What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

replacing battery with Earth-x

seagull

Well Known Member
My -12 currently has an Odyssey PC680 battery. It is coming up on 5 yrs, and a bit over 400 hrs. The voltage is 12.2V after sitting a few days. I need to run some tests on it but think it is close to it's end of life.
I am considering getting a EarthX Lithium and was wondering if either the ETX680 or the ETX680C are a direct fit. Do I need to change the battery box also?
Anyone with experience changing over?
 
Pull your battery, and charge it up with a 12v battery charger for 24 hrs. that will put out 14.8V.

Take it off the charger and take a voltage reading. Should be initially 13.1 to 13.3 volts with a surface charge. Check it quickly, every day, same time of day during the week, 7 days straight.

You should not drop below 12.80 V in 7 days.
 
My -12 currently has an Odyssey PC680 battery. It is coming up on 5 yrs, and a bit over 400 hrs. The voltage is 12.2V after sitting a few days. I need to run some tests on it but think it is close to it's end of life.
I am considering getting a EarthX Lithium and was wondering if either the ETX680 or the ETX680C are a direct fit. Do I need to change the battery box also?
Anyone with experience changing over?

Gull,
To answer your question, I changed from the PC680 to EarthX several years ago. No, it is not a direct fit: The dimensions are not the same, but I was able to modify my existing Vans box to fit the EarthX. I have since changed over to their custom-fit box with the bracket on top to hold a blast tube for battery cooling, and recommend you go ahead and take this route:
https://earthxbatteries.com/shop/thermal-battery-box-etx680-900-900-vnt-1200

Here's the normal non-thermal box for ETX-680:
https://earthxbatteries.com/shop/aluminum-battery-box

You will absolutely love this battery.
 
Gull,
To answer your question, I changed from the PC680 to EarthX several years ago. No, it is not a direct fit: The dimensions are not the same, but I was able to modify my existing Vans box to fit the EarthX. I have since changed over to their custom-fit box with the bracket on top to hold a blast tube for battery cooling, and recommend you go ahead and take this route:
https://earthxbatteries.com/shop/thermal-battery-box-etx680-900-900-vnt-1200

Here's the normal non-thermal box for ETX-680:
https://earthxbatteries.com/shop/aluminum-battery-box

You will absolutely love this battery.

scroll,
I am sure I will like the battery, the specs are much better than the Odyssey.
Was your application a -12 with the Rotax?

Your 7A with YIO-360M1B may run hotter cowl temps than the 12.

I read Earthx is OEM for the RV-12is, if this is correct there is a Van's battery box or cooling system designed for it. I have the 912ULS, it should produce about the same cowl temps.

Did you connect the battery monitor wire to the supplied LED or to a Dynon input?

ninerbikes,
There is no question the battery is weak, after a full peak charge it reads 12.2V no load. Five years is a long life for one of these batteries considering the use and environment. I am being proactive before it leaves me stranded.
 
Good points, I had not considered the RV-12 application and don?t know the answers. Give Kathy a call at EarthX: I bet she knows.

I hard-wired the LED to my panel, because I don?t want some EFIS failure to hide a possible problem. The battery light is independent on my airplane.
 
My -12 currently has an Odyssey PC680 battery. It is coming up on 5 yrs, and a bit over 400 hrs. The voltage is 12.2V after sitting a few days. I need to run some tests on it but think it is close to it's end of life.
I am considering getting a EarthX Lithium and was wondering if either the ETX680 or the ETX680C are a direct fit. Do I need to change the battery box also?
Anyone with experience changing over?

What don't you like about the Odyssey battery? You are in the luxurious position of replacing a good quality battery on your time, at your leisure, before you have a failure. What are you trying to improve, the 5-year life? The reliability? I would (and did) replace my Odyssey with another Odyssey when it was time.

Just don't buy from Spruce unless you know what you are getting. They sold me a 925 Odyssey that was a year old according to the date code on the battery. They only had one in stock and I had possibly damaged my 3 year old 925 by leaving the master on so I changed it. You just can't beat the price point and reliability of the Odyssey.

-Marc
 
Last edited:
I read Earthx is OEM for the RV-12is, if this is correct there is a Van's battery box or cooling system designed for it. I have the 912ULS, it should produce about the same cowl temps.

This may not be the case. Legacy RV-12 is tightly cowled and 12iS cowling has louvers for added ventilation. Biggest concern might be on the ground when powered off. Legacy retains heat without adequate ventilation. When I "park" I open the oil door to let heat escape...
 
Just a datum point. I am currently replacing my Odyssey PC960 with an Odyssey PC960. Battery is 13.5 years in service. It doesn't owe me anything.

New Odyssey has a date code of 19333. Can I assume that means it was manufactured on the 333rd day of 2019?
 
New Odyssey has a date code of 19333. Can I assume that means it was manufactured on the 333rd day of 2019?

I wouldn't assume anything about a printed date code. Manufacturers often use internal code reference which consumer is not privy too.
 
There is nothing not to like about the Odyssey, but the Earthx will take 10 pounds off the plane, that is significant on a LSA.

You better run some weight and balance numbers if you remove 10lbs from the firewall location on your older 12. The earthX was used in the 12is because of the increase in weight from all the accessories that come with that engine like computers and fuel pumps. These accessories were located to balance the plane accordingly.
 
Smoke

My -12 currently has an Odyssey PC680 battery. It is coming up on 5 yrs, and a bit over 400 hrs. The voltage is 12.2V after sitting a few days. I need to run some tests on it but think it is close to it's end of life.
I am considering getting a EarthX Lithium and was wondering if either the ETX680 or the ETX680C are a direct fit. Do I need to change the battery box also?
Anyone with experience changing over?

You may want to read through this "IN-FLIGHT SMOKE INCIDENT REPORT" before replacing your AGM battery with Lithium. There may be some precautionary steps to take.

http://www.vansairforce.com/community/showthread.php?t=154336
 
You better run some weight and balance numbers if you remove 10lbs from the firewall location on your older 12. The earthX was used in the 12is because of the increase in weight from all the accessories that come with that engine like computers and fuel pumps. These accessories were located to balance the plane accordingly.

Also, much of the heavy stuff was put as far back as possible - behind the rear baggage bulkhead where it is difficult to access for maintenance. Makes sense that light battery was substitued up front to keep W&B hunky-dory.
 
UPDATE:
I tested the battery, it tested very good, (with this tester) for a 5 year battery. Next step is to compare the Dynon voltage with a different volt meter. The 12.2 (Dynon) voltage reading is what started this concern.

s6cAcTR.jpg
 
Autozone Auto Parts stores will test a battery under heavy load. This is a measure of internal resisitance and the battery's ability to deliver rated amperage.
 
Last edited:
Just a datum point. I am currently replacing my Odyssey PC960 with an Odyssey PC960. Battery is 13.5 years in service. It doesn't owe me anything.

New Odyssey has a date code of 19333. Can I assume that means it was manufactured on the 333rd day of 2019?

Google "odyssey battery date code" and the first hit is to a VAF post:

Since I purchased my 9A flying there wasn't any information either in the logbook or on the battery when it was installed.

So off I sent an email to the Odyssey.

My serial number on the battery is [FONT=&quot]06GCS061250340[/FONT][FONT=&quot] and there was a sticker on it that had 0769-2016 and under that number was 0606

Here is their reply:

[/FONT] The serial number?06GCS061250340 shows that the battery was manufactured on the 125th day of 2006 and the 0606 located under the 8 digit part number 0769-2016 indicates that the battery shipped from this facility in June 2006.



So no you know how to determine your Odyssey batteries real age.
 
Today I tested the battery after sitting with no load for 48 hours.

Measured at the battery the voltage was 12.84.
I powered the Dynon only and the reading at battery dropped to 12.1. At the same time the Dynon showed the battery at 12.0.
Next I turned on the landing light, nav lights, autopilot, and radio. The voltage at the battery was now 11.78 and the Dynon showed 11.6. The current used with everything on was 19 amps.

Note; the difference in voltage readings between the Dynon and my meter is roughly .1 volts, 10%, probably just variations in the calibrations.

My conclusion is the battery probably has a bad cell that can?t supply full voltage with a moderate load. I don?t expect it will suddenly fail but needs to be replaced in the near future.

I hope this info helps someone else.
 
Pulling 19 amps on a 165 to 175 aH battery is a very heavy load. I would expect the voltage to drop below 12.0.

With a brand new battery, showing 12.85 V at start, the Dynon SkyView Touch usually shows 12.2 to 12.3v in the yellow, right before starting. Depends on if the fuse for fuel pump is installed, or not. We generally start the motor without the electric fuel pump, let the Dynon boot up, get up to 2500 rpm to excite the fields of the alternator to get positive amps and charging at 13.0V, then put the fuse for the fuel pump back in the fuse holder.


I don't think you've so much a dying cell as much as you need to let it sit on a 14.4v max recharger for 48 hrs to desulfate as much as possible the individual cells, before putting back into service. I say 14.4v max, due the the AGM chemistry in this battery.

You'll know when the battery is dying or dead... you'll try to start it and it won't, the starter solenoid will just click . Next thing you know, it's possible you'll blow the 5 amp fuse on the electric fuel pump. Don't ask me how I know this, done this 3x in the past 15 months. 2x with new batteries from Aircraft Spruce under warranty. First one lasted 6 months, the second one 3.5. Did a complete electric current draw trouble shoot and came up blank.
 
Last edited:
We generally start the motor without the electric fuel pump, let the Dynon boot up, get up to 2500 rpm to excite the fields of the alternator to get positive amps and charging at 13.0V, then put the fuse for the fuel pump back in the fuse holder.

What is the logic behind that? I don’t understand why so many folks circumvent the electric fuel pump. Van’s has stated the need for running the electric pump in continuous mode as a safety measure, and as such, they did not provide a method for shutting it off.

It’s like pulling the Hoot Gibson circuit breaker on a 727 - most of the time not a problem. Sometimes, not a good idea…
 
The Rotax ULS alternator does not have an electrically excited field.
Instead, It has permanent magnets embedded in the flywheel.
-
The fuel pump fuse blows because it inadvertently touches the instrument panel during insertion.
The master switch should be turned off when replacing fuses.
-
I turn on the master switch, listen to be sure the electric fuel pump is running and check fuel pressure.
Start the engine and look for an increase in fuel pressure to be sure the engine fuel pump is running.
 
The fuel pump fuse blows because it inadvertently touches the instrument panel during insertion.

The fuel pump fuse can blow on its own if the battery voltage is quite low and a start is attempted (there are numerous instances mentioned here in the forum and I have seen it happen once my self)..

With the combination of ohms law, and the fuel pump being an inductive device, if the voltage is low, the current draw from the pump can get high enough while cranking the engine to blow the fuse.
 
What is the logic behind that? I don?t understand why so many folks circumvent the electric fuel pump. Van?s has stated the need for running the electric pump in continuous mode as a safety measure, and as such, they did not provide a method for shutting it off.

It?s like pulling the Hoot Gibson circuit breaker on a 727 - most of the time not a problem. Sometimes, not a good idea?

1. We've lost a few 5 amp fuses. Part of the routine now is that we do CCiGARR

Close Canopy, Controls, Instruments, Gas (which includes installing gas pump fuse back in) Attitude, Radio frequencies for tower, Run up.)

2. The Rotax 912 ULS engine designers have an adequate fuel pump that feeds the Bing carbs with enough fuel pressure under all conditions, when running gasoline without Ethanol, as well as with Ethanol, up to E-15 IF fed by gravity with wings overhead that keep the lines pressurized. The RV-12 doesn't have overhead wings.

3. Van's saw fit, in their engine specs, to add a bunch of fuel hoses, a means of a pressurized return line back to the tank, and an electric fuel pump, to evacuate any vapor pressure that might result in vapor lock when a hot start under a hot condition MIGHT be created. By locating this above the engine, at the highest point in the fuel lines, and running the electric fuel pump, the vapor lock is avoided.

4. We only remove the fuel pump fuse with first cold start of the day, because we are on the ground, not in the air, the motor is cold, the oil pressure will be high, and the rpms once started will be low, so loss of any fuel pressure or fuel starvation is a non issue, since the motor is not running at or near full load or throttle. The load on the battery in these conditions, low temps, high resistance, and chemically speaking lowest provided voltage from the battery, are like a double or triple whammy on the peak capacity in amps on the battery, that it is capable of providing.

That's my thought process... the only time we blow fuses is first cold start of the day, so that's the only time the fuel pump fuse is temporarily removed, motor started up, voltage comes up, then reinstalled. We've never blown a fuse on reinstallation of the fuse into the fuse panel, yet. YMMV, this is the procedure we've been using, use it at your own risk and apply your own logic.
 
This thread has gone off the track. Niner is happy with his logic -- so be it.

When we were losing fuel pump fuses when the Earth X batteries kept dying, the fuel pump being defective was a consideration for blown fuses as part of a phantom electrical draw on the battery, causing it to lose charge.

Now, I just look at it as a possible indication that your battery is dying or dead, so, in a sense it is related to the Original Post, as perhaps a sign your battery is shot.
 
1. We've lost a few 5 amp fuses. Part of the routine now is that we do CCiGARR


3. Van's saw fit, in their engine specs, to add a bunch of fuel hoses, a means of a pressurized return line back to the tank, and an electric fuel pump, to evacuate any vapor pressure that might result in vapor lock when a hot start under a hot condition MIGHT be created. By locating this above the engine, at the highest point in the fuel lines, and running the electric fuel pump, the vapor lock is avoided.

The configuration of the fuel system (with the exception of the electric pump location and the decision to have it operating all the time) was not a Van's design decision, but was Rotax. If you look at the install documentation published by Rotax, it is very specific regarding the required configuration of the fuel system (and many other aspects of the engine installation

4. We only remove the fuel pump fuse with first cold start of the day

If this is because of repeated instances of the fuse blowing, then there is an underlying problem that has not been resolved. This is totally unnecessary on an RV-12 that has a good battery and properly functioning systems
 
I turn on the master switch, listen to be sure the electric fuel pump is running and check fuel pressure.
Start the engine and look for an increase in fuel pressure to be sure the engine fuel pump is running.

Excellent. My Before Takeoff Checklist has line item for electric fuel pump and a second line item for electric pump + mechanical pump. In addition to listening for the electric fuel pump I put my hand on the fuel shutoff valve and feel for the electric fuel pump "pulse".

Seat Belts – Latched
Controls – Free
Fuel Valve – On
Master Switch – On
Check Electric Fuel Pump Pressure – 2.2 psi Min
Avionics Switch – On
Fuel Level Gauge – Matches Fuel Tank Dip Stick
Engine Start
Oil Pressure – Check 12 psi Within 10 Seconds
Choke – Off
Ammeter – Charging
Fuel Pressure Engine Running – Check 5.0 psi Min
Warm Engine – 2500 RPM Until Oil Temp 122F
Fuses – Check
Comm Radio – Set Frequencies
Transponder – Set for ALT
Altimeter – Set
Mag Check 4000 RPM – 300 RPM Drop Allowable
Ignition – Both On
Flaps – First Notch
Elevator Trim – Set for Takeoff
All Engine Instruments – Green Arc
Canopy – Latched for Takeoff
 
This is my post and I am OK with it going off topic......so with that being said;

I have blown the pump fuse on several occasions, and it is low voltage that causes more amp draw to blow it. My solution has been Dynon on > all switches off > fuel pump fuse in > start engine > turn on avionics, lights, autopilot, etc. I have not blown a fuse since doing it that way. I believe keeping all the other power users off during the start keeps the voltage drop to a minimum.

question;
Those of you that have to listen / touch to know if the fuel pump is running, what pump do you have, how is it mounted? Mine is so LOUD the guy 3 hangars down can hear it. I sometimes pull the fuse out of embarrassment and to avoid questions.
 
Last edited:
Low battery voltage does increase amp draw so I guess fuses can blow. Low battery voltage will also cause slow engine cranking and kickback with the old CD ignition without spark retard... that's bad for the one-way roller bearings that are part of the starter mechanism.

Best to keep battery at higher charge level and not have above mentioned problems. I have Odyssey OBC-6A charger always connected in the hanger. Been doing it for years. Charger is not a "Float" or "Battery Tender". The Odyssey only works as needed and has a secondary benefit of de-sulfating on a pre-programmed once/month schedule. Makes everything hunky-dory...
 
If this is because of repeated instances of the fuse blowing, then there is an underlying problem that has not been resolved. This is totally unnecessary on an RV-12 that has a good battery and properly functioning systems


Fuses were only blowing when battery tested out bad, out of the airplane, on the bench. Owner was lucky recipient of 2 bad batteries in a row, from Spruce Aircraft.

A pig tail with Anderson Power Poles has been attached to the battery terminals, with access through the oil check port in the cowling. Voltage is checked at completion of flying, and again before going flying 1 to 2x per week. 13.13 to 13.20v is what is seen on battery after flying, with a surface charge showing. 15 to 20C battery temp with a week between flights shows 12.83 to 12.86V normally showing, consistently, since middle of Sept 2019, when battery was changed out for 3rd time in a year. Original battery lasted since Jan 2016 to Dec 2018.
 
This is my post and I am OK with it going off topic......so with that being said;

I have blown the pump fuse on several occasions, and it is low voltage that causes more amp draw to blow it. My solution has been Dynon on > all switches off > fuel pump fuse in > start engine > turn on avionics, lights, autopilot, etc. I have not blown a fuse since doing it that way. I believe keeping all the other power users off during the start keeps the voltage drop to a minimum.

question;
Those of you that have to listen / touch to know if the fuel pump is running, what pump do you have, how is it mounted? Mine is so LOUD the guy 3 hangars down can hear it. I sometimes pull the fuse out of embarrassment and to avoid questions.

Same situation here, electric fuel pump sounds like a mini jackhammer inside the cockpit, all the time.
 
Fuses were only blowing when battery tested out bad, out of the airplane, on the bench. Owner was lucky recipient of 2 bad batteries in a row, from Spruce Aircraft.

A pig tail with Anderson Power Poles has been attached to the battery terminals, with access through the oil check port in the cowling. Voltage is checked at completion of flying, and again before going flying 1 to 2x per week. 13.13 to 13.20v is what is seen on battery after flying, with a surface charge showing. 15 to 20C battery temp with a week between flights shows 12.83 to 12.86V normally showing, consistently, since middle of Sept 2019, when battery was changed out for 3rd time in a year. Original battery lasted since Jan 2016 to Dec 2018.

Sounds like everything is back to normal.
Then why continue to remove the fuel pump fuse during every engine start? That just adds risk of failing the fuse sockets on the AV-50001.
 
Earth-x in RV-12 with uls

I installed one last summer. I also installed a Silent Hektik VR, the one that Van's recommends with voltage step up. I did new W/B calculations and the only time it can go out the back is with a pilot along and 50 pounds of weight in the back. So when I fly to Oshkosh with my luggage and camping equipment, I put the heaviest item on the floor in front of the passenger, then I put a heavy duffle bag in he passenger seat, and lighter things in the back. That keeps me within gross takeoff weight and w/b.

The advantage of the this battery is that it has power management system and if over voltage is coming to the battery, it will stop accepting it. The advantage of the SK VR is twofold,l it has more capacity than the ducatti and it has over voltage protection. It the voltage goes high, it will shut down. But the VR has more capacity than the alternator, so you can't load the system up and not expect problems.

For me the less weight was not a factor in buying it. I have had no problems with it since I installed it.
 
Back
Top