I know that nothing will suffice as a substitute for an actual compression test. That being said, I’d like to know if the following could be used as an indicator of an engine with good compression.

I looked at an 82 SD that had been sitting for several weeks. It was dead cold, and the owner put the key into the ignition switch and immediately fired up the engine without waiting for the glow plugs for even a second. It fired up immediately after less than 2-3 seconds of cranking. The ambient temperature was about 70 degrees. I asked him about this, and he said that he usually doesn’t need to use the glow plugs except in winter.

I would like to logically assume that the engine has relatively high compression; at least high enough to heat the air to allow combustion to take place without much cranking. Do you experts out there feel that this is a good enough indication of the condition of the engine?

Thanks again everyone!

(the quest continues….)