MarkDTMcalib is absolutely right.
The diesel fuel also acts as a lubricant for the fuel pump and for the injectors (hence the need for leak back...). Running the pump with no fuel in it can be disastrous, therefore tow starting to overcome an airlock shouldn't be attempted.
All I did when I changed my filter was disconnect the push fit pipes and lift the complete filter body out from its cradle, change the (sludge coated!!!) filter and cleaned the filter bowl out, fitted the filter, and filled the filter casing with clean diesel, and put back together (not forgetting the two O rings!!) and installed it back into the car and reconnected the pipes.
Removed one of the leak back pipes and used a vacuum pump (use your mouth and spit out the fuel as a one off...) to suck the pipe leading down to the pump, air came out and then fuel... I quickly reconnected the leakback pipe and the car started straight back up. Ran ok for 5 seconds or so, hunted for a few seconds while the small amount of remaining air purged, and then ran perfectly.
If you need to slacken the injector unions to purge air out, make sure you reconnect the leak back pipes, even though it makes access to the 17mm injector nuts awkward. It won't purge with the leak back circuit open...
Good luck
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Topic: 2.2dti diesel primer (Read 3500 times)