3g alt?!?!
Unregistered User
Posts: n/a
3g alt?!?!
So I bought a 170amp alt. an 8 foot section of 0/1ga wire and an ANL fuse setup ( 200amp ) .
Took 2 hours, installed it all. Cleaned my Pro-M MAF, Intake tube and such.. made it all clean and shiny..
I now watch my volt meter drop down to 12 volts, My headlights and reverse light dim with the gas pedal.. Heaven forbid I turn on my electric fan..
I didn't think something was right with this altenator but decided to give it a try anyway. Took it out for a drive.
The Battery hasnt died, the volt meter stays at 12volts or better but when I take it up to 2000 or higher RPM's, the volt meter pegs to 14volts. At idle.. 12volts.. Headlights dim..
WTFH is wrong with this thing? Internal voltage regulator?
Outside of some pillar meters, neon lights and an electric fan, I dont have **** causing any draw. the 110amp altenator I took out didn't do any of this.
Do all 3g altenators do this?
I'm about to rip this thing out and toss it in Lake Erie and forget I ever even bought it.
I now have to spend tomorrow ripping all this ' mod ' out as I will NOT fire off my solonoids with this thing installed. I do NOT want to have to change engines this weekend due to a misfire.
Took 2 hours, installed it all. Cleaned my Pro-M MAF, Intake tube and such.. made it all clean and shiny..
I now watch my volt meter drop down to 12 volts, My headlights and reverse light dim with the gas pedal.. Heaven forbid I turn on my electric fan..
I didn't think something was right with this altenator but decided to give it a try anyway. Took it out for a drive.
The Battery hasnt died, the volt meter stays at 12volts or better but when I take it up to 2000 or higher RPM's, the volt meter pegs to 14volts. At idle.. 12volts.. Headlights dim..
WTFH is wrong with this thing? Internal voltage regulator?
Outside of some pillar meters, neon lights and an electric fan, I dont have **** causing any draw. the 110amp altenator I took out didn't do any of this.
Do all 3g altenators do this?
I'm about to rip this thing out and toss it in Lake Erie and forget I ever even bought it.
I now have to spend tomorrow ripping all this ' mod ' out as I will NOT fire off my solonoids with this thing installed. I do NOT want to have to change engines this weekend due to a misfire.
Member
Joined: Oct 2004
Posts: 2,232
Likes: 4
From: Coal Region, MTC to be exact...heart of the coal region.
170 amp alt? where did u buy this from?
3Gs come in two flavors, 95A (small case) and 130A (large case). u can upgrade the large case to 200A but the stock 130A actually produces 160ish A at 2,000 rpm and 90A at idle (both mine did when i got them from the junkyard).
so i dont know where or who had this alt before u but it sounds fishy.
was it plug n play or did u need to adapt it to the harness?
3Gs come in two flavors, 95A (small case) and 130A (large case). u can upgrade the large case to 200A but the stock 130A actually produces 160ish A at 2,000 rpm and 90A at idle (both mine did when i got them from the junkyard).
so i dont know where or who had this alt before u but it sounds fishy.
was it plug n play or did u need to adapt it to the harness?
Unregistered User
Posts: n/a
Its a 3g type case. Its being returned. I bought it off a website.. I think I'm just going to buy locally or drive to Summitracing.com in ohio from hence forth. I might ebay small items but..
I took the altenator to a local shop, they ran it and said the internal voltage regulator was amuck. So I bought one locally from them, they had it shipped to their store by close of business the same day.. we tested it on their machine before I brought it home and installed it. Was a grand total of 6$ more.
Between this altenator, a set of ball joints, a rear differential rebuild kit.. I've had nothing but rubbish-luck with anything online. Its a bloody Albatross to me. EVERYTHING I have ordered online, to include a movie DVD has been foul!
I better not order any food-items!
I took the altenator to a local shop, they ran it and said the internal voltage regulator was amuck. So I bought one locally from them, they had it shipped to their store by close of business the same day.. we tested it on their machine before I brought it home and installed it. Was a grand total of 6$ more.
Between this altenator, a set of ball joints, a rear differential rebuild kit.. I've had nothing but rubbish-luck with anything online. Its a bloody Albatross to me. EVERYTHING I have ordered online, to include a movie DVD has been foul!
I better not order any food-items!
Member
Joined: May 2004
Posts: 1,189
Likes: 0
From: Barberton,Ohio
Originally Posted by lifted97ranger
i was thinking the same thing......he may get a serial killer wife...
You can always order from summit. they ship fast and free.. and you can
avoid taxes. If you are going to be in town let me know. We can do lunch
at applebees or something.
ive got a JM alternator and it does the same thing near the same thing that is..
stock i never had a problem i got a 170 ran bigger wires and all..you can hear my compressor die down at stop lights and stuff..system goin a/c on it poos..then idle up..i know it puts out more when drivin but the stock didnt die down this much.
how i fix that?
stock i never had a problem i got a 170 ran bigger wires and all..you can hear my compressor die down at stop lights and stuff..system goin a/c on it poos..then idle up..i know it puts out more when drivin but the stock didnt die down this much.
how i fix that?
Member
Joined: Oct 2004
Posts: 2,232
Likes: 4
From: Coal Region, MTC to be exact...heart of the coal region.
sounds like the wiring isnt compatible ala it isnt letting the exciter wire "kick" on the alt OR its not returning to the altenator somehow.
all the 3G swaps i have seen/done work flawlessly...
all the 3G swaps i have seen/done work flawlessly...
RF Veteran
Joined: Jun 2004
Posts: 10,623
Likes: 6
From: Kennett Square, PA
Small case 3G's have serious undercharging problems at idle when modified for high output.
Large case 3G's tend to produce enough amps at idle to keep things up. I had a 130 amp small 3G and it didn't do crap at idle. My replacement 200 amp large case 3G is an animal -- I love it.
It's a refurb, but I bought it used and paid very little for it. I have a spare regulator for it just in case, and my old 130 amp unit is in the toolbox as a spare. I can change one in about 15 minutes now, lol -- too much practice with changing alternators and pulleys.
I also got rid of my underdrive pulley, and put a smaller pulley on the alternator. This jacks up my idle charge quite a bit -- ideal for winching.
Large case 3G's tend to produce enough amps at idle to keep things up. I had a 130 amp small 3G and it didn't do crap at idle. My replacement 200 amp large case 3G is an animal -- I love it.
It's a refurb, but I bought it used and paid very little for it. I have a spare regulator for it just in case, and my old 130 amp unit is in the toolbox as a spare. I can change one in about 15 minutes now, lol -- too much practice with changing alternators and pulleys.
I also got rid of my underdrive pulley, and put a smaller pulley on the alternator. This jacks up my idle charge quite a bit -- ideal for winching.
Unregistered User
Posts: n/a
Originally Posted by optikal illushun
sounds like the wiring isnt compatible ala it isnt letting the exciter wire "kick" on the alt OR its not returning to the altenator somehow.
all the 3G swaps i have seen/done work flawlessly...
all the 3G swaps i have seen/done work flawlessly...
Wiring was custom made for me by a local place. It was the altenators internal voltage regulator.
From speaking with the folks where I aquired my replacement, a LOT of these ' referbed, higher output ' altenators are DOA or have issues right out of the box. They estimated about a third of all of them they sell are returned within 90 days from purchase. They don't even bother testing them as its a common happening, they just exchange them without question.
I was fortunate enough to know a manager at the local Advanced Auto and she frequents my garage/shop quite often having her Exploder modded. She gave me a ' regional ' discount ( I guess this is better then a store managers? ) .
Its all good. I just need to rip into the wiring I have from my power distribution box under the hood to everything inside the cab. Make a single feed and a bus-bar/distribution type setup in the cab behind the dash.
D is planning on putting in a system. Me needs to have available/reliable current.
D.
D. I found this.The moral of the story is High Amp alts are not very good at low rpms:
Pulley ratio is important to the performance of any alternator. Stock, low-amp alternators tend to have very flat performance curves because they are designed to provide output at slow speeds. High-amp alternators on the other hand tend to have very steep output curves, and as a result have relatively low output at slow speeds but ramp up very quickly. Symptoms of low idle output, such as dimming headlights, usually point to an underdrive problem.
The solution is swapping to either a larger crank pulley or a smaller alternator pulley. On the other end of the scale, Powermaster recommends limiting alternator speed to a maximum of 18,000 rpm. With a pulley ratio in the 3:1 range, you could easily exceed this speed in a drag car that frequently sees 6,000 rpm at the track. Here you would need to run either a smaller crank pulley or larger alternator pulley to reduce the alternator speed.
To calculate your engine’s pulley ratio, divide the diameter of the alternator pulley (A) by the diameter of the crankshaft pulley (B). For example, our Ramjet engine has a 6.750-inch crank pulley, so combined with the 2.625-inch pulley supplied with the alternator, it’s turning at 1,414 rpm at a 550-rpm engine idle. Powermaster rates its alternators idle output at a 2,400-rpm “alternator” idle, so this is considerably underdriven compared to the company’s recommendations, but since the rest of the system checked out OK, it’s fine as is.
Pulley ratio is important to the performance of any alternator. Stock, low-amp alternators tend to have very flat performance curves because they are designed to provide output at slow speeds. High-amp alternators on the other hand tend to have very steep output curves, and as a result have relatively low output at slow speeds but ramp up very quickly. Symptoms of low idle output, such as dimming headlights, usually point to an underdrive problem.
The solution is swapping to either a larger crank pulley or a smaller alternator pulley. On the other end of the scale, Powermaster recommends limiting alternator speed to a maximum of 18,000 rpm. With a pulley ratio in the 3:1 range, you could easily exceed this speed in a drag car that frequently sees 6,000 rpm at the track. Here you would need to run either a smaller crank pulley or larger alternator pulley to reduce the alternator speed.
To calculate your engine’s pulley ratio, divide the diameter of the alternator pulley (A) by the diameter of the crankshaft pulley (B). For example, our Ramjet engine has a 6.750-inch crank pulley, so combined with the 2.625-inch pulley supplied with the alternator, it’s turning at 1,414 rpm at a 550-rpm engine idle. Powermaster rates its alternators idle output at a 2,400-rpm “alternator” idle, so this is considerably underdriven compared to the company’s recommendations, but since the rest of the system checked out OK, it’s fine as is.
Unregistered User
Posts: n/a
Originally Posted by graniteguy
D On the other end of the scale, Powermaster recommends limiting alternator speed to a maximum of 18,000 rpm. With a pulley ratio in the 3:1 range, you could easily exceed this speed in a drag car that frequently sees 6,000 rpm at the track. Here you would need to run either a smaller crank pulley or larger alternator pulley to reduce the alternator speed.
I found a different altenator, it resolved my issues. All is well
Thread
Thread Starter
Forum
Replies
Last Post
hotrod88
General Technical & Electrical
4
Oct 15, 2020 07:40 PM
flyboyjay
Auto Detailing 101
9
Nov 6, 2008 01:53 PM
Rangerboy03lvl2
General Technical & Electrical
17
Apr 5, 2008 08:14 PM
