Power Everywhere but Starter?

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Re: Power Everywhere but Starter?

Post by 6298 »

Did you test the voltages?
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals
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6643
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Re: Power Everywhere but Starter?

Post by 6643 »

Do the voltage check first. If you're getting 13.5 - 14 volts at 1800 RPM then there's nothing wrong with the generator. If you are and the ammeter shows a discharge, and it shows zero or a "charge" at idle, then the meter is wired backwards. It's supposed to show current into (+) and out of (-) the battery. Sounds like it's showing current out of the battery as plus. Simple mistake, simple fix.

Assuming it is wired backwards, you're getting 10 amps of charge. Not bad for a 13 amp generator...

The generator brush is 1906984. Fresno sells a kit with brushes, bearings and seal. You may be able to get the brushes alone from Aerotech of Louisville.
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Re: Power Everywhere but Starter?

Post by 8209 »

Thank you John for all the help!
When your testing the voltage of the generator output where is the best place to check it? I want to make sure I'm looking for the right voltage in the right place. You're right, the gauge could be wired backwards, if it is it's been that way along time from the look of the wires on the gauge, but this plane hasn't flown regulars in over 15 years so anything a possible.
Thanks again, I really appreciate you monitoring my problems, it is great to be able to get advice that quick.
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Re: Power Everywhere but Starter?

Post by 6643 »

There's a lot of places you could test, and they'll each give you slightly different information. If you want generator output, connect the red probe to the "A" terminal of the voltage regulator,or the "A" terminal of the generator, whichever is more convenient. Connect the black probe to a good ground on the airframe. Expect to see 0 volts with the engine not running. Voltage should track RPM up to about 14 volts/1600-1800 RPM, at which point it should stay steady as long as the electrical load is constant.
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Re: Power Everywhere but Starter?

Post by 8209 »

Thanks John, that's exactly what I was looking for.
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Re: Power Everywhere but Starter?

Post by 6597 »

Did you ever get your beacon working? I had a helluva current draw on mine before I fixed it......just curious
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Re: Power Everywhere but Starter?

Post by 8209 »

I did NOT get my beacon fixed. I'm not even sure how to get to it. It's half way between the luggage compartment and the tail, I can't figure out how to even get to it. I'm too big to get in that hole. I need a little bitty guy that knows all about 71 year old beacons! ;)
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Re: Power Everywhere but Starter?

Post by 6643 »

You should be able to get it out from the outside...
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Re: Power Everywhere but Starter?

Post by 8209 »

Maybe, but it sure doesn't look like it. Everything comes up from each the bottom. It has about 6 screw that are on the outside and it looks like if I take them out the whole unit will fall into the fuselage. :?
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Re: Power Everywhere but Starter?

Post by 6643 »

Well, just because you should be able to doesn't mean they put it in the right way.... What brand is it? Got any pictures?
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