Electrical question

[William Mattson]

I've had to charge my battery after night flights, battery get slightly low. I would assume alternator. I flew around today with a voltmeter connected to the cigarette lighter. I got 13.75 volts unless I turned on lights and pitot heat then it dropped.

I have had high oil temp. Last night I went for a 1.5 hour flight and temp stayed at 220. I reduced power did a 160 knot decent, oil temp rock solid temp never moved. I did notice today that if I shut of the alternator the temp dropped to 190 turned back on and instantly 220. Is there any way the alternator is messing with the temp guage?

Thank you,

Bill

1st year owner still working on the gremlins.

[N3322G]

Hmmm. I'm guessing here - could just be that battery is getting old. Can you tell the last time it was replaced? We use the Concorde and still replace it every 4 years just cause we don't want to get stuck somewhere.

We usually do the same for our cars but I let my Mini Cooper slide and got a whole 7 years. Knew it was going as it took a tad longer to start the car - then we left the car alone while we traveled for a few weeks - it obviously pouted the entire time and would not start when we got home. Fed it a new battery and it likes me again

Hope your issue is as simple.

[William Mattson]

Left that out. That was my 1st thought as well, I just replaced my battery yesterday. The last one was in there since March. I don't think it's bad either, I'm going to charge it and do a load test.

[N3322G]

Wow, new battery in March so that shouldn't be it. After that I'd guess wiring or connections. Does yours have the copper battery cables?

http://bogertaviation.com/index.php?pag ... &Itemid=23

As you may know from my other posts, I don't pretend to be an expert. I am a learn by checkbook owner, if I've had a problem, I at least know one cause of it and what fixed it. In this case, I'm simply doing my best to guess what might cause this situation.

[David Pyle]

Bill,

Do we know what is your Comanche? Would help connect with those of similar persuasion. Copper cables? Battery location? The cigar lighter volt meter is a good back up. Left one there full time. Battery tester also good. I like Concords also, but some think they do not have the cranking power of the conventional. If I was having electrical problems I kept a smaller 12 volt like a wheel chair battery in the airplane. It will crank the engine if the #1 is dead or dying.

[William Mattson]

I have a 250, battery aft the baggage compartment. I do have the bogart cables. Flying last night the alternator quit providing power. I will be replacing alternator. I will find out if this fixes the oil temp guage reading high.

[Jay]

One easy item to check that seems to cause more trouble than it should is the ground strap. I had similar issues, and it was a corroded and lose ground strap.

Jay

[William Mattson]

Took off alternator. Bad diodes only producing 10 amps. I having it overhauled. It only had 220 hours on it. I am waiting to see if the ac current leak was messing with the oil temp gauge.
It happened at just the right time as my annual is scheduled to start in 10 days.