Pre-J Mooney Jump Start Procedure

[Mooney-Shiner]

Good morning, esteemed group!

My battery seem to be getting weaker on the start up. It is absolutely due for a replacement (going with EarthX).

HOWEVER, I would like to check that I only have a battery issue. So my plan is to use my one pin (Piper style) jumper cables to connect to my car battery, and give my 67F model a start. If it starts then I know that I only have an issue with battery. If it won't start, then I will have to dig deeper.

 

I read through my 67F POH, SMM and even this board but still can't find a Mooney's published jump start procedure. Where should I look? If there is factory installed jumper plug, shouldn't there be an instructions on how to use it?

Thank you

 

[jetdriven]

There's no procedure because you're not supposed to do it. You will possibly kill the alternator or the regulator or both trying to charge a dead battery with the airplane. Plus, it needs to have 80% capacity to be airworthy so it should be changed anyway. Also, the earth X has about half the capacity of the lead acid battery so, you only have about 20 or 30 minutes of reserve capacity instead of an hour.

[Mooney-Shiner]

8 minutes ago, jetdriven said:

There's no procedure because you're not supposed to do it. You will possibly kill the alternator or the regulator or both trying to charge a dead battery with the airplane. Plus, it needs to have 80% capacity to be airworthy so it should be changed anyway. Also, the earth X has about half the capacity of the lead acid battery so, you only have about 20 or 30 minutes of reserve capacity instead of an hour.

Thank you. I'm NOT trying to start a dumpster fire, but why would Mooney Factory installed something that "you're not supposed to use?" And I'm saying this with utmost respect to your experience and knowledge. 

Edited August 11, 2024 by Mooney-Shiner

[jetdriven]

They installed that so you can start the airplane from a power cart without using the ships battery at all. It actually has its own separate contactor it powers, the aircraft directly off of the external power cart. But it is with the understanding that the battery is not depleted or it's defective or it's missing, just that you don't want to deplete it trying to start it in cold weather. Or if you want to do a bunch of avionics work and you don't want to run the battery down.

[Ragsf15e]

All the stuff @jetdriven said is true, however if you just want to see if it spins up faster (and the current battery isn’t dead, un-airworthy, etc), why wouldn’t you just hook it up with a normal set of car jumper cables like you would a car?  

[Mooney-Shiner]

Thank you.  Is there a published procedure for using power cart to spare perfectly functioning battery? 

[Mooney-Shiner]

16 minutes ago, Ragsf15e said:

All the stuff @jetdriven said is true, however if you just want to see if it spins up faster (and the current battery isn’t dead, un-airworthy, etc), why wouldn’t you just hook it up with a normal set of car jumper cables like you would a car?  

Thank you. The aircraft jumper wires are much longer than my car jumper wires. Plus I want to make sure that there is a process prescribed by the factory manual.

Edited August 11, 2024 by Mooney-Shiner

[N204TA]

The problem with using a Piper one-pin jumper cable is that the airplane needs to have a matching external power receptacle which Mooney doesn’t.  There is an approved external power system but it uses the standard three-pin plug and has its own electrical relay.  The only way to jump start our old airplanes is to get another battery source as close as possible and use standard automotive jump start procedures.  

I’n sure that Mooney did not publish a procedure because it’s not exactly a safe thing to do, standing behind a soon-spinning prop with panels open, jumper cables hanging out in the prop wash, etc.  In you look in the troubleshooting section of the MSM, you’ll see that everything they recommend involves just removing and replacing the battery.  

[Shadrach]

3 hours ago, jetdriven said:

There's no procedure because you're not supposed to do it. You will possibly kill the alternator or the regulator or both trying to charge a dead battery with the airplane. Plus, it needs to have 80% capacity to be airworthy so it should be changed anyway. Also, the earth X has about half the capacity of the lead acid battery so, you only have about 20 or 30 minutes of reserve capacity instead of an hour.

Are generators as susceptible to damage when starting on a dead battery as alternators?

[1980Mooney]

3 hours ago, Mooney-Shiner said:

Good morning, esteemed group!

My battery seem to be getting weaker on the start up. It is absolutely due for a replacement (going with EarthX).

HOWEVER, I would like to check that I only have a battery issue. So my plan is to use my one pin (Piper style) jumper cables to connect to my car battery, and give my 67F model a start. If it starts then I know that I only have an issue with battery. If it won't start, then I will have to dig deeper.

 

I read through my 67F POH, SMM and even this board but still can't find a Mooney's published jump start procedure. Where should I look? If there is factory installed jumper plug, shouldn't there be an instructions on how to use it?

Thank you

Following  @N204TA highlight of Piper 1 pin vs Cessna/Mooney 3 pin external power adapters:  Are you saying that your Mooney has a Piper style single pin receptacle mounted either internally or with a weather proof external door?  (Like pic below?)

If so it was not installed by Mooney at the factory and it is not the the Mooney Retrofit External Power Receptacle 940115-503 "Installs external power receptacle M20E,F,J,K".  Mooney used the Cessna style 3 pin external power adapter. (see below).

If you actually have a Piper single pin connector then check your logs to see who/when it was installed.

PIPER STYLE ONE (1) PIN

CESSNA OR MOONEY THREE (3) PIN ADAPTER

 

 

[BlueSky247]

I would think if we’re talking a 14v plane, it would make more sense to have a battery tender style pigtail run to the baggage compartment. Then just use a ctek or similar aviation grade smart charger for a few hours to get up to at least the 80% mark. 

[Hank]

In 17 years of ownership, I've jumped my C one time. We used regular car jumper cables. The poor sot who unhooks the cables and reinstalls the battery cover has to both know what he's doing, and be careful. (No, I was the guy inside who turned the key; some careful, knowledgeable soul was outside helping.)

After the flight (possibly an Instrument training flight), I made sure the battery cover was properly installed and the two cotter pins faced in opposite directions. 

It works, but it's likely not recommended, unless your battery is in the aft compartment and not mounted to the firewall like mine is . . . .

[N201MKTurbo]

Don’t take the battery cover off. Hook the ground clip onto the bolt where the ground cable hooks to the airframe and hook the positive clip onto the master relay bolt where the positive battery cable connects.

[Joshua Blackh4t]

I have successfully jump started a Cessna 150 from one of those boost packs.

It was a strange case where it started fine cold, then after an hour flight, it wouldn't turn over. The engine gets tighter when hot.

We left the battery cover off for safety to the person removing the booster and it got me home.

Jump starting is pretty much SOP for ultralights. Jump it from a car, let it warm up/charge the battery, shutdown and remove everything and start normally.

As for the OP who wants to test the battery, would your friendly local mechanic have a spare battery to try?

Also, on my E model, I improved my starting by servicing the starter solenoid. I had it 2 years and didn't realise the terminal was loose and not giving me full amps.

[1980Mooney]

4 hours ago, jetdriven said:

They installed that so you can start the airplane from a power cart without using the ships battery at all. It actually has its own separate contactor it powers, the aircraft directly off of the external power cart. But it is with the understanding that the battery is not depleted or it's defective or it's missing, just that you don't want to deplete it trying to start it in cold weather. Or if you want to do a bunch of avionics work and you don't want to run the battery down.

That may be true on some Mooneys - maybe the later ones with multiple batteries.  But on the M20J, the plane's battery and aux cable which is connected to the power cart/car engine are wired together in parallel when the Aux contactor closes.  There is no bypass of the main ships battery ever.

M20J Ser. No 237

M20J Ser. No 1256

Edited August 11, 2024 by 1980Mooney

[Mooney-Shiner]

4 hours ago, 1980Mooney said:

Following  @N204TA highlight of Piper 1 pin vs Cessna/Mooney 3 pin external power adapters:  Are you saying that your Mooney has a Piper style single pin receptacle mounted either internally or with a weather proof external door?  (Like pic below?)

If so it was not installed by Mooney at the factory and it is not the the Mooney Retrofit External Power Receptacle 940115-503 "Installs external power receptacle M20E,F,J,K".  Mooney used the Cessna style 3 pin external power adapter. (see below).

If you actually have a Piper single pin connector then check your logs to see who/when it was installed.

PIPER STYLE ONE (1) PIN

CESSNA OR MOONEY THREE (3) PIN ADAPTER

 

 

Yes, strange. I was under impression that one pin (Piper style) is a standard for pre-J Mooneys...

 

[Mooney-Shiner]

5 hours ago, BlueSky247 said:

I would think if we’re talking a 14v plane, it would make more sense to have a battery tender style pigtail run to the baggage compartment. Then just use a ctek or similar aviation grade smart charger for a few hours to get up to at least the 80% mark. 

My battery is on Battery Minder the entire time that it is sitting. My Concorde is just old and tired, so I will be replacing it. BUT I wanted to make sure it is only battery that I'm having a problem with.

[Mooney-Shiner]

4 hours ago, Joshua Blackh4t said:

I have successfully jump started a Cessna 150 from one of those boost packs.

It was a strange case where it started fine cold, then after an hour flight, it wouldn't turn over. The engine gets tighter when hot.

We left the battery cover off for safety to the person removing the booster and it got me home.

Jump starting is pretty much SOP for ultralights. Jump it from a car, let it warm up/charge the battery, shutdown and remove everything and start normally.

As for the OP who wants to test the battery, would your friendly local mechanic have a spare battery to try?

Also, on my E model, I improved my starting by servicing the starter solenoid. I had it 2 years and didn't realise the terminal was loose and not giving me full amps.

I asked my AP about spare battery, but no joy.

Starter solenoid seems fine.

[Hank]

20 minutes ago, Mooney-Shiner said:

Yes, strange. I was under impression that one pin (Piper style) is a standard for pre-J Mooneys...

 

Depends on what the previous owner installed. My C ain't got nothin!

[Ragsf15e]

8 minutes ago, Hank said:

Depends on what the previous owner installed. My C ain't got nothin!

My 68F doesn’t either.

[1980Mooney]

28 minutes ago, Mooney-Shiner said:

Yes, strange. I was under impression that one pin (Piper style) is a standard for pre-J Mooneys...

 

Here is the Mooney Electrical Schematic for your pre-J F model showing the Aux Power adapter.

[Mooney-Shiner]

1 minute ago, 1980Mooney said:

Here is the Mooney Electrical Schematic for your pre-J F model showing the Aux Power adapter.

Thank you! Mine is 1967 as opposed to 1969 above. 

[1980Mooney]

11 minutes ago, Hank said:

Depends on what the previous owner installed. My C ain't got nothin!

 

2 minutes ago, Ragsf15e said:

My 68F doesn’t either.

Note that it was an "Option" as shown in the drawing for E and F models.  It was also an option for C and G using exactly the same schematic.

[1980Mooney]

23 minutes ago, Mooney-Shiner said:

Thank you! Mine is 1967 as opposed to 1969 above. 

OK here it is for your 1967.  You can find all the electrical schematics in the back of the Service Manuals which you will find in the "Downloads" Section of MS - just click on "Browse".

Notice that they connected the hot + lead from the battery to the lug on the Aux/External Power Relay (Solenoid) instead of to the Power Relay like on later models.  When the Aux/External Power Relay is energized (that is when the 3 pin connector plugged in and attached to a 12 v. power cart or car) then both the main ship battery and external power source are connected in parallel.

[Mooney-Shiner]

21 minutes ago, 1980Mooney said:

OK here it is for your 1967.  You can find all the electrical schematics in the back of the Service Manuals which you will find in the "Downloads" Section of MS - just click on "Browse".

Notice that they connected the hot + lead from the battery to the lug on the Aux/External Power Relay (Solenoid) instead of to the Power Relay like on later models.  When the Aux/External Power Relay is energized (that is when the 3 pin connector plugged in and attached to a 12 v. power cart or car) then both the main ship battery and external power source are connected in parallel.

Wow, secret pages of SMM! Actually first time seeing this drawing after fours years of staring at them. I had no idea that there is a supplement