Problem with starting the engine

[marioxp]

I had a problem with starting the engine (Volvopenta MD 2030). 
Sometimes it starts very hard, sometimes it starts right away.  When it works, it works beautifully.  I can't figure out why it sometimes starts so hard, even when hot it starts hard, even when cold it starts right up. 

I didn't notice any smoke from the exhaust.   

Does anyone have an idea what the problem could be.

[Happysailor]

You first would say, with an diesel engine you have a hard start cold (e.g. fuel starvation, poor filled filters due to air locks) and a good start when hot.
Thinking about potential lack of compression when hot, e.g. valve clearance too large due to wear when hot.

Any other ideas?

[Odysseus]

2 things.
1....the 2030 has a relay (black box by the exhorst  outlet) for the glow plugs, its notorious for failure,  but not completely,  I would change it.

2.. next test the glow plugs for continuity,  should be around .9 ohms if I remember.

I always carry spares for the above even if they turn out to be ok, you then can cross them off the list.

Sorry cannot send photo, cannot make it small enough.

Odysseus
Bav 38