Vauxhall Astravan engine making tapping noise

I've just put a second hand engine in my 2001 Vauxhall Astravan. From what I can tell, the engine was good and the only thing that needed changing was the fuel pump. However, I started it up and it is making a loud knocking/tapping noise from the top end of engine. Any ideas what this could be?

Asked on 27 August 2013 by funkypunk

Answered by Honest John
Might be an airlock between the fuel pump and the injector rail.
Similar questions
How are you able to tell if a turbo is not working on a Volkswagen caddy 1.9 diesel? My van is losing power and smoking when I rev the engine. It also wants to stall when I try to pull away.
I own a Vauxhall Viviro 1.9 CTDi (2005 model). Can you tell me why the glow plug light is stuck on and the van is losing power?
I had the head gasket on my Peugeot Boxer changed, but on the way home (after about five miles) it decided to lose power and cut out. No lights came on the dashboard, it just went dead. After a couple...

Value my van