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Old 05-10-2016, 11:19 AM
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funola funola is offline
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Quote:
Originally Posted by HuskyMan View Post
The yellowish stuff on the top of the battery is residual from spraying the terminals with battery cleaner (picture enclosed). BTW, my local car parts place is going to run an exhaustive test on the battery to determine if there are shorted/open cells, etc. Their battery testing machine is a lot better than my simple two buck battery hydrometer. I'll report back with the results of the test.

Is it just me or has the price of batteries gone UP?
FYI, your $2 battery hydrometer can do what the expensive battery testing machines cannot do.... specific gravity, which indicates state of charge of each cell. If you fully charged the battery, each cell should show the same full charge specific gravity. It is extremely accurate. What did your $2 tester show? If it showed one cell with low specific gravity, don't waste your time doing further tests, buy a new battery.

I bought an Interstate H8 AGM "take off" from an Interstate warehouse for $40 last summer http://www.interstatebatteries.com/p/mt5-49-h8-audi-a6-2015-33-50-54-55-56-58-v6-3-0l?dsNav=N~21-2147384903 . It's working fine. This "take off" supposedly came from a Mercedes dealer and was taken off a new car and returned to Interstate for whatever reasons. Interstate supplies Mercedes with batteries in the US. Per the manager of the warehouse, all the "take offs" were tested and a percentage of them have nothing wrong with them and sold at their warehouse at a discount. The Mercedes labels were removed and an "Econo Power" label put on before sale.

If you do get an AGM battery, your $2 hydrometer cannot be used since it is a sealed battery (with a pin hole vent).
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