Hi Will,
It looks like these "steam engine" machines are starting to raise their ugly heads. They are so annoying especially, maybe like you, I got it for my small kitchen not a tucked away utility room or garage and the noise resonated round the whole house.
I will try and describe the pumps as best I can, though I am no engineer and it may not make huge sense.
My machine made exactly the same noise with its pump that you describe. The 2nd engineer who called showed me the two pumps. The one in my machine did not have a little blue cover on one of the outlet valves. I believe the engineer described it as the valve that stops water going back into your machine if you have fitted your machine beside your sink and your own dirty sink water made its way down the outlet tube for your machine. This happens apparently if you don't have a the outlet tube high up enough. Mine isn't under my sink however he said it is a percaution incase it had been.
The 2nd pump he put in did have the blue "cap" like thing on this valve and now the machine makes no such pumping noise anymore. I have done 3 washes since and so far so good.
I hope you have success with this. The first engineer who called didn't seem to know anything about the "blue" lid and didn't even take the pump out. He said the steam engine noise was normal and I had to live with it. The 2nd engineer seemed to know and care more and was very helpful. Persistant with Hotpoint seems to be the key as I had 2 rounds of complaining with success at the end of the 2nd round.
Besy wishes
Fiona
Fiona 12
October 2010