Ruggerini rm90 won't start
I’m trying to get a Ruggerini RM90 single cylinder diesel running, but it refuses to start and I’m running out of ideas.
What I already checked/did:
- Clean fresh diesel
- New fully charged battery
- Engine cranks strongly
- Injector was rebuilt by a diesel specialist
- New injector needle installed
- Injector opening pressure adjusted/tested by specialist
- Fuel system fully bled
- No more air bubbles visible in the return line
- When I disconnect the injector, I can see fuel pulsing from the high pressure line while cranking
- White smoke while cranking
- Engine occasionally makes “popping” sounds like it wants to start
- If I remove the oil filler cap, I can feel air/blow-by coming from the crankcase while cranking
What confuses me:
- Spraying brake cleaner into the intake gives absolutely NO reaction at all
- Not even a small increase in firing
Decompression lever appears to function normally and returns correctly.
What else should I check?
Could this still be:
- low compression?
- valve clearance?
- injection timing?
- injector pump issue?
- sticking valve?
Why would it still not start even with brake cleaner?
Any advice from people familiar with Ruggerini/Lombardini diesels would really help.