Maximising the performance of the stock alternator (1 Viewer)

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lovetoski

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Like many of you, I've noted that my stock alt doesn't able to keep up with lights/heater/wipers/etc. I've been tempted to just install a higher amp alternator, but after reading lots of posts, reading the book "managing 12 volts" talking to wranglernw, david dearborn, to the guy at madelectric, and a few others, I decided to first make sure that my stock charging "system" was working properly. Turns out it's not a question of the alternator, you've got to make sure the system is up to snuff.

My 60 has a replacement engine, done by the PO, not a real clean install. I've never been sure that the wiring and emissions were done right. To simplify things, I purchased David Dearborns charging system upgrade wiring. Really nice product! I can make cables my self, but his are awesome, and more importantly I got more cables than I expected!

So, first improvement is that I now have all of the right ground wires! Plus, they are so big that any voltage drop is negligable.

Second improvement is that I added a 2 guage wire direct from the alt to the battery positive. I kept the existing wiring intact. (I fused this new wire.) This idea is direct from the guy at madelectric. My system voltage stays a lot more stable with this wire in place.

Third improvement is that I used the slee headlight harness for my higher watt bulbs, but I ran the hot lead direct from the alternator (again a suggestion from the mad guy). This way the bulbs get 14.5 volts and run brighter. The relay harness takes a load off of the rest of the OEM harness, which allows the heater/etc to run better - again further stabilizing system voltage.

Overall impact is very noticable. Used to be that at idle, I had 11.5 volts with lights on. Less with heater/wipers/etc. Maybe got to 12.5 at higher rpm. Now I get 12.5 - 13 volts at idle with lights on, and barely less than that with everything running. I have a solid 14.5 volts at higher rpm.

It's pretty cold in Seattle right now (for Seattle anyway) - but the effect of my new system is that my cruiser starts super fast and easy. No question, this new system is notably better at colder temps.

My alternator was always putting out 14.5 volts (over 1000 rpm) it's just that my poor electrical system didn't allow that juice to get where it needed. Too much resistance.
 
Glad it worked out. What did you fuse the batt direct wire at?
 
On the headlight wiring... you'll burn bulbs out quicker, so don't go spending a lot of cash on high dollar bulbs.

good tips though!

Also, was this in the 80 or 60? I didn't know slee made a 60 series headlight harness.
 
I have been thinking about adding the 2nd charge wire on my 40 and 62, glad to hear someone prolly in the know thinks it a good idea :)
 
David,

Here's the fuse block I used.
http://www.bluesea.com/product.asp?Product_Id=23471&d_Id=7463&l1=7463&l2=
Note that they also have a 35-300 amp version. I used a 60am fuse for now. But if I ever get a higher amp alt, I can just swap in the appropriate fuse. I'm pretty sure that pimp has one of these in his blue 60 - I think I remember seeing it on the PS fender. (Great pics pimp - thanks!)

Doc,

I use Hella H4 100/80 bulbs, approx $8 ea. Lots more light at this voltage, and I made this change over one year ago, with no burned bulbs yet. I keep a few extra's around though. Keep in mind though that our old trucks tend to deliver lower voltage to the lights than newer vehicles. Not sure what the H4's are designed for, but I can see better.

Slee did make a harness for both the 60 and 80. I have one of each. Don't know if he still makes the one for the 60.

One more note I forgot to put in last night...in "managing 12 volts" they talk about the effect of corrosion on different circuts.
For a starting circut, where high amps are needed, corrosion reduces amps considerably. Clean tight connections (with huge freakin wires!) is needed.
For lights, corroded connections still work, amps aren't significantly reduced, but volts go down. Lights still work, but are dimmer.
Based on this info, I pulled all my bulbs, cleaned the contacts as well as I could, used dialectric grease, and reassembled. It's hard to judge the visual impact of this effort, but it makes sense to do I think.
 
I run 80/100 Hella's in all my round headlight cruisers, one set is 2 years old, no burnt bulbs, all have the upgraded harness for more volts.

just did Connies 62, did Hella H-4's with 80/100 and Hella H-1's with 55 bulbs.........CRAP that thing is putting out some light :)
 
you've been a very busy boy....

hey, how about the full title, name of author, and publisher on that electrical book "managing 12 volts" you mention in your post above?

-dogboy- '87 FJ60
 
Dogboy,

Managing 12 volts, second edition
Author - Harold Barre
Publisher - Summer Breeze Publishing, Incline Village NV.
ISBN - 0-9647386-2-7

I think I may have purchased it from wranglernw - located in Portland!
 
lovetoski, you are THE man!! :cheers:

i'll check it out,
thanks,
-db-
 
dogboy2 said:
lovetoski, you are THE man!! :cheers:

i'll check it out,
thanks,
-db-

No - I'm just procrastinating - I need to adjust my valves, but it's cold outside, whereas my computer is right next to a heater vent! Pretty lame really...
 
Pimp,

Glad to hear that you like how Connie's 62 has turned out. I'm helping my sis make a similar upgrade to her 62. I got her off on the right foot for x-mas with some e-code low/high lamps, but stuck with the stock 55/65 watt bulbs because I hadn't found the right harness yet.

You mention in a thread in the FAQ that you got your harness from Wayne Tangen...does he sell them still? Not sure that I want to make one, though the instructions/diagram look pretty straightforward.

Thanks for your help.
 
lovetoski said:
No - I'm just procrastinating - I need to adjust my valves, but it's cold outside, whereas my computer is right next to a heater vent! Pretty lame really...

No, that's what I call intelligent. ;) I was in my freezing cold garage last Monday afternoon trying to do just that, adjust the valves, and long story short, what I got for my efforts: the flu which is still kicking me a week later :whoops:

So although it may appear to be procrastination on the surface, don't confuse it primal wisdom :D

-db-
 
Man, kick ass post. I don't have the drain problem that you were having, but I do see some dragging when everything is on. Sounds like the second charge wire might be the one thing that could improve it overall.

Do you have any photos of what you did? Would love to see that setup.
 
This one goes to the FAQ...

Mike S
 
lovetoski said:
You mention in a thread in the FAQ that you got your harness from Wayne Tangen...does he sell them still? Not sure that I want to make one, though the instructions/diagram look pretty straightforward.

Wayne just made a batch and posted on the 3FE list that he won't be doing another for "a while." There are a a couple circuit diagrams, one with wire lengths, pics, instructions, etc., on the 3FE list Files section if you're up to making one.

Gotta say, Wayne's product quality and attention to detail is top-notch.

-Ken
 
Glad you guys find the post helpful. My camara's at work, and I'm off today, but I'll post some pics tomorrow.
 
I would expect if he does another batch is will be close to a year from now, that how long it was last time. I'd make one but for the $90 it cost from Wayne.......I thought that was a great value.

eshelbyk said:
Wayne just made a batch and posted on the 3FE list that he won't be doing another for "a while." There are a a couple circuit diagrams, one with wire lengths, pics, instructions, etc., on the 3FE list Files section if you're up to making one.

Gotta say, Wayne's product quality and attention to detail is top-notch.

-Ken
 
lovetoski said:
Second improvement is that I added a 2 guage wire direct from the alt to the battery positive. I kept the existing wiring intact. (I fused this new wire.) This idea is direct from the guy at madelectric. My system voltage stays a lot more stable with this wire in place.

QUOTE]

a couple of questions on your added charging wire install
first how did you route it? did you go up to the fire wall and around the engine that way or did you go in front of the radiator? if you went the fire wall route what lengths of cable did you end up using. ie the length from the alt to the fusable link then the section from the fuseable link to the battery?
thanks
Jason
 
Jason,

I didn't have time to post pics today - sorry. The length of wire is about 2 feet. The wire goes from the alt to the battery positive. It does not go to the firewall. The 2 ga wire is pretty thick, and kind of hangs there in space. I have installed a 60 amp fuse in the middle of this wire, so really it's two 1 foot long wires. The fuse will be screwed to the fender. (Right now it's zip-tied to the A/C lines, as it got dark and I ran out of time.)

Not sure that 2 ga wire is really needed. I had it laying around. It might be overkill.

You end up with two wires from the alt to the batter. The OEM wires, including the fusable + the new wire.

Hope this helps. Let me know.
 
Jason has a 62 and as so the alt on the other side of the engine then a 60, so its a longer run.
If it were me on a 62 I would go infront of the rad, between the grill.

lovetoski said:
Jason,

I didn't have time to post pics today - sorry. The length of wire is about 2 feet. The wire goes from the alt to the battery positive. It does not go to the firewall. The 2 ga wire is pretty thick, and kind of hangs there in space. I have installed a 60 amp fuse in the middle of this wire, so really it's two 1 foot long wires. The fuse will be screwed to the fender. (Right now it's zip-tied to the A/C lines, as it got dark and I ran out of time.)

Not sure that 2 ga wire is really needed. I had it laying around. It might be overkill.

You end up with two wires from the alt to the batter. The OEM wires, including the fusable + the new wire.

Hope this helps. Let me know.
 

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