Ok, here is an answer, engine warm to the touch.
Page 15.16 of the Bentley says engine oil temp 30 degree C (86 F) for
diesel engine compression test.
Page 15.20 says oil temp 30 degrees C (86 F) for waterboxer compression
tests.

Presumably, you should run the engine for a minute or 2, wait a couple
minutes, pull all the plugs, do the test. If the plugs burn your
fingers, wait longer.

Mark

Anonymous Digest wrote:

> Well, first of all, no one has answered the issue of whether the published

> specs are for a warm engine or a cold one. I think a good point was made
>
>in that dry or oiled in the cylinders will have an effect as well.
>
>Which way was the testing done?  I bet if it was done cold, doing it on a
>hot/warm motor would increase those numbers a bit.
>
>