dave Plowman snipped-for-privacy@argonet.co.uk London SW 12
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