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-   -   What killed this PC680? (https://vansairforce.net/community/showthread.php?t=99810)

bruceh 02-01-2017 10:13 PM

Interesting thread to read. I too have recently had my PC680 Odyssey battery fail to start the airplane 3 times now. The first time, I hadn't flown for several weeks, so I put it on the Ultimizer charger which topped it off and I got back in the air. January 1st we had planned to fly out to Lake Havasu for the RV New Year's day fly out, but it was cold (for San Diego) and the battery ran down pretty quick when I tried to get the engine started. I put the charger on and thought I should just plan to keep the trickle charger on during the colder months. Did a couple of flights after that with no problem. Yesterday it was warm and gorgeous here and after not flying for a week, I was ready for some air time. I did my pre-flight quickly and by the time I was ready to start the engine the battery was down to 11.9V (normally it would be sitting around 12.4V). It barely spun the prop twice then pooped out. The battery had been on the trickle charger, so I was wondering if the battery was just beyond recharging. I've ordered a new one. The current one was bought over 6 years ago during the build and has been flown 360 hours in the last (almost) 3 years. I normally did NOT keep the battery on the trickle charger unless I was running the electrical stuff on the ground. The alternator charges the battery at 14.5V in normal operation. I will see if I can restore this battery with the procedure recommended, but for my personal comfort, the new replacement will go in the airplane. Thankfully, I never got stranded anywhere!

rleffler 02-02-2017 06:02 AM

Bruce,

Are you using an older Odyssey charger or one of the new ones that came out this year?

I've damaged my old one and purchased one of the new ones. The charging process seems significant different between the two. I've asked Odyssey a couple times to explain what changed, but haven't found the right person that actually new the answer. The new one shows more phases of the charging process than the old one did.

I have a pair of 680s in my RV-10. They are going on almost four years old now. I typically only put them on the charger when I'm in the hangar working on something. Although at the moment, I have it hooked up to my cell phone remote to ensure that they are topped off in this cold weather.

Some folks with dual batteries swap one out each year at the conditional inspection. I guess I'm still too frugal to do that. I do have the benefit of being able to put both in parallel to get a few extra amps for cold weather starts.

bob


Quote:

Originally Posted by bruceh (Post 1146800)
Interesting thread to read. I too have recently had my PC680 Odyssey battery fail to start the airplane 3 times now. The first time, I hadn't flown for several weeks, so I put it on the Ultimizer charger which topped it off and I got back in the air. January 1st we had planned to fly out to Lake Havasu for the RV New Year's day fly out, but it was cold (for San Diego) and the battery ran down pretty quick when I tried to get the engine started. I put the charger on and thought I should just plan to keep the trickle charger on during the colder months. Did a couple of flights after that with no problem. Yesterday it was warm and gorgeous here and after not flying for a week, I was ready for some air time. I did my pre-flight quickly and by the time I was ready to start the engine the battery was down to 11.9V (normally it would be sitting around 12.4V). It barely spun the prop twice then pooped out. The battery had been on the trickle charger, so I was wondering if the battery was just beyond recharging. I've ordered a new one. The current one was bought over 6 years ago during the build and has been flown 360 hours in the last (almost) 3 years. I normally did NOT keep the battery on the trickle charger unless I was running the electrical stuff on the ground. The alternator charges the battery at 14.5V in normal operation. I will see if I can restore this battery with the procedure recommended, but for my personal comfort, the new replacement will go in the airplane. Thankfully, I never got stranded anywhere!


bruceh 02-02-2017 01:22 PM

Quote:

Originally Posted by rleffler (Post 1146827)
Bruce,

Are you using an older Odyssey charger or one of the new ones that came out this year?

I bought the charger around the time I bought the battery, so it is about 6 years old.

Tracer 10 02-02-2017 02:55 PM

Charge or not to charge.
 
2 Batteries in 16 years. Only put on charger if haven't flown in 6 weeks. And only for a couple hours. --Usually fly once a week.

rv7charlie 02-02-2017 05:41 PM

I've used brand X (best price at the time) SLA batteries for as long as they've been available. I haven't been able to fly much at all for years (typically <10 hrs a year), and only charge on the ground if the plane won't start. My current model is a 24 AH (slightly larger dimensions than a PC680) that's been in the plane since 2012. A few months ago, after a couple of failure-to-start events, I ordered a new battery. When I opened the cowl & removed the terminals, I found corrosion on the cable lugs (not the battery posts). Cleaned it up, charged the battery, and everything's been fine since.

Point of the story is that if you have less than ideal conductivity throughout the charging path, it can not only interfere with starting, it can prevent proper charging as well. The regulator sees voltage either at the alternator, or at some point that's still well upstream of the battery. If there's a high resistance joint anywhere downstream, or anywhere in the negative side, it can prevent proper charging and shortened battery life.

Charlie

bruceh 02-03-2017 11:37 AM

New PC680 battery arrived yesterday, so I went out and installed it.
Man, what a difference. I don't think my prop has ever been spun that quickly by the starter! I think the old battery was definitely compromised in some way.

mrreddick 02-03-2017 02:23 PM

Odyssey Batteries
 
I bought a PC680 at Airventure 2015, installed it in my 6A early September 2015. I kept it on trickle charge over the winter since I was only able to fly a couple times a month. Almost exactly a year later it died. After charging it was holding 11.3 volts. Ordered a new PC680 and reinstalled my 6 year old one that was being used as a paperweight until it arrived. Spun the prop and started really quick. When the new one arrived in late November 2016 it went in use. Now, less than 3 months later, the new PC680 is indicating 10.7 volts after charging. Contacted the seller about warranty and haven't received a reply. 😡

rv7charlie 02-03-2017 02:39 PM

Quote:

Originally Posted by mrreddick (Post 1147293)
I bought a PC680 at Airventure 2015, installed it in my 6A early September 2015. I kept it on trickle charge over the winter since I was only able to fly a couple times a month. Almost exactly a year later it died. After charging it was holding 11.3 volts. Ordered a new PC680 and reinstalled my 6 year old one that was being used as a paperweight until it arrived. Spun the prop and started really quick. When the new one arrived in late November 2016 it went in use. Now, less than 3 months later, the new PC680 is indicating 10.7 volts after charging. Contacted the seller about warranty and haven't received a reply. 😡

You can fix your problem by leaving your charger at your relative's house, 3 towns over. ;-)
That way it'll be really inconvenient to throw the battery on the charger, and you won't be overcharging it constantly.

SLA batteries will go many months without self-discharge. (See my earlier post.)

Charlie

Sam Buchanan 02-03-2017 03:10 PM

Quote:

Originally Posted by mrreddick (Post 1147293)
I bought a PC680 at Airventure 2015, installed it in my 6A early September 2015. I kept it on trickle charge over the winter since I was only able to fly a couple times a month. Almost exactly a year later it died. After charging it was holding 11.3 volts. Ordered a new PC680 and reinstalled my 6 year old one that was being used as a paperweight until it arrived. Spun the prop and started really quick. When the new one arrived in late November 2016 it went in use. Now, less than 3 months later, the new PC680 is indicating 10.7 volts after charging. Contacted the seller about warranty and haven't received a reply. ��

There is no need to charge a PC680 that flies twice a month! That is plenty of activity to keep it hot all the time unless you have a heavy keep-alive load.

You are killing your battery by using the trickle charger......

mrreddick 02-03-2017 03:30 PM

Dead Odyssey
 
Quote:

Originally Posted by Sam Buchanan (Post 1147304)
There is no need to charge a PC680 that flies twice a month! That is plenty of activity to keep it hot all the time unless you have a heavy keep-alive load.

You are killing your battery by using the trickle charger......

thanks for the quick responses but, the latest PC680 didn't go on a trickle charger once I installed it. I flew maybe 10 hours with it and then it suddenly wouldn't spin the prop. That's when I put it on a charger and found out it was resting at 10.68 and wouldn't charge up past 11.3 volts. I don't think I killed it by the very short charge to check its' condition. My old six year old PC680 is back in the plane and did fine today at barely over 40 degrees outside. No cranking issues, only with the two latest PC680's purchased within the last 18 months.


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