240D's glow plug light is only UP for about 2 seconds.
 

Dear friends:

My 1981 240D (manual transmission) is extremely hard to start.
I already did valve adjustments, replaced and flushed spin-on mail filter/inline pre-filter, changed engine oil/power steering but it's still extremely hard to start it with the ignition key. Only a push-start can start it up.

Now I suspect that the glow plug relay does not work properly. I did test all 4 glow plugs and they seemed to be OK (resistance ~ 0.5 - 0.8 Ohms). However, when I turned the ignition key to the #2 position, the glow plug light was only up for about 2 seconds before it was off again. The ambient temperature was about 60-65 Fahrenheit. Is this a symptom of a bad glow plug relay? Do you have any other suggestions (besides a low compression/worn piston rings) ?

BTW, I wonder whether a NEW diesel engine can just start right away when the ignition key is in START position, without needing
any pre-glow time when the ambient temperature is about 60 F
or more?

Thanks in advance for all your precious help.

Best regards,

Eric