my white eddie, I see a lot of electrical terminology being used incorrectly in this thread, which may hamper some of your efforts. Most auto/light truck batteries have a capacity of 50-70 Ah (some people refer to this as amp-hours). This number indicates how much energy can be stored in your battery and indicates something completely different than the CCA rating. Think of Ah as the size of the electrical “fuel tank”.
The CCA rating of the battery for your vehicle is probably in the 600-800 range. This number indicates a battery's ability to delivery a large amount of current in a short time. Think of this as the gallons/minute your fuel pump can flow.
The time it takes to charge your battery and the time your battery can provide power is most strongly related to the energy storage capacity (Ah) of the battery, not the CCA rating.
I would encourage you to watch
this video, which explains how to measure parasitic draw and then re-measure your draw. If you really had an 8.2-amp draw, your battery would not be starting your vehicle. Doing some simple math, an 8.2-amp draw would be discharging your battery at a rate of 196.8 amps (8.2 x 24 hours) per day. If you have a 50 Ah battery (no one is using a 650 Ah battery), an 8.2-amp draw would probably drain it flat in about six hours.
I'm obviously a battery guy and not an alternator guy, but I think the advice relating to a review of your wiring is sound. Since I didn't see anyone else suggest this, I can also share that one of my friends who works for an alternator manufacturer has told me many of the "bad" alternators returned to them are the result of slipping belts.
The number one reason they see for premature alternator failure, including no output, is a slipping v-belt. The following is quoted directly from their tech bulletin:
In the good old days when all we neede was a 40-60 amp alternator, slipping belts were not a common problem. Now that we need 100 amps and up, it has become a real issue. The higher the amperage, the more resistance an alternator has and it takes more power to turn the pulley. Therefore, the belt has to be tighter to prevent slippage.
Signs of belt slippage- Little or no output, discharged battery, pulley extremely hot and starting to discolor, rust on the alternator shaft, belt dust collecting on the fan and front of alternator housing, belt sticking to pulley, glazed or cracked belt, belt riding too deep in the pulley groove, bearing noise. Note: Most of the time, the alternator belt doesn't make a squealing noise when slipping.
You think your belt is tight enough, but is it? Here's a simple and fool-proof way to check- Place a socket and pull handle on the alternator pulley nut and turn clockwise. Does the pulley slip? If so, the belt isn't tight enough and will slip while the engine is running. When checking belt tension this way, it should try to turn the engine and will not slip at all.
Jim McIlvaine
eCare Manager, OPTIMA Batteries, Inc.
www.pinterest.com/optimabatteries