I've just had a look using a search engine to try to find some information on your " Ingorsol Rand 150" compressor.. It comes up with a lot of Ingorsol Rand compressors with 150 in the number. Can you give us some information about the compressor ? power rating (Or cu ft per minute and pressure.) Is it single or multi cylinder. Is it belt drive or direct drive ? If it is belt drive could the belt be slipping ?
Edit. I have just re read your first post and realise that you have eliminated a slipping belt.
Edit 2. If the rings were leaking I would expect to hear air coming out of the oil filling point on the crank case.
Les.
Edited By Les Jones 1 on 26/03/2017 18:01:21
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