On one Mag? Temptation and decision

Roger Halstead wrote in message . ..
On Sun, 28 Dec 2003 19:14:30 GMT, "Roger Long"
om wrote:

Absolutely, positively, do not fly on one mag if the engine is designed for
two! The second mag is not just for redundancy.

The two spark plugs light off the cylinder charge in two separate places.
Ever heard of burning your candle at both ends? The combustion takes place
faster so the burning is over when the exhaust valve opens and things have
time to cool down a bit. With one mag, the exhaust will be hotter and, in
some cases, combustion still taking place when the exhaust valve opens.
This can burn valves. On some engines, it can even damage the exhaust
piping.


I would think with incomplete combustion it would be cooler in the
cylinder and hotter in the exhaust stacks.

And it's not that much hotter in the exhaust stacks either. On a
single mag, I usually see my EGT rise about 50 degrees. Unless you're
leaning hard and making lots of power, I wouldn't worry too much about
running on one mag.

John Galban=====N4BQ (PA28-180)