Low Voltage Troubleshooting?

[Guest]

Slipping drive coupling on the alternator.

[carusoam]

Hmmmmm……

@khedrei check the wisdom from doc above….

1) Your challenging situation is changing with time…

2) Low voltage  can be caused by three things… less voltage coming in… or more electrons being used… or a restriction in the electron’s pipe…

3) If your installed equipment hasn’t had additions, or your procedures haven’t changed… it could be something to do with the alternator not performing as well as expected….

4) Continental alternators don’t use belts to drive them… and have a clutch to protect them, or the engine from them…

5) What oil mist do you have?

If the clutch is supposed to be dry, and it’s getting oiled… that could cause some slippage…(?)

If the clutch is wearing out, it may have a seal leak too… (?)

6) Either way… check on the status of the alternator’s clutch… if it is like the starter’s clutch… it may leave unwanted extra parts inside the engine… (?)

 

Please note… These are PP guesses at best… not a mechanic.

Best regards,

-a-

[khedrei]

Thanks for the responses. I fired it up today and it appears the master switch wouldn't reset the problem. But running at 1200 rpm the voltage slowly kept up from 12.3 up to over 13.7 without a run up. Sounds like Clarence is onto something. Does anyone have a part number for a new one?

[Ragsf15e]

One other thing… since your issue is “all or nothing” for delivering current/voltage from the alternator, it’s unlikely to be a corroded connection.  Something stops working completely.  Maybe that helps, maybe it doesn’t, but I wouldn’t be sanding connections on this one.  I’d be looking at the VR, alternator, master switch, field cb, and alt cb. Probably in roughly that order.

Of course I’m neither a mechanic or ee.  Free advice is, well, free!

[Guest]

Easy to test and confirm a slipping drive coupling.  With the cowls off, slip your finger into the side of the alternator to hold the cooling fan, with your other hand turn the propeller slowly.  This is best done yourself, a helper won’t be able to tell if your finger tip is sore.

If you can hold the fan with your finger the drive is slipping.
 

From the engine IPC.

[khedrei]

Thanks a lot Clarence!  I will check that today.  My engine is an LB.  Would the part number be the same?

I will post my findings in hopes of helping the next guy.

[khedrei]

Checked on Spruce.  It appears its fairly universal to many Continental engines.  It simply specifies TSIO-360 with no reference to the MB or LB.  

$855 USD plus a core charge.  Will run 1400 Canadian with taxes.  Insane.  I assume buying a new alternator for 1200 bucks doesn't come with the drive...

Again, I will keep posted.

[Guest]

Same part over many models.  Installation is not complicated, but must be done right.  There was one on here recently that was assembled wrong and damaged the engine.

Clarence