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Comet breather info needed


Well Known and Active Forum Website User
VOC Member
I don't know exactly what the Comet breather is and how does it work.
Can someone please tell me where to find information?

chankly bore

Well Known and Active Forum Website User
Non-VOC Member
Richardson p. 120. Note spindle slot faces down. On drive side crankcase seeA71/1AS at "D" Be careful that the slot in the breather sleeve is aligned correctly relative to the "B" tooth and widen the slot to 3/8" and a knife edge as P.E.I. recommends. If in doubt as to correct timing the procedure for checking is as follows: 1] obtain a dentist's mirror, a degree plate, a cushion and a length of 7/16" i.d. hose. Now, standing on your head on the drive side (use the cushion), blow into the hose affixed to the breather pipe whilst turning the motor and observing the degree plate affixed to the crankshaft. The dentist's mirror will help. The port should close about 30-40 degrees after bottom dead centre. I hope you don't get a sore head! Cheers, F5AB/2A/7945 since 1970
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