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  Topic Review (Newest First)
12-29-2016 09:09 AM
OJABA I just do not feel they are performing as they should. For the price I expected these things to light up the neighborhood. They are bright but not what I expected. Maybe expectations just too high.
12-28-2016 06:22 PM
Jerry Bransford
Originally Posted by digdug18 View Post
What are the HID's doing or not doing that you think you need a larger alternator? Are you getting flickering or coming on slowly or something along those lines?
HID and LED lights draw less amperage than the incandescent bulbs do that our older Jeeps originally came with. Going to newer technology lighting reduces the amperage draw so if there's one thing that is not needed for them it is a larger alternator.
12-28-2016 02:09 PM
digdug18 What are the HID's doing or not doing that you think you need a larger alternator? Are you getting flickering or coming on slowly or something along those lines?
12-20-2016 02:52 PM
Jerry Bransford Just go for a good AGM (absorbed glass mat) style battery with a good 700 to 800 CCA capacity which is key for things like winching and lights. No alternator can keep up with the >400 amperes a winch can draw, it's only the battery that can provide that kind of current. Most battery shops carry AGM batteries which are far more rugged and suitable for the bumpy trails that can take out a conventional liquid acid battery. Avoid Optima's AGM batteries which give too many problems after Optima was bought by Johnson Controls who moved Optima's entire battery manufacturing center to Mexico.

A second battery is not necessary. Some like to think they are but they're only useful in rare circumstances. Not to mention most of the dual-battery connection schemes give problems and you end up with a dead reserve battery when you expect it to be fully charged and ready to use. I've actually had to winch my Jeep off the trail twice now when I couldn't start the engine (blown steering box seal and bad ignition coil) and my single AGM battery did it it just fine. It started the engine after I fixed the problem that prevented me from starting the engine without need of a jump start.
12-20-2016 06:54 AM
wingless Very nice Jeep!

Welcome to the forum!

If possible, properly adding an additional identical battery, w/ matching brand, P/N and date code will double the reserve, for things like normal low duty cycle winch usage.

A larger output generator provides more supply when the engine is operated above idle, like 1,500 rpm and up. That is useful for ear bleeding stereo amplification, pulling 100A or more.

Measure the voltage at the lamp connector during operation and also measure the voltage at the battery under the same operating conditions. Those voltages should be the same, less than 1V difference. It is better to have them less than 0.5V difference. With the engine at a high idle, the battery voltage should be about 13.8 VDC, higher at lower ambient temperatures.
12-19-2016 03:12 PM
OJABA Any brands recommended over others? Also just one or Two?
12-19-2016 03:08 PM
OldJackTheJeep Up grade your battery first.
12-19-2016 02:10 PM
Alternator Upgrade

Hey everyone, I'm pretty new to the "build it to last" world with jeeps. I'm taking my time with this one and trying to do it right, so it can be used as a jeep should be! Anyway, I am looking to run a pretty good winch and all the lights and stereo equipment and I can fit into this thing because mainly all that stuff exists! Within reason of course, I want the rig to look turn heads without people asking why would someone do that. That being said, I have a pretty stock setup on my '81 CJ7, Inline 6 all original everything, runs like a champ after a couple months of chasing noises. I was wondering what people have done with their alternators, is this an upgrade I should focus on? I just installed KC HID lights and do not feel they are performing as they well as they can, so I am asking the Pros. What should I do here? Thanks for your help!

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