REFLECTOR: Lycoming starters

[NMFlyer1 at aol.com]

I was talking with B&C a couple weeks ago about the final wiring for my 
battery and starter circuts. I was asked if I had a Permanent Magnet Motor, or a 
field wound. At the time I didn't know and had to look up the Chevy Part and 
found out. Most Starters are permanent magnet motors and they are less efficient 
for high torque applications. 

As it turns out, I have a PMGR starter (permanent Magnet, Gear reduction) in 
the Chevy V-6 in my Velocity.  The Voltage rating is what they expect/need at 
the starter motor, usually after a few seonds of cranking. There is a pretty 
good explination of this in AeroElectric papers. 

In a canard-pusher, the starter situation is about as bad as it can get. 
Battery in the nose, starter in the back, long wires, etc. They say to optimize 
this, use good FAT wires, Good grounds, and an RG (or starved electrolyte, Glass 
mat, or many other terms) battery. This will make sure that the starter gets 
as much power as possible considering the situation. 

My old Cherokee 235 has the battery behind the baggage bulkhead, not great 
cables, and the old inefficient starter. Needless to say, when it is cold (or 
very hot) it shows up trying to start the O-540. I didnt want to spend 
mega-bucks to buy a new starter, or change out the cables if I didnt have to. So, I 
replaced the old style flooded cell battery with a new RG battery. The starter 
now spins much better and longer, and I have no starting problems at all. The 
lower internal resistance in the battery, and high cranking amps work wonders! 
They are also less prone to self discharging and cold weather problems. 
Yesterday I fired up the Cherokee after not flying it for 2 weeks. It was 27 degrees 
outside. No preblem. 

So, My advice would be to START with an RG battery. It is the easiest and by 
far least expensive starting point. It just may cure the problems (providing 
you dont have some defect in the system). If you still have problems, at least 
you know it is not the battery and you will be pleased with its performance 
anyway. 

Hope it helps. 

Kurt 
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