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lr172

Well Known Member
My 6A is almost ready for Phase I. I have an Odyssey 680 knock off from ACS (powerSonic). A couple of weeks ago I cranked the engine without a set of plugs to prime the oil system. I had no issues cranking, but I also didn't have any compression to resist the cranking. Afterwards, I put a standard (not automatic) charger on it and forgot about it and it sat charging overnight.:mad:

Today I went to start the engine for the first time and I don't have enough energy to get the blade to barely make one revolution. The starter is an old Remy, but newly rebuilt. I have 4 ga. wire to the starter. I am pretty sure it is battery issue. It won't take much of a charge eventhough the voltage is down to 12.6 volts. I can also see the volts drop to 9 when cranking. Does anyone have experience with these batteries? Are they easy to damage with over-charging?

Thanks for any guidance you can provide.

EDIT: I just tried again for a few cranks and one half of the starter gets pretty warm. The other half is cool (top half vs. bottom half). The starter stayed cool when I did the cranking without the plugs. Not sure if that means much, but is making me concerned about the starter.

Larry
 
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Don't know how much cranking you did without the plugs in, but a normal start (pushing through compression strokes) uses maybe 3-5% of a starting battery's capacity, so it might not have needed charging. Cranking without plugs also won't stress your wiring and connections, since there isn't much current demand.Did you notice any moisture around the 'valve' (emergency pressure relief port)?

12.6 volts would normally be considered fully charged for a 12v battery ('14 volt' system). 9 volts output under starting load doesn't sound that bad, either.

Have you measured voltage while cranking, with the meter negative probe directly on the battery negative terminal, and the meter positive probe directly on the positive terminal of the starter? Compare that measurement with the cranking voltage directly across the battery terminals. This will tell you how much voltage drop you have in your wiring and connections.

If you see a significant difference between the two voltages, then you probably have 'issues' with high resistance connections somewhere between the battery and starter (can be on the positive side, the negative (ground) side, or both).

Last, what's the AH rating of the Powersonic? Some of the 'knockoff' batteries have the same AH rating as the 680, but may not have as great a 'cold cranking amps' rating. I solved that issue for myself by going to a 20 or 22 AH rating battery (still same form factor as 680) and equal cold cranking amps, with greater total reserve capacity). And still a lot cheaper.

Charlie
 
I don't think I would consider Powersonic a "knock-off" battery. They have been building batteries for over 45 years and have an excellent reputation.

I've been using them of over 22 years and never had a problem with one. They typically last 4-7 years in my RV-6.
 
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To your question - there is no way to truly know without more information. Charge the battery and try again. Then ensure you diagnose it like any other starting issue - connections, fasteners, etc for voltage drop.

The windings in the starter are not the full length, so it is not unusual for only part of it to be heated. Permeant magnet starters have a lot higher torque-per-amp as the battery only creates part of the magnetic field. That does not mean your starter is bad.

Good luck in the process.

4 gage seems a bit small, recheck your needs there. If it is part of the issue then a higher than normal voltage drop will be measured during starting.
 
Do you have a ground strap that runs from the engine back to the firewall and then to the battery's negative terminal?
 
Thanks for all of the suggestions here. Turns out it was the starter. Whoever rebuilt it should really retire. Everything was wrong. I took apart the outer parts a year ago and they re-installed the Bendix completely wrong, like every part that came out. Last night I completely tore it down and the rebuilder cracked one of the two main feeds from the post to the outer windings. So, it was only getting power to half the windings. Took me quite a while to get enough heat in there to get it soldered. Cranks over quite nicely now.

Not sure how long it will hold, so will probably post a WTB for an old style starter.

Larry
 
Mel said:
I don't think I would consider Powersonic a "knock-off" battery. They have been building batteries for over 45 years and have an excellent reputation.

I've been using them of over 22 years and never had a problem with one. They typically last 4-7 years in my RV-6.
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Good to know. It was quite a bit cheaper than the Odyssey, so I was worried.

Larry
 
Larry, not sure why you want to stay with an old style starter--------unless your engine will not accept a newer style one.

New starters are usually more efficient and lighter in weight.
 
Mike S said:
Larry, not sure why you want to stay with an old style starter--------unless your engine will not accept a newer style one.

New starters are usually more efficient and lighter in weight.
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I appreciate the input. I have been warned that the 6A with wood or composite prop and O-320 tends to be tail heavy. I met a guy with a 6 and wood prop that told me the best mod he made was putting on a heavy starter as it balanced out better. This starter came with my engine core (I rebuilt it) and I figured I would start with the heavy unit and see how my W&B works out. I can replace with a lightweight starter if I end up nose heavy, but I don't think that I will. I also have a steel crush plate that I can add if I want more weight up there.

Larry
 
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