Location of Voltage Regulator

[n5756k]

Where is my voltage regulator located on my 1984 (24-1463) M20J?

[carusoam]

Most older Mooneys got it mounted up on the engine side of the firewall.  Some newer Mooney's got it mounted on the interior side of the firewall.

Chasing the 'field' wire from the alternator might be a way to find it...

It has a wire connected to the fuse panel that may be helpful.

Your POH will have a simple wiring diagram with the major parts indicated.  The voltage regulator will be one of them...

PP thoughts only. Not a mechanic.

Best regards,

-a-

 

[ArtVandelay]

My J has it copilot foot well on the right side.

[n5756k]

I found it right under the co-pilot panel. I keep getting the high/low voltage light with the alternator tripping off line.

Tom Moquin 

M20J

[carusoam]

What do you have for a voltage indicator?

You might have a JPI that possibly records Volts during a flight?

A Zeftronics voltage regulator is pretty new technology.  It may have some LEDs that can help identify a challenge that it knows about.  It might have options for adding Led lights to the instrument panel...

Check all the connections for tightness and cleanliness... could be a loose wire or some oxidation on a terminal...

Best regards,

-a-

Edited March 11, 2017 by carusoam

[n5756k]

Yes, I'll trying looking at the cannon plug connection.

Tom M20J

[ArtVandelay]

44 minutes ago, n5756k said:

Yes, I'll trying looking at the cannon plug connection.

Tom M20J

It's grounded through the case, so make sure your ground connection is good and secure.

[n5756k]

Well I dropped the airplane off at Aircraft Systems, Inc. (Rockford, IL, KRFD). If anyone can figure this out Terry Norris can. Sometimes when I try to engage the starter all electrical power drops off line. If I toggle the master switch several time, sometimes it come back. Other times during cruise the alternator goes off line and I see almost 30 amp draw. I've changed the master switch, battery solenoid at the battery; and just last week at annual the mechanic changed the battery (which wasn't old and seemed fine to me). The problem is the problem is intermittent. It is hard to figure out when you can't duplicate it on demand. Hope this solves the problem, we want to fly the Mooney to Sun N Fun next month.

 

[carusoam]

Wild guess...  there is a bad solenoid switch in there asking to be replaced.  Check for evidence that the right one got replaced...

PP idea only, not a mechanic...

Best regard,

-a-

Edited March 14, 2017 by carusoam

[Guest]

4 hours ago, n5756k said:

Well I dropped the airplane off at Aircraft Systems, Inc. (Rockford, IL, KRFD). If anyone can figure this out Terry Norris can. Sometimes when I try to engage the starter all electrical power drops off line. If I toggle the master switch several time, sometimes it come back. Other times during cruise the alternator goes off line and I see almost 30 amp draw. I've changed the master switch, battery solenoid at the battery; and just last week at annual the mechanic changed the battery (which wasn't old and seemed fine to me). The problem is the problem is intermittent. It is hard to figure out when you can't duplicate it on demand. Hope this solves the problem, we want to fly the Mooney to Sun N Fun next month.

 

Worn brushes in the alternator?

Clarence

[Oldguy]

Have seen many of your symptoms occur with a loose or dirty ground. On an '81 J it was the cable from the battery to the air frame. Looked fine and was tight, but once the connection was loosened, polished with an emery cloth and tightened the problem was gone. Hope yours is that simple.

BTW, flying your plane's younger sibling - 24-1492.

[air cooled dad]

This dinosaur came out of my '75F today. I spy a Jurassic voltage regulator.  Anyone want it?

In my quest to solve the windshield wiper ammeter I swapped out a master switch. Cleaned a bunch of grounds.  Found a loose ground on the alternator. Found another loose wire on the ammeter gage. Still messed up.  

Voltage on the JPI was always 13.8.  Old voltage regulator kinda waffled between 13.2-13.8.  I live next to aircraft spruce so I picked up a new Zeftronics voltage regulator.  Works like a champ now. No more windshield wiper on the ammeter. I guess I could've adjusted the old one but I wanted a new one.  It's shiny. Lol. 

Good luck with your electrical problem.  Chasing these things can be a bear. I know I'm not a modern J but it should be close to mine.   Behind my VR, on the other side of the firewall, is the shunt. Next to that are two inline fuses to the vacuum and voltage high/low detectors. To help diagnose my problem I momentarily disconnected my high/low voltage detector.    Hopefully my picture will help you locate the items your looking for.

Jason

 

Edited March 16, 2017 by air cooled dad
Added stuff

[carusoam]

That is one of the most rewarding swaps...

The old sticks, stones and springs regulator was good back in its day.

open it up to see what's inside, or what's not inside.

Post a picture of that!

Did you use any of the warning LED outputs on the new one? It can signal a problem like the loose wire without you guessing what the windshield wiper is trying to tell you.  

Best regards,

-a-