In article ,
"Roger Long" wrote:

My outlook is probably effected somewhat by watching the motorcycle
size battery in my plane start the 160 HP, high compression, engine
briskly on even below zero days.

BTW the 1,2 Both switch is an anachronism that I'll be ditching as
soon as I can get the boat back to Maine and overhaul the whole
system. There are very inexpensive battery management and charging
systems now that charge the batteries while leaving them isolated from
each other for normal loads.

--

Roger Long

There is a BIG difference between a DIESEL engine and a Gasoline engine,
when starting in cold weather. Comparing the two is "Apples and Oranges"
A diesel has a higher Compression Ratio than a Gas engine. Gas
volitilizes at a much lower temp than diesel fuel. Gas engines have
Spark Plugs that ignite the fuel/air mixture, and provides the required
heat of ignition. In a diesel with no glowplugs the only heat generated
is the Heat of Compression, which takes a while to build in the cyl.
That's why they invented Glow Plugs, and Intake Air Manifold Heaters,
to heat the fuel/air past the ignition temp.

Me