BMC 2.2 Sometimes difficult to start.

[Quattrodave]

Morning all,

 

BMC 2.2 diesel engine, over the last few months its not started on a number of occasions.  From cold I give it a bit of throttle, hold the heayer plugs for 10 to 15 seconds, press the start button, she turns ove and bursts into life, runs for about 8 seconds revs pick up slightly and dies.... The only way I've found to get ut started know is to crck off each injector, put some paper towel under each one and crank until fuel appears on each injector.  Nip the injectors back up, and crank after a good fee seconds she'll burst into life... The old gal will run fine for the rest if the day...

 

My assumption here is that some how air is getting into the fuel line, problem is where...! I've been all over the pump, pipe work and filter but can see any dampness. My only thought now is the mechanical pump.... Any ideas..???

 

Thanks

 

Dave.

 

Edit:

I had the injection pump and injectors serviced a few years ago by a reputable diesel shop.

Edited July 27, 2022 by Quattrodave

[john.k]

You are corrrect,an air leak into the fuel system,which will need to eliminated.

[Tracy D'arth]

Use a separate gravity fed tank into the injection pump. If it then runs well the air is getting in before  the injection pump.

 

If its better,  feed the extra tank into the lift pump. If it still does it, its the lift pump. Its not uncommon for a crack in the diaphragm to let air in and most importantly fuel into the sump. Has the oil level risen at all?

 

Otherwise its down to pipes and unions  or fuel filters letting air in on the suction side of the lift pump.

Edited July 27, 2022 by Tracy D'arth

[David Mack]

2 hours ago, Quattrodave said:

My assumption here is that some how air is getting into the fuel line, problem is where...! I've been all over the pump, pipe work and filter but can see any dampness. My only thought now is the mechanical pump.... Any ideas..???

If its sucking air in, but not leaking diesel out, you won't see any dampness. Have you checked your fuel lines to confirm that the injector leak-off line goes back to the tank, and not just to the fuel filter?

[Quattrodave]

47 minutes ago, Tracy D'arth said:

Use a separate gravity fed tank into the injection pump.

 

Has the oil level risen at all?

Could be time consuming, it doesn't always do it...

 

Good call, I will check!

48 minutes ago, David Mack said:

Have you checked your fuel lines to confirm that the injector leak-off line goes back to the tank, and not just to the fuel filter?

Injector leak off goes to the top of the filter then on to the tank.

[Quattrodave]

I dropped a new fuel pump on this weekend, bled the fuel system again and ran it for 40 mins...  We'll see how it behaves over the next few weeks...

[Bee]

Changed the filter on my Beta a while ago since then it does the same, have replaced washers, 'O' rings every damn thing and it still does it, little leaks can be really. really hard to find.