Left ignition key ON in FX-3

[viator092]

Finally happened. Hooked up the Genius 5 to charge up the battery for about 5 hours. Tried to start forgetting I had left the key ON earlier so don't remember the start voltage. Prop swung slowly a few turns but no start. Got out my NOCO GB40 Booster. Nothing. Yeah it was charged up. Got to reading the instructions to make sure I didn't bone up something. Says it's for jumping lead acid batteries only. Are folks using GB40 for AGM and LiFiPo jumps?

Hooked it back up to the Genius 5. Hoping tomorrow it will start.

 

[ve6yeq]

In addition to master off, IBBS off and always removing the key when I secure my EX-3, I also pull both the ignition breakers just to make sure. I have noticed that the Garmin G5 internal battery appears to slowly drain but the main EarthX seems to be fine even after 6 weeks of bad weather over the winter.

I also use a Optimate TM-275 V2 in power supply mode when I am updating Garmin firmware and databases so maybe that slowly charges things enough that I don't see any discharge issues.

 

[Waldom]

If you know your engine and have been properly taught how to do it, did you consider hand propping in order to complete your flight?

 

[Neal]

I almost left the key on, from that point forward I always remove the key. I usually attach it to my magsafe phone mount but it can go multiple places such as the dash, fuel selector, a G3X knob, etc.

I have the GB40 but have not used it yet, hope not to, hope it works and assume it should as regardless of the battery it's still 12V. I used the XP1 once in the past but that was on the SBS-J16 battery.

As to your charger, it sounds like you have the EarthX? If so, you should be using the Optimate charger and I use a pigtail as it can take a higher amp charge than what you can push through the 12V port under the panel. I've blown the fuse for that 12V receptacle twice and I wonder if yours is blown and not charging now? You have to lift the seat and check the two 5A blade fuses to make sure they are not blown. But do yourself a favor and add pigtails for the GB40 and Optimate. Not the funnest install but when done it's great.

For the EX/FX-3 owners, I have two black suede dash mats left if interested. Click here for details. (SOLD OUT)

@Waldom I saw a YouTube video of Kevin Quinn hand propping a FX-3 and it took around 80 attempts to get the start. May have been some factors as to why it didn't start earlier but hope to never have to do that.

Optimate info in the thread below:

EarthX battery for Experimental Aircraft

I spoke with the EarthX folks at Oshkosh (2023) about the venting requirement for an EarthX battery. CubCrafters runs a vent tube from the battery box to the actual vent(s) on the battery to outside. For someone like me that has the "upgraded" SBS-J16 starter battery we don't have a vent line...

flightinfo.com

 

[Waldom]

If this young lady knew the start sequence on the FX-3 as well as she does on this airplane, It would start on the first pull as this engine did.

 

[Neal]

 

[Waldom]

The carburetor was flooded on the first hand propping attempt. The procedure to fix that would be to double check the ignition switch off and set the throttle full open, then pulled the prop through 16 blades. Bring the throttle back to the "cracked" position (not closed as the pilot in the video had it). switch the mag to whatever one or both has the impulse coupling or Surefire ignition and it should start.

As I said, you have to know your engine.

Sorry I can't figure out how to post my video. It showed a young lady starting a PA-11 from behind the propeller one handed on the first pull.

 

[Neal]

The FX-3 engine is fuel injected, no carb. But I agree, there are probably a number of factors that are not ideal from flooding (over priming) and who knows what else. Throttle position, mixture, etc. etc. But I hope to not have to try it.

 

[Waldom]

The FX-3 engine is fuel injected,

No wonder Carbon Cub owners are so interested in start sticks. I have started fuel injected engines by hand propping, but they are not as easy to start as carbureted engines by using that method.

 

[lrobichaux]

As to your charger, it sounds like you have the EarthX? If so, you should be using the Optimate charger and I use a pigtail as it can take a higher amp charge than what you can push through the 12V port under the panel. I've blown the fuse for that 12V receptacle twice and I wonder if yours is blown and not charging now? You have to lift the seat and check the two 5A blade fuses to make sure they are not blown. But do yourself a favor and add pigtails for the GB40 and Optimate. Not the funnest install but when done it's great.

I too have the EarthX battery and bit the bullet to purchase the proper Optimate charger which I connect with the pigtail connector. Expensive, but it's what's needed for the EarthX smart battery.