big ass alternator?

motaaa · Jan 18, 2010

i have a 90 amp alt on my 87 broncoii but when im running my offroad lights, headlights, and my electric fan, the alt cant keep up and it drains my battery.

i read this but im not really understanding what i can do with the 2.9

i want at least 130 amps, what kind of alt can i hook up to it? i can make new mounts if i need to..

strvger · Jan 18, 2010

www.LMCtruck.com

page 133 in their RBV catalog has them. not cheap, but should do the job. good luck!

AgPete139 · Jan 18, 2010

The Explorer alternators are 130 amps. As to whether they are direct bolt up to a 2.9, I don't think so (not 100% sure). Hopefully someone else can chime in for you.

2.8 & 2.9L are very similar.
Try this: http://www.therangerstation.com/forums/showthread.php?p=596038

http://www.therangerstation.com/forums/showthread.php?p=453296

TRS Alternator Technical Article:
http://www.therangerstation.com/tech_library/alternator.htm

Hope this helps, good luck.

Pete

Original_Ranger84 · Jan 18, 2010

The Explorer 130amp alternator won't work cause it uses serpentine belt pulley. but I am pretty sure i read somewhere an 80's GM 140amp alternator from a 350 will bolt right up to a 2.8L mount which should be the same as a 2.9L

motaaa · Jan 19, 2010

the problem is that the 2.8 engines used alternators with external regulators, and the 2.9 has internal.. so if i used a 80's GM alt i would have to rig up an external regulator somehow

anyone know how to do that?

dennis461 · Jan 19, 2010

Look here, an internal regulator replacement with v-belt pulley...
Call them up..
They stand by their lifetime warranty.
Pos a pic of your alternator.
No trade in required, so yours becomes an emergency spare.

http://www.db-starter-alternator.com/Items/ho-7749-11 200 amp-one wire black powder?sck=2227323&caSKU=ho-7749-11 200 amp-one wire black powder&caTitle=NEW Ford Truck Car 200 Amp High Output Alternator 1965-1992 7749

motaaa · Jan 20, 2010

dennis461 said:
Look here, an internal regulator replacement with v-belt pulley...
Call them up..
They stand by their lifetime warranty.
Pos a pic of your alternator.
No trade in required, so yours becomes an emergency spare.

http://www.db-starter-alternator.com/Items/ho-7749-11 200 amp-one wire black powder?sck=2227323&caSKU=ho-7749-11 200 amp-one wire black powder&caTitle=NEW Ford Truck Car 200 Amp High Output Alternator 1965-1992 7749

damn i wish i had $230..

is it at all possible to take apart my alternator, take the back half of the housing including the regulator, and put it on a high output externally regulated alt?

martin · Jan 20, 2010

the gm alternater is internally regulated.

NMB2 · Jan 20, 2010

ive had the GM 1 wire conversion for almost 5yrs. It was ALMOST a direct bolt onto my 2.8 bracket. I just had to use washers for some spacers on the bottom pivot hole, and all i did was run the wire from the alternator to the starter solenoid.

motaaa · Jan 20, 2010

martin said:
the gm alternater is internally regulated.

would it be a late 80's or what?

NMB2 said:
ive had the GM 1 wire conversion for almost 5yrs. It was ALMOST a direct bolt onto my 2.8 bracket. I just had to use washers for some spacers on the bottom pivot hole, and all i did was run the wire from the alternator to the starter solenoid.

heres the problem: 2.8 engine has external regulator

2.9 has internal

NMB2 · Jan 20, 2010

I understand that. With the 2.8 You still have to keep the voltage regulator hooked up or you lose power to the truck, but with the 2.9 having internal stator and isolator means there is no regulator on the truck to bypass, Its still a bolt in swap. You just swap alternators and run a wire from your alternator to the battery or solenoid. I run the 1wire on my 88 Bronco II as well, I have for the last year and a half. i just left the stock plug hanging incase i ever needed to swap the stock style one back in.

motaaa · Jan 20, 2010

NMB2 said:
I understand that. With the 2.8 You still have to keep the voltage regulator hooked up or you lose power to the truck, but with the 2.9 having internal stator and isolator means there is no regulator on the truck to bypass, Its still a bolt in swap. You just swap alternators and run a wire from your alternator to the battery or solenoid. I run the 1wire on my 88 Bronco II as well, I have for the last year and a half. i just left the stock plug hanging incase i ever needed to swap the stock style one back in.

so i run a wire from the unregulated GM alternator straight to the battery?

NMB2 · Jan 21, 2010

the GM alternator isnt unregulated, its a 1wire internal regulated alternator. You run that SINGLE wire from the alternator to your battery positive or the solenoid.

NMB2 · Jan 21, 2010

ill take a picture of one of mine for you later so you can see.

NMB2 · Jan 21, 2010

here is the alternator

this is what you do with the wire.

vwa-la, you have power.

Hope this helps you!

big ass alternator?

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