Re: Timeing a Clipper Deluxe without a timeing light

Posted by DavidPackard On 2017/4/23 15:58:43

'Back in the day' we would static time reciprocating helicopter engines by slipping a piece to cellophane paper between the magneto points and slowly rotate the engine toward TDC. When the paper became somewhat loose we would check if the timing marks were aligned. These were 'un-excited' magnetos with impulse couplings, so the test light technique would not work (no voltage unless the magneto was spinning). The same 'super thin feeler gauge' technique was used on various rigging points of the controls. Since there was no stigma attached to smoking back then the supply of cellophane paper was somewhat unlimited. The only limitation is that it will only work well if the points are smooth. Pits are OK, but the 'mountain peaks' had to go. If a test light is not available this alternate method is likely to work just fine. Detonation will let you know if the dynamic (static + centrifugal) advance has gone a step too far. Labored cranking is another symptom of excessive static advance. One of those two conditions will ultimately limit the amount of advance you can set the timing to.
dp