Battery ?

[wilbur]

If a Bat test good on a load test can it still have a bad cell. The reason I ask is my PD55 looses power after about 3 to 4 hrs. Before it would run 5 to 6, but I had an extra 200# in the boat. I never used the Bat guage on the motor til today. The Fluke meter showed 13.07 volts. I checked the guage and it said 3/4 charge. Any suggestions? Oh the 13.07 was after the load test for 10 sec.

[SeaRay]

Wilbur,
Back in the dark ages of the 70's I had a cell tester to test my battery. It measured the specific gravity of each cell and will tell you if you have a bad or weak cell. I have not used one in a long time, but they are cheap and easy to use. The tester comes with a chart and has different colord beads in it and depending on the condition of the battery all some or none of the beads will float. If none float when you fill it you got a dead cell. I speck you can get one at Walmart or a auto store for less than $10.
Good luck
SeaRay
PS
Found this one at Sears for $5.67 Victor Automotive Products Victor Automotive Products V644 Battery Tester - Tools - Mechanics & Auto Tools - Diagnostic Tools & Testers

[FAADAN]

If you have 13 volts, you haven't lost a cell. Extra weight in the boat will add load to the motor. I wouldn't blame the battery.

[wilbur]

If you have 13 volts, you haven't lost a cell. Extra weight in the boat will add load to the motor. I wouldn't blame the battery.

Thanks thats kinda what I was thinkin.

[crappielimits]

Could have a bad connection or lower unit problem. You haven't by chance added the ipilot recently?

[Slab Junkie]

13 volts is for sure a good battery but maybe it doesn't have enough capacity. What group size is it?

[Cray]

Wilbur you should not lose that much run time even if you added that weight. It sounds like you have a good load test. One thing you need to chech though is when it has been charging for awhile use the feel test. Touch it with your hand it should be kinda warm ok but if it feels much warmer than just warm you have a bad cell. Not all bad cells will show up on a load test at first but if you keep discharging and charging it will get worse. A lot of what is normally refered to as a bad cell is a shorted cell either a plate breaks loose or warps until it touches another plate inside that cell. Also go back and pull all connections and check them for clean and tight even at the motor. A loose connection creates heat and raises resistance which draws more amps per hour.

[skeetbum]

All good info so far. Catfan in KY makes a living with batteries, I look to him for the final word on this stuff. Very helpful and knowledgeable.

[wilbur]

13 volts is for sure a good battery but maybe it doesn't have enough capacity. What group size is it?

Its a 27 Duralst. the biggest that would fit. I have two in parralel

[wilbur]

C,mon Cat fan lets here your opinion.