Checking oil on an old joy rotary screw , tow behind , 4 cylinder

Hi Shuan,

If there's no oil level indicator on the little air receiver (the oil tank / air receiver / separator tank) .. then generally speaking, the oil must be filled up until it reaches the fill opening.

Normally, this tank is about filled for about 1/4th with oil. The top of the tank houses the separator filter.

All the best,

Cas