pos alternator!

[psduser1]

Ok, I'm in another parking lot, changing out another alternator. Truck started this morning, kinda slow, and yup, 5 miles down the road, I lost my dash lights, gauge lights, etc. I made it to the parking lot at work, and the scangauge showed 10.6 volts!

So, off to Napa, swapped out the alternator, just charging the batteries now.
The question is, has anybody found a decent alternator for 7.3s or any tricks to rebuild them and make them last more than 15 minutes?

 

[ghohouston]

parts store alts are always going to be a toss up. i decided to get a high output alt for my old truck, and never looked back, and no more eating a set of batteries every winter.

 

[mustube]

Batteries and alternators can kill each other, if your batteries weren't charged all the way when you put the old alternator on then you could have killed it. Whenever you put on a new alternator or buy new batteries, always test the other component in the charging system. I have a regular parts store reman unit with no issues, but if this one goes out, I'll be getting a high amp unit.

 

[m j]

I put a pair of Interstate AGM mt7-65 in my truck to the tune of $608, on the way home from buying them V dropped to 11.6V
swung by Lordco for a $150 alternator change in the parking lot, it died in 3 weeks so I got to swap it out in the parking lot too.

remans are great fun

 

[powerlifter405]

parts store alts are always going to be a toss up. i decided to get a high output alt for my old truck, and never looked back, and no more eating a set of batteries every winter.

Yep, this is exactly why I went w/ a DB for my 02-F350. Even from purchased new in 02 up to 07 I went through 3 sets of batteries. I put the HO DB unit in and no problems.

It bothers me that even driving down the road, at night when you roll up your windows how the lights briefly dim, or when you turn on the AC etc.. It tells me that the factory unit cannot support even the factory electrical system.

The factory alt is just barely enough to get by on many vehicles and ford dropped this alt, like they did the power steering pump, from other vehicles into a new platform for which the product failed, IMHO.

ghohouston, I'm tied up this weekend w/ company but if you're around later in the week I need to give you a holla :thumbsup:

 

[ghohouston]

Alrighty, get at me whenever

 

[Ad8 PRODIGY]

Matt at gear head just posted something about a new alternator he is selling. Might be worth looking into

 

[powerlifter405]

Matt at gear head just posted something about a new alternator he is selling. Might be worth looking into

It's a Leece unit so it is probably a good unit but it is only a 6 diode and probably a single bridge rectifier. The research I've done is they specialize in medium duty/class 8 truck alts so I don't doubt they know how to build alternators to go a long distance but only a few of the larger aftermarkets units use more than the 6 diodes and a dual bridge.

For example Singer uses 12 Avalanche Diodes on a dual bridge. On the more expensive DC units they use 12 diodes vs 6. The Singer and DC-XPs cost more but I'm guessing that is the reason why and they don't have the mass capability that Leece does.

Avalanche diodes are optimized for avalanche effect so they exhibit small but significant voltage drop under breakdown conditions, unlike Zener diodes that always maintain a voltage higher than breakdown. This feature provides better surge protection than simple Zener diode and acts more like a gas discharge tube replacement. Avalanche diodes have a small positive temperature coefficient of voltage, where diodes relying on the Zener effect have a negative temperature coefficient.

The more I've read about this system and the dual bridge is basically they perform better and last longer under load and heat. The higher the amp output, the more heat that is generated. From reading the audio forums, one primary issue is heat is killing modded stock type units. I never had a problem w/ my DB but I hear they are basically making junk now but I hear nothing bad about Singer, he warranties his work for life and if a component fails he fixes the item at his cost for the replacement part.

Fwiw the Leece would probably be a good buy for those wanting a good entry level unit VS the more expensive Singer or DC units.

 

[Denver]

DC Power alternators. I have had one in my 02 for 2 years now and no issues. They fix all of the problems with the ford unit and they don't need a core.

 

[psduser1]

These are parts store remans, cause that's what I could get where I was at......

I have a guy close to my house that rebuilds electric motors, guess he and I are going to get friendly, lol. I'm going to have to do some more research on my own regarding the info posted, also, as I know very little about this stuff!
I assume leece is a brand?
Db? Singer? Dc power? Lol, don't know any of these companies, as the stock alternator work great for 170k miles. Of course, I don't have much electrical load other than what came stock on the truck.
As far as battery life, I'm pretty careful about maintaining them. The posts, connections, grounds, etc. get cleaned often. I've heard too many stories about poor connections with this engine not too.
Thanks to you guys for the info!

 

[Gearhead]

Its hard to make diodes running in parallel share the load because there is resistance differences between diodes. The black beast has no diode trio like some alts and the diodes go straight to ground and power. The dual bridge heat sinks are external and there is a fan front and rear.
Leece Neville has been making alternators for a long time. I have one on our 1976 peterbuilt at work. The black beast may be the smallest alternator they have ever made....lol

 

[Gearhead]

So I stand corrected, evidenty they can bin sort diodes and add a small resistance to make them work parrallel. It appears that even this three phase alternator has 12 diodes.