If the jump battery started the engine fine, why do we think the starter is bad?
Greg
Battery problem
- Thread starter Sailnobroblem
- Start date
Greg
Good point. There are a few seemingly contradictory symptoms going on here.
I presume it was connected to some charge source at that time? Have you charged the battery via a shore charger at all? What is its resting (not during charge or use) voltage? Is it possible that the good battery was partially discharged and still hasn't been brought back to a state where it can start the engine itself?
I have both batteries connected to a Guest on board battery charger. Yesterday I checked the one good battery with nothing connected posts removed and it read 12.78 volts, reconnected it read the same. I bypassed the switch no movement, not even the telltale tick sound. I installed a fresh battery to replace the bad one set the switch to both, the starter was spinning but not engaging, but seemed sluggish.
At this point I am just going to give Ken at Moyer marine a call. He was a huge help in the past.
I also tried to charge the original bad battery with no luck. I took a continuity test across the posts which indicated a short.
I want to thank you both for your help.
I also tried to charge the original bad battery with no luck. I took a continuity test across the posts which indicated a short.
I want to thank you both for your help.
I’ve had similar problems. One possible answer is a bad alternator- sometimes when they fail, they drain the battery to which it is attached. If you can get it started check it’s output - you may need a bigger DVM to measure more than 10 amps.
I would look for a short in the starter circuit - of course the battery will go to 0 volts if left connected to a load and no charging, what would stop it? Did you measure the voltage of the good battery while wired as a start battery? I'm guessing it was not at 13+ volts then and that's why it wouldn't start the engine. Also check the voltage at the battery and at the starter when the start switch is engaged. A bad battery may run house loads and take a charge, but not have enough energy to start an engine, so would a bad connection.
Just got back from the boat put in two new batteries and she started right up. so the batteries were the problem, the thing is something made those batteries die. leaning towards the guest battery charger. Not sure I can check it any particular way. Anyway I'll keep checking everything else don't want to keep buying batteries every couple of weeks. again thank you everyone for all your advice and suggestions.
Glad it's working. Can you now start it with either battery selected individually? I'd take the old "good" battery to an auto parts store and have it load tested just for curiosity. A load test won't tell you the remaining capacity of the battery for deep cycle use, but it will tell you if it still has the cranking amps to start an engine.
What do your voltages look like when you're charging, and are you boiling off excessive electrolyte? The voltage should go into the mid 14's for a little while when charging discharged batteries, then settle somewhere in the 13.2 range. If it's doing that then the charger shouldn't be too off.
Continuity test across a battery? Doesn't sound like a useful test to me. If battery is dead, and it shows a short, well it would. Batteries are supposed to e very low resistance, that's why the voltage doesn't drop when you apply a load. Test cross a charged battery? Smoke the meter.
Now, continuity, or more useful, resistance from end to end on cables, that's useful. Across contacts on the switch too. Leave the meter clipped to the cables and watch to see if the reading changes as u shake the cable. Feel for any hard spots that don't flex as easily... That's corrosion increasing the resistance...
Yes, I know u said the new batts seem to have solved it, but it's still possible u have only fixed the symptm, not the cause... And she will let u know at the worst possible moment...
Had a car once thatwouldnt turn over at all once in a while... Until I kicked the tire.. finally found the main chassis ground wire corroded and intermittent under the engine somewhere.. not the only car of mine that had an intermittent wire make the thing act like it was possessed
Now, continuity, or more useful, resistance from end to end on cables, that's useful. Across contacts on the switch too. Leave the meter clipped to the cables and watch to see if the reading changes as u shake the cable. Feel for any hard spots that don't flex as easily... That's corrosion increasing the resistance...
Yes, I know u said the new batts seem to have solved it, but it's still possible u have only fixed the symptm, not the cause... And she will let u know at the worst possible moment...
Had a car once thatwouldnt turn over at all once in a while... Until I kicked the tire.. finally found the main chassis ground wire corroded and intermittent under the engine somewhere.. not the only car of mine that had an intermittent wire make the thing act like it was possessed
If these batteries were wired in parallel and one was dieing it most likely did some damage to the “good” one. Are these true deep cycle batteries and were they the same age. Maybe put your meter on the battery while starting and see what happens.... you may have another bad battery.
Good luck
Greg
Good luck
Greg
Both batteries were deep cycle, they were from 4/12 installed 6/12, so I guess I can't complain. Checked the grounds all are okay still want to check my quest battery charger. It's a maintenance charger. Kept everything good for 7 years.