Pump Replacement Questions

[ahd91]

Some of you may have seen another thread of mine in which I'm having terrible stalling/non starting issues. They've been infuriatingly intermittent, making diagnosis difficult.

Anyway, I managed to finally spot something amiss making me sure there's something up with the fuel pump. When the car was having one of its 'dos', I was turning the ignition to the second position to listen for the priming noise. Nothing was happening, so I went to the back, had a look at the pump and smacked it with a wrench. Lo and behold, it stuttered a couple of times in what seemed like an attempt to prime the system. Got the car started and then the whine of the pump would rise and fall as the car bounced about at idle.

So, on to the replacement. I have two main questions.

Firstly, has anyone else had any difficulty with the large black plastic ring that secures the unit at the top? I cannot for the life of me get it to turn - feels like it might have seized up a bit with gunk. Not even sure it's ever been off before. There's hardly any room to get any real purchase on it.

Secondly, about 10-15 minutes into the job, one of the disconnected fuel lines coughed up about 50-100ml of brown, sticky fuel. Is this returning from the filter or something, or should I be concerned?