Re: oilheads-digest V1 #54

["Edward Begley" <edbegley@xxxxxxxxxxxxxx>]

I'm an aircraft mechanic where engines have to be reliable.  Interestly they
still have air cooled opposed engines with pushrods a foot long or more and
are fired my two magnetos each independently firing one of the two
sparkplugs in each cylinder(lose one mag, one set of plugs, and have your
battery and/or your alternator, or harness leads to one of the plugs and
guess what you'll hardly notice it-a few rpm drop that's it-it'll run
perfectly fine.  We check the operation before takeoff before every flight
by shutting off one whole magneto and bank of plugs to verify this.  Some
might say it's adequated but man I've seen nothing I like better on the
experimental aircraft(which have different regs and therefore you see stuff
in them like modern cars have-electronic ignition,etc)  I'll take the old
design anyday when my butt is in the air.  It's simple and reliable!
Magnetos have points by the way and I've seen them run all the way to
overhaul(typically 2000 hours) without being replaced.  The overhead cam is
likewise extremely reliable.  Some have hydraulic lifters and you don't have
to adjust the valve clearance but some you do with feeler gauges just like
the BMW's.  In fact the engine with the longest TBO(time between overhual)
Lycoming 235 has manually adjustable valves with feeler gauges just like the
BMW!
- -Ed-

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