Hello, new to the forum. Just rebuilt the engine in my XF, due to it knocking No1big end out and spinning three of the mains. All back together and refitted now. My issue is, how do you bleed the diesel from the filter through the HP pump to the fuel rails and injectors? I don't want to crank it, because of damaging the 'dry' HP pump. Any help would be very welcome.

Thanks, Phil.

 

To bleed the low pressure side, you just need to cycle the ignition on and off. Topix states do this 4 times, but even when replacing the fuel filter this doesn't work. I usually do it about 10 times.


Ignition on for 10 seconds, then off, do it about 10 times. This will energise the low pressure pump up to the filter. After 10 times or so of ignition on and off, this should fill the filter. Try cranking, may take a few attempts. Once started, you'll need to let it run for a few minutes to complete bleeding procedure.

 

Thanks, but my issue is the bleeding of the 'dry' high pressure side of the fuel system. When I say 'dry', I mean all pipework is empty of fuel because I've just completely rebuilt the engine (had to change the block because of spun main bearings). There must be a recognised method of refuelling the fuel system, just hope someone can tell me.

 

I understand - however I've replaced a few engines ( 3.0LD ) which is basically the same set up. I have also had to replace the HP pumps under warranty, which states that any connecting pipes that are loosened for any reason, must be replaced. So in a sense its dry. You just need to bleed the low pressure side up to filter. I mention doing 10 times because this will help fill the filter, and it should start within first or second try of cranking. I've done this many times and never had an issue with the HP pump failing because of having to change components.


On the Land Rovers - they have a tool they put in place to manually bleed it, but again, its on low side, not high side. High side has to produce 150 bar ( 2,000+ psi ) to even start. You're going to need to crank it no matter what.

 

Thanks for that info. I had cycled the low pressure side about 10 tines (I let the pump run for 15 seconds then rest for30), then cranked it with No1 and No2 injector pipes cracked, to stop the air in the rails from causing any air lock issues in the HP pump. Nothing. I've cranked it twice, but didn't want to push my luck turning the dry pump.
I'll give it another go tomorrow and let you know (fingers crossed).
Phil.

 

Hi, im interested to know the outcome, (what you did to get the fuel through to the pipes. I'm having pretty much the same problem on the 2.7. The pipes are bone dry. I have fuel up to the pump but, nothing going to the rail?