Alternators and upgrading

[Petescj]

I'm hoping this thread goes the way the mechanical fan thread did , very informative. My engine is currently out of the Cj and I'm out to get more knowledge about it s components. I looked up the Auto Zone part number off my alternator and it says 78 amps under a section called notes but under amps it says 95. Why two different ratings? Mine is from a 87 with the part number DL 7273-9. I had heard the Yj alternator was an upgrade over the Cj and from what information I've found that's true.

So when do upgrades become necessary? I'm planning on adding some upgraded lights a stereo and a CB to my Cj. I already have a winch but that's about it. When is it time to look into upgrades? Is there really a need to spend $300 on an alternator? My engine complete was only $100 more than that.

 

[Posi]

There is no need to spend big money on an alternator in most cases the 12si is plenty for most and has improved cooling over the 10si. However, on the trail the SI series do not work well at idle, or just off idle. Trail use I would go with a CS series from a late 80's caddy, has 96 amps and charges nicely at low rpms. I spent $10 at the boneyard for my alternator.

Some reading to get you started.

Catalog


Delco Alternator Upgrades With Q & A

 

[Posi]

For those without a boneyard nearby, or would rather buy new with a warranty you can get a 94 amp 12si, 3 o'clock mounting (amc V8), at napa for just under $100. Ask the counter help for a 84 camaro 5.0 w/AC alternator.

 

[Torxhead]

I would go for the CS series Pete, I understand they work better all around.

 

[hole]

http://www.jeep-cj.com/forums/f7/high-output-alternators-25700/ Half way down in this thread I linked a very informative post by Jeephammer. I'm running a CS144 from the JY for $20 and the pigtail adapter from Napa was another$20. The CS144 is 1/2" bigger in diameter and will require modding your bracket. The smaller CS130 bolts in. The upside to the CS series alts is they charge at lower rpm's (idle ) and no need for any filters for the radio/CB

 

[Torxhead]

Just to share an experience I had with my "Brand new rebuilt" alternator. I did have a alternator bearing freeze up on the road and with a serpentine belt setup it left me stranded. Fortunately, a tow truck came by and he took my last $20 and packed up the CJ to a local parts store. You just can't bring enough spare parts including money. On my current 12si, I wired the "Sense wire" which goes from the #2 terminal to the alternator output terminal. Moving it to the hot line on the gas gauge, this gave me 14.5 volts throughout the CJ. Before I was getting 13 volts to the underdash. I got this idea from reading one of Jeephammer's many posts.

 

[mtnwhlr]

Just to share an experience I had with my "Brand new rebuilt" alternator. I did have a alternator bearing freeze up on the road and with a serpentine belt setup it left me stranded. Fortunately, a tow truck came by and he took my last $20 and packed up the CJ to a local parts store. You just can't bring enough spare parts. On my current 12si, I wired the "Sense wire" which goes from the #2 terminal to the alternator output terminal to the hot line on the gas gauge, this gave me 14.5 volts throughout the CJ. Before I was getting 13 volts to the underdash.

I got a brand new alternator from Rockauto for my daughter Cherokee and it went out in less then one year. So they wanted me to ship it back to them so they could check it out before they would replace it witch could take god knows how long when I need to get her back on the road so I just went to Napa and got a rebuilt one and will never buy something like that from Rockauto again.

 

[Lumpy Grits]

One thing to think about, is the fact that our Jeeps didn't have the best of wiring to start with.
One of the biggest issues I constantly find is poor grounding(GND). I have gone to using ground wires where my fenders and body bolt together.
I also believe the need of a dedicated GND from the dash, to the battery GND.
I also run a winch, air compressor, upgraded lights and off-road lights. Have no issues with my 85amp OEM type alt.
For the winch and starter along with main engine to frame to body GND. I used 4/0 arc-welding wire w/copper connectors.
LG

 

[007]

One thing to think about, is the fact that our Jeeps didn't have the best of wiring to start with.
One of the biggest issues I constantly find is poor grounding(GND). I have gone to using ground wires where my fenders and body bolt together.
I also believe the need of a dedicated GND from the dash, to the battery GND.
I also run a winch, air compressor, upgraded lights and off-road lights. Have no issues with my 85amp OEM type alt.
For the winch and starter along with main engine to frame to body GND. I used 4/0 arc-welding wire w/copper connectors.
LG

Absolutely. Grounds are SO important and SO neglected and SO forgotten about. I had an old 66 Chevy truck once that was giving me fits. Naturally I replaced about everything then almost as a joke, replaced the ground strap from battery to the block and voila - all fixed.

As to Hole's post - Jeephammer / TeamRush knows his stuff on electronics. He's visited my garage on a few occasions and he's good. A good, stockish alt. with good wires and good ground will do all you need. Have a winch - add a battery - leave the alt alone.