Archive for tips
The GM-060 and big Aliva machines typically have Fenner / Globe piston air motors, typically the RM-410 (4 cyl. / 1-1/4” inlet / exhaust). These do have two exhausts (one straight out the back and one next to the air inlet).
Fred thinks that the air motor issue may be in the rotary valve (Item 2 on exploded parts diagram).
Suggests you try blowing airwith a little …