Hard start, smoke, then knocks, then fine?

[bruce1966us]

sounds like glow plugs or low compression

 

[guyd]

the glow plugs are all new - and all connected via a bus bar - im not sure how it cant work - the low compression suggestion is probably the most likely.

 

[Domush]

If you are starting it in 50F temps, I can't see how glow plugs are even needed. I use a bobcat with glow plugs which starts in 40F weather within 2 seconds without even touching the glow plugs.

I'm voting for low compression as well. Maybe valves not seating well/worn out?

 

[guyd]

after a good 'italian tuneup' = thrash the **** out of it, plus tightening the #3 injector up might help....

 

[gengine]

If you run your glow plugs, it's heating the cylinder. Opening the de-compression valve, spinning the motor for a while before letting go is going to suck in a lot of cold air, making the glow plugs almost useless. Verify your glow plugs are getting power while cranking, if they are supposed to like I think I read. The blueish white smoke is cold unburnt fuel. I don't think things are getting heated up enough. Compression may be a culprit as well. Air being sucked into a fuel line will make the engine knock, if you have fuel leaking out, then there is a chance you have air leaking in.