Hello
Thanks for all the help folks. Got it working again. I think there was indeed a blockage elsewhere.
I used the hotwiring technique. That is a wonderful trick, so thanks for suggesting it.
I ran it through with one tube disconnected and running into a basin just to make sure the pump was pumping. It took a good few stop/starts (and plenty of tilting) but it eventually kicked in. I then just connected it back up and away it went. I ran it for a good hour or two to try and get all the air bubbles out (tapping the tubes with a screwdriver).
Thanks for all the help folks. Got it working again. I think there was indeed a blockage elsewhere.
I used the hotwiring technique. That is a wonderful trick, so thanks for suggesting it.
I ran it through with one tube disconnected and running into a basin just to make sure the pump was pumping. It took a good few stop/starts (and plenty of tilting) but it eventually kicked in. I then just connected it back up and away it went. I ran it for a good hour or two to try and get all the air bubbles out (tapping the tubes with a screwdriver).