New Alternator Whine... Diodes? Please assist
07-01-2015, 01:56 AM
#1
New Alternator Whine... Diodes? Please assist
Oka I tried to do as much research as I could before posting, even went and got a stethoscope to make sure I could track it down.....
but after 130k miles my alternator started breathing her last breathes. So I hop on Advance website and order a "new" 130A Tough One brand alternator, reason being is I have had a ton of good experience with advance parts and have installed Tough One parts in both my buddy's Jeep and my other buddy's LHS, (alternators and water pumps). So I was comfortable.
Picked it up, got home, installed, and theres a whine. Its not the loudest like a squeal, but a whine thats driving me insane, I can hear it easily in the cab, and this was not there with the old alt. Took it up to the store, swapped another in in the parking lot, still there. So started checking belt and pulleys (no vacuum leaks found either).
Replaced the idler pulley and belt tensioner, nada.
Check power steering pump, nada.
Naked ear I hear it in the front middle of the engine bay. Intake? Nope.
Put a stethoscope on it and the pitch and frequency is identical when im on the alt. as to what i hear with my naked ear
The whine increases volume with headlights on and changes with RPM
So my question after research is, are the diodes of these alternators just poor quality? What might be causing this? Connections are good, pulling 14.4v and my battery is fully charged.... Factory radio, factory headlights, LED lights on back end and interior, belt is Dayco, tensioner is Motorcraft, but Im 99.9% sure its the alternator.
What is a guy to do in this situation? I cant find the OE alternator for the life of me. What alternators have people had success with and has anyone else had this issue? My not-car-savvy friends cant hear it, but myself and my car-savvy friends can.
Would the Big 3 help? New diodes? Im looking to get as clear of a suggestion as possible and help future inter-web users find a solution when they google this.
2002 5.4 2v
but after 130k miles my alternator started breathing her last breathes. So I hop on Advance website and order a "new" 130A Tough One brand alternator, reason being is I have had a ton of good experience with advance parts and have installed Tough One parts in both my buddy's Jeep and my other buddy's LHS, (alternators and water pumps). So I was comfortable.
Picked it up, got home, installed, and theres a whine. Its not the loudest like a squeal, but a whine thats driving me insane, I can hear it easily in the cab, and this was not there with the old alt. Took it up to the store, swapped another in in the parking lot, still there. So started checking belt and pulleys (no vacuum leaks found either).
Replaced the idler pulley and belt tensioner, nada.
Check power steering pump, nada.
Naked ear I hear it in the front middle of the engine bay. Intake? Nope.
Put a stethoscope on it and the pitch and frequency is identical when im on the alt. as to what i hear with my naked ear
The whine increases volume with headlights on and changes with RPM
So my question after research is, are the diodes of these alternators just poor quality? What might be causing this? Connections are good, pulling 14.4v and my battery is fully charged.... Factory radio, factory headlights, LED lights on back end and interior, belt is Dayco, tensioner is Motorcraft, but Im 99.9% sure its the alternator.
What is a guy to do in this situation? I cant find the OE alternator for the life of me. What alternators have people had success with and has anyone else had this issue? My not-car-savvy friends cant hear it, but myself and my car-savvy friends can.
Would the Big 3 help? New diodes? Im looking to get as clear of a suggestion as possible and help future inter-web users find a solution when they google this.
2002 5.4 2v
07-01-2015, 06:03 PM
#2
Senior Member
If I had to guess, the problem is with the rectifiers they used with those builds I expect. - IF it is indeed a whine and not a squeal. You have to be able to distinguish between the two. It's two very different problems.
The best alternators to look for, both expense and longevity considered are the 3G Large case type. I use to have a go to for those, but their site is down and has been for awhile now. A good large case 130 amp will actually put out 160 amps, but you'll need to hunt down a supplier. At least you know what to look for.
With alternators, there are a ton of, -well I guess you could say knock-offs. A lot of 3rd party suppliers are not aware. Know what I mean, your supplier may have good ties with many parts they offer, - just not alts. So you'll have to keep searching I'm afraid, if no one else chimes in with a rock solid supplier.
How good are the large case 3g's? I'm still using my factory original @ 319,000 miles.
Good luck man
The best alternators to look for, both expense and longevity considered are the 3G Large case type. I use to have a go to for those, but their site is down and has been for awhile now. A good large case 130 amp will actually put out 160 amps, but you'll need to hunt down a supplier. At least you know what to look for.
With alternators, there are a ton of, -well I guess you could say knock-offs. A lot of 3rd party suppliers are not aware. Know what I mean, your supplier may have good ties with many parts they offer, - just not alts. So you'll have to keep searching I'm afraid, if no one else chimes in with a rock solid supplier.
How good are the large case 3g's? I'm still using my factory original @ 319,000 miles.
Good luck man
07-01-2015, 06:32 PM
#3
Much Appreciated! It is definitely a whine and not a squeal. Now that you mentioned the 3G and I did some searching I see what youre saying with quality. I found this site,
http://alternatorparts.com/ford-3g.html
if anyone has used it and with what success? Or like you said, if anyone has a good supplier, If I find one I may be getting my money back and popping in a 3G. I see there may be an adapter for the 3G but unfortunately I dont know if I had the 1G or the 3G from the factory.
For now she runs and thats what I needed at the time, better to whine and run than sit and be quiet
I would get the 140A 3G with the single heavy duty rectifier (rated up to 210A)
And I do plan on adding a light bar behind the grill and an upgraded head unit/ speakers, so the extra power in the alternator I will find invaluable
http://alternatorparts.com/ford-3g.html
if anyone has used it and with what success? Or like you said, if anyone has a good supplier, If I find one I may be getting my money back and popping in a 3G. I see there may be an adapter for the 3G but unfortunately I dont know if I had the 1G or the 3G from the factory.
For now she runs and thats what I needed at the time, better to whine and run than sit and be quiet
I would get the 140A 3G with the single heavy duty rectifier (rated up to 210A)
And I do plan on adding a light bar behind the grill and an upgraded head unit/ speakers, so the extra power in the alternator I will find invaluable
Last edited by Bullhorn; 07-01-2015 at 06:42 PM.
07-02-2015, 01:58 PM
#4
Senior Member
Yea that site has been around for awhile. I haven't heard good or bad. Not hearing nothing is usually a good thing. If I were in the market, I might give them a shot.
There's one other Alt supply that builds their own top quality Alts, I can't think of the name darnet...I'll see if I can find them real quick......
Yea, here - http://www.mechman.com/gallery/
These ^^^ are the best you can do IMO. You'll see why once you've seen how they're built. Rock solid but, yea, - pricey as hell!
There's one other Alt supply that builds their own top quality Alts, I can't think of the name darnet...I'll see if I can find them real quick......
Yea, here - http://www.mechman.com/gallery/
These ^^^ are the best you can do IMO. You'll see why once you've seen how they're built. Rock solid but, yea, - pricey as hell!