Jump to content

Battery or Magneto Help


ValkyrieRider

Recommended Posts

Ok, I am embarrassed to admit this - but the first step is to fix my issue is to admit my mistake.  

So, after my last flight, almost three weeks ago, I put up the battery tender on the battery but I inadvertently reversed the terminals.  Yes, I put the negative clamp on the positive terminal and opposite for the negative terminal.  The battery tender was on in for about three weeks until I went to fly it yesterday and realized what I had done.  I went through my regular preflight checks and everything else seemed correct.  I have a pre-oiler so I usually check the lights and run the pre-oiler and putting pressure not he oil system before I do my external checks.  Turning on the Master switch, checking the lights and running the pre-oiler all seemed normal with no indication of a problem with the battery.  After completing the rest of the preflight I attempted to start the plane ('65 M20C) like normal, all electronics lit up normally, but turning the key on the magnetos and nothing happened.  No attempt to turn the prop, nothing at all.  I attempted it a couple times but nothing each time.  I put the plane away and decided to pull the battery assuming the battery would be bad, even thought the JPI900 showed that I still have 12.1 volts.  I took the battery to O'Reilly Auto Parts and asked them to check the battery volts, which showed about 12.6 and put the battery under a load and their tester showed that it was a good battery.  They said that maybe a breaker tripped or a relay tripped.  I assumed it wasn't a breaker as all the electronics seemed normal with the master switch on.  Relay?  I don't know.

 

What would you recommend?  What can I check, or what else could be wrong?  Could the magnetos been messed up because of it?  Is there a relay that would have tripped to save the magnetos?  

 

Help...

 

 

 

Link to comment
Share on other sites

See if I have this right...

  • The battery got fully drained for about three weeks, down to zero, zippo, nada?
  • You knew this, so you removed the battery and charged it up, it came back to life so it seems?
  • You never tried to turn things on with the battery charger supplying -12 volts... right?
  • expect the battery to be weekend, and it’s capacity to be challenged...
  • But, everything should still be operating as normal...
  • Get our the volt meter, and prove to yourself... starting at the battery, going to the cigarette lighter That 12volts is showing up everywhere...

Very often, cleaning terminals, using the terminal grease, and proper battery installation techniques allow the electrons to flow fully without resistance...
 

 

PP thoughts only...

Best regards,

-a-

Link to comment
Share on other sites

As a follow on, no you probably didn’t hurt the mags, and depending on your charger if it sensed a reverse hook up it should have shut down, but cheap battery tenders don’t have the sensing circuits. 
I would suspect you have another electrical issue that may or may not have been caused by the reversed leads. 
Brian

  • Like 4
Link to comment
Share on other sites

1 minute ago, carusoam said:

See if I have this right...

  • The battery got fully drained for about three weeks, down to zero, zippo, nada?
  • You knew this, so you removed the battery and charged it up, it came back to life so it seems?
  • You never tried to turn things on with the battery charger supplying -12 volts... right?
  • expect the battery to be weekend, and it’s capacity to be challenged...
  •  

 

@carusoam Thanks for asking the clarification ... 

  -  I am not sure about whether the battery drained or not - will a battery tender, with the very low charging cause it to drain?  When I put the plane away three weeks ago the battery was strong, I just have a practice of putting the tender on it because of the heat inside my hangar in Phoenix, I want to ensure the battery stays strong.  I also forgot to mention, this battery is fairly new as I installed just this last April.  So I am not sure if it ever drained at all, or if the tender has a built in security system that prevents dummies like me doing what I did?

  -  I never charged the battery after I realized it wouldn't start the plane.  I took it out of the plane, as is, and the charge seems to be good.

  -  I never had a full battery charger on the battery only the little tender trickle charger.  I did turn on the master when I first arrived at the airport and checked my lights and ran the pre-oiler, all seemed normal.  After the preflight I went through my normal procedures with I used the pre-oiler a second time, it put 41 pounds pressure on the oil system, like normal, but when I turned the magnetos, nada, zippo ... 

  -  The Auto parts store seemed to think the battery was strong and something down stream must be causing it to not start. 

 

Thoughts?  (from a non-A&P/IA, but awesome pilot)??

 

Link to comment
Share on other sites

11 minutes ago, orionflt said:

Check to see if the positive and negative are now reversed on the battery after being on the charger for three weeks. 
 

brian

Brian, wouldn't the battery tester have identified that?  I know he has the negative on the negative terminal, etc. and it ready strong?

Link to comment
Share on other sites

8 minutes ago, orionflt said:

As a follow on, no you probably didn’t hurt the mags, and depending on your charger if it sensed a reverse hook up it should have shut down, but cheap battery tenders don’t have the sensing circuits. 
I would suspect you have another electrical issue that may or may not have been caused by the reversed leads. 
Brian

As much as I wish it weren't so, I suspect you might be right.  Any ideas as to what a non mechanic could do to test or check?

Link to comment
Share on other sites

If the battery didn’t drain...

Hooking the charger up backwards has had no ill affect...

What is confusing is the statement about turning on the mags and there was no effect...

 

Lets discuss what you did to try and start the plane...

Do you have an ordinary ignition switch?

Or a fancy push to start switch with separate mag switches?

 

Link to comment
Share on other sites

Depends on the tester, it could have shown -12.1v and the- wasn’t noticed

there is also a circuit breaker for the starting circuit, check all your breakers  to see if any are out. 
 

I doubt the battery is negatively charged, but start with the obvious stuff before ripping deep into the systems 

 Brian

  • Like 2
Link to comment
Share on other sites

Expect the tender to possibly have protection for dumb moves...
 

The battery was working to operate the pre-Oiler? Or is that completely separate?
 

What is working, what is not working?

 

Like Brian mentioned above... check all the CBs to be pressed in...

Next steps were expected to be turning the key hearing the starter vibrator... and the click or  the starter turning... after you pressed the key to start...

 

PP thoughts only, it’s been a while since I flew an M20C...

Best regards,

-a-

  • Like 1
Link to comment
Share on other sites

If you turn on the master and your lights, jpi, etc come on, then the master relay is working.  You need a digital voltmeter ($35) and the electrical diagram to test the battery and then follow the voltage downstream (with the master on) to see where it ends.

If the master switch still lights up the panel and cig lighter, but the starter doesn’t crank, I’d be testing the starter solenoid.

The mags are fine and not affected by this.  That’s my non-a&p but somewhat educated opinion.

  • Thanks 1
Link to comment
Share on other sites

6 minutes ago, carusoam said:

If the battery didn’t drain...

Hooking the charger up backwards has had no ill affect...

What is confusing is the statement about turning on the mags and there was no effect...

 

Lets discuss what you did to try and start the plane...

Do you have an ordinary ignition switch?

Or a fancy push to start switch with separate mag switches?

 

Ordinary, turn to both magnetos and the prop starts to turn.

 

Link to comment
Share on other sites

2 minutes ago, carusoam said:

Expect the tender to possibly have protection for dumb moves...
 

The battery was working to operate the pre-Oiler? Or is that completely separate?
 

What is working, what is not working?

 

Like Brian mentioned above... check all the CBs to be pressed in...

Next steps were expected to be turning the key hearing the starter vibrator... and the click or  the starter turning...

Best regards,

-a-

@orionflt and @carusoam Thanks a million, so far.

I will go to the airport tomorrow and double check all of the circuit breakers to verify none has tripped.  I didn't "notice" any when I tried to start the other day, but honestly, I could have missed this.

Yes, the battery worked to power up the JPI900 and the pre-oiler.  The pre-oiler is separate but can be operated with just the battery power when the master switch is on.  The pre-oiler pulls a little voltage so do have a tendency to do this prior to pulling the tender, that way it can add a little charge back to the battery while I am finishing the preflight.  The pre-oiler definitely worked both times, just like normal.


The next steps unfortunately were silent.  I didn't hear any vibrator or tuning - completely quiet.

 

 

 

Link to comment
Share on other sites

7 minutes ago, Ragsf15e said:

If you turn on the master and your lights, jpi, etc come on, then the master relay is working.  You need a digital voltmeter ($35) and the electrical diagram to test the battery and then follow the voltage downstream (with the master on) to see where it ends.

If the master switch still lights up the panel and cig lighter, but the starter doesn’t crank, I’d be testing the starter solenoid.

The mags are fine and not affected by this.  That’s my non-a&p but somewhat educated opinion.

It sounds like the starter solenoid would make sense - but as I said, I am definitely not a mechanic and do very little wrenching myself because of this lack of knowledge.  

How would I check to see if the solenoid is the issue?

Link to comment
Share on other sites

3 minutes ago, carusoam said:

Time to get help with your procedure...

putting the Switch to both, does not activate the starter...

Seems like it’s been a while since you have had the opportunity to use the plane..?

PP thoughts only, not a CFI...

Best regards,

 -a-

Actually I just flew it three weeks ago from Phoenix, AZ to Michigan and Ohio and returned - the plane performed tremendously.  I try not to let it go more than two weeks flying, so rarely does it go three weeks just sitting.  My wife and I were traveling in big sky country, at Glacier National Park for a couple weeks to celebrate 30 years of marriage.  So it normally flies regularly.

 

  • Like 1
Link to comment
Share on other sites

Depending on the switch you have...

There are three that are common to Mooneys...

1) Turn the key All the way to the right, then push the key in... (typical for O360s)

2) Turn the key all the way to the right, and hold it there... (modern Mooney standard)

3) push the red start button... (some electronic ignitions use this)

 

If you went to ‘both’ on the ignition switch... you have properly grounded both mags, but didn’t get to the start position... yet.

It is quite possible that your 50year old Bendix ignition switch needs help...

There is a Thread around here where somebody is discussing OH or buying a new switch...

See if we can get your memory up to speed... or it’s a trip to the airport to get the details of what you have going well... :)
 

It’s Still kinda early out there...

Best regards,

-a-
 

 

Link to comment
Share on other sites

4 minutes ago, ValkyrieRider said:

It sounds like the starter solenoid would make sense - but as I said, I am definitely not a mechanic and do very little wrenching myself because of this lack of knowledge.  

How would I check to see if the solenoid is the issue?

Depending on model and year, the starter solenoid is on the engine side of the firewall just in front of the pilots feet.  If you remove the pilot side, “cheek” cowling you should see it.  Checking can be, shall we say, exciting and windy because it’s powered when the key is turned and pressed in.  Don’t hurt yourself.  Involve a mechanic when you’re over your head, this shouldn’t be a difficult problem to trace or fix.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

Electricity has to flow...

1) to the switch

2) then the starter relay (solenoid)

3) then the starter

 

Often you will hear sounds like...

The starter vibrator working (buzz box)

The click of the starter relay

The whirring of the starter, that didn’t engage...

If it’s quiet... a volt meter is your friend...

If you decide to have somebody else turn the ignition switch while you are outside the plane...  this is a sign that you have gone too far...

Better to discuss all the details you know are working, and the ones that aren’t with your mechanic...

Don’t let a good idea get away from you... safety is the most important...

Best regards,

-a-

 

  • Thanks 1
Link to comment
Share on other sites

6 minutes ago, carusoam said:

Depending on the switch you have...

There are three that are common to Mooneys...

1) Turn the key All the way to the right, then push the key in... (typical for O360s)

2) Turn the key all the way to the right, and hold it there... (modern Mooney standard)

3) push the red start button... (some electronic ignitions use this)

 

If you went to ‘both’ on the ignition switch... you have properly grounded both mags, but didn’t get to the start position... yet.

It is quite possible that your 50year old Bendix ignition switch needs help...

There is a Thread around here where somebody is discussing OH or buying a new switch...

See if we can get your memory up to speed... or it’s a trip to the airport to get the details of what you have going well... :)
 

It’s Still kinda early out there...

Best regards,

-a-
 

 

Thanks for the description between the different types.  Mine would be the the common Mooney one, turn all the way to the right then push in for the start.

It is still early (8ish) out here, so I really should run out there but supposed to be doing a honey-do right now, but want to pick Mooney expert brains first.  Sounds like the Solenoid that was mentioned and possibly now the Bendix ignition switch.  

Link to comment
Share on other sites

7 minutes ago, carusoam said:

Electricity has to flow...

1) to the switch

2) then the starter relay (solenoid)

3) then the starter

 

Often you will hear sounds like...

The starter vibrator working (buzz box)

The click of the starter relay

The whirring of the starter, that didn’t engage...

If it’s quiet... a volt meter is your friend...

If you decide to have somebody else turn the ignition switch while you are outside the plane...  this is a sign that you have gone too far...

Better to discuss all the details you know are working, and the ones that aren’t with your mechanic...

Don’t let a good idea get away from you... safety is the most important...

Best regards,

-a-

 

Great advice, thank you.  I will start with this list and what @Ragsf15e has recommended.  I obviously am willing to learn and want to learn to do some more troubleshooting myself, but I know my limitations mechanically.

 

Appreciate your help gentleman, I will report back what I find ... thanks.

  • Like 1
Link to comment
Share on other sites

1. The magnetos have no connection to the battery.

2. Connecting a battery tender backward should not cause a problem. More sophisticated ones will have a protection circuit and even cheapos should have a fuse.

3. An open circuit battery voltage of 12.6 volts indicates that the battery is about 75% charged.

4. Turn on some lights and energize the starter. If the battery is just too week to run the starter, the high current draw of the starter will dim the lights very significantly. If the lights don't dim, then the problem is that the starter is not being energized. The problem could be a circuit breaker or fuse, the ignition switch or the starter relay or some wiring or the starter itself. 

Skip

  • Like 5
  • Thanks 2
Link to comment
Share on other sites

@PT20J @M20Doc @GeeBee Thank you for the information.  I will use this to troubleshoot today and hopefully be able to narrow it down to the culprit.  It sounds like it would make sense to charge the battery to 100% before putting it back in the plane.  Again, VALUABLE information, and I appreciate your time and help.

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.