Diesel - Fuel system Tips and Tricks
Air in fuel supply and tips on bleeding
Grenjs: Having had the injector pipes off to do the glow-plugs, I've loosened the pipe-to-injector union to allow bleeding, then cranked and cranked and it just won't start. Any suggestions?
Rob: Just check the fuel-cut off solenoid wire is back on
HarryMann: Loosen all 4 unions and see...
Then if no joy, try removing the return hose from the pump, putting a hose on here and sucking some fuel through..
Pump should be self-priming... in theory. The injectors should actually be self-bleeding but the pump can often fail to lift and self-rpime fully, due to trapped air, so try sucking it through.
Grenjs: Success, thanks! Took the return pipe off (despite there was fuel in the pipe) and sucked like billyo. Took quite some serious suck to pull the fuel through, but it did eventually. Put the pipe back on. Cranked the engine and it started on the 3rd or 4th crank.
If you roam the scrapyards and come across any Peugeot diesels, you'll find they nearly all have a rubber priming-bulb in the main fuel line to the inj.pump. Just cut it off outboard of all the clipped joints, leaving as much pipe and bits and bobs as possible for later use....
These are connected with nice little stainless pipe clips (removable and refittable with pliers, [i]very clever clips[/i])
Using suitable hose sizes, this can be fitted in your main fuel-line from the filter... and assist in these situations, forcing fuel up through the pump and out the by-pass, helping to clear any air.
I think it is the injectors that are meant to be self-bleeding and not always the pump.
NB. Andy Simpson has pointed out that on these installations it's the by-pass return joint on the top of these filters that is usually the culprit if air continually gets into main fuel-feed line to the pump. I believe he calls it the $%£^&^ fuel-filter from hell!