What can fry an alternator?

harleys dad

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We run nothing but 55 AMP, the higher amps seam to fail quick as many of my friends have found out. Vw is to simple to wire to be at fault but anything can happen. Depends what make Alt you are using? I didnt read all the post so if all this has been said I didnt read it.
 

Jacob Wisdom

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Just remember to tell us what you found
These type things intreage me just by finding out absolutly without a doubt what the problem REALLY is
Knowledge is power



Although painfully sometimes
Absolutely
Time for an exorcism.
Any recommendations?
Bring it to my shop in Pasadena.... I would like to have a shot at it....
Will definitely add you to our list of options, what's the name of your shop? One of our team members is confident he has an electrical engineer in mind that will solve this for us so we're going to give him a go
like i said, its most likely gonna be a simple item, like, the ground wire install, was it checked?, are all connections soldered or just crimped?, i like the stand alone t/s method, eliminating the current wiring job& adding a Very rudimentary charging system to run Just the engine , then test to see if it fails, then if so call the priest..
You may be right, though all connections are new and have been done by very experienced hands. They're all just crimped to the best of my knowledge
What specifically is failing? They just stop charging? Catch fire? Armature fall out? Let's the magic smoke out?
The voltage regulator and diodes seem to be failing, the sequence is not clear
Sent u a pm with my number. I can use that $1000 bucks!
Responded!
Ok, went back and reread some of it, you said they looked like they were getting hot. What belt setup? Picks of it? Propper tension?
I don't have photos, but everything is what was recommended to us by Adam Wik so it is proven. Tension is correct
What’s up guys. I have chased the same problem before. I’ve had the 4+ alternator race.
1 of the big things I did learn that if u roast the 1st alternator then u drive 20 minutes not charging then u pull into your pit, install the new alternator, get it started and take off!
This is where the next problem started.
Your car has say 40 Amps running stuff. U got a 75 amp alternator. That should be ok but now you asking your alternator to charge a 680 battery too. That’s where the chain effect of failure comes in.
If u roast an alternator u need to rapidly charge your batteries in ur pit for a good 20-30 minutes.
This really helped me out. The alternator is not a battery charger. It’s there to run accessories and sustain the voltage. Make sure batteries are fully charged!
Hope this helps. Good luck and be safe!
This is an interesting possibility that we have not fully explored, I appreciate you offering it
are you running a 911 fan shroud and fan if so and you are using the fan ring for a ground move it to a different spot.
It's a type 1 shroud
We run nothing but 55 AMP, the higher amps seam to fail quick as many of my friends have found out. Vw is to simple to wire to be at fault but anything can happen. Depends what make Alt you are using? I didnt read all the post so if all this has been said I didnt read it.
Yeah we've considered this, the problem is our car requires up to 65 amps of power draw when everything is activated during a night race. We have tried many different alternators, the best we could get our hands on
 

harleys dad

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Absolutely

Any recommendations?

Will definitely add you to our list of options, what's the name of your shop? One of our team members is confident he has an electrical engineer in mind that will solve this for us so we're going to give him a go

You may be right, though all connections are new and have been done by very experienced hands. They're all just crimped to the best of my knowledge

The voltage regulator and diodes seem to be failing, the sequence is not clear

Responded!

I don't have photos, but everything is what was recommended to us by Adam Wik so it is proven. Tension is correct

This is an interesting possibility that we have not fully explored, I appreciate you offering it

It's a type 1 shroud

Yeah we've considered this, the problem is our car requires up to 65 amps of power draw when everything is activated during a night race. We have tried many different alternators, the best we could get our hands on
i in all my years racing vw powerdcars have never stayed within the 55 amp the alt produces have alwaysrun lawn and tractor battewrys and have never lost a alternator. thats running a lot of kc daylighters in the day. like i said the higher output alts are trouble sorry to say
 

5racer

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i in all my years racing vw powerdcars have never stayed within the 55 amp the alt produces have alwaysrun lawn and tractor battewrys and have never lost a alternator. thats running a lot of kc daylighters in the day. like i said the higher output alts are trouble sorry to say
went though the same problem with customers buying the over rated after market L S ,s alternators after lots of money and long days they went to the stock gm,s
 

Bricoop

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Very curious as well. A few weeks ago we spent half the night before a race trying to figure out why our brand new out of the box GM 1 wire wouldn't fire. Turned out to be a non-self-exciting alternator. Had to be "excited" every time the truck was started. Made a harness, wired it to a small switch in the cab.
 

johndjmix

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Didn’t see it listed but I once had a similar issue on a thing I built….that used an alternator. It was an old lawnmower I had converted into a generator (middle school project!).

Turns out I was spinning it so fast (bad Pulley size combination) I was breaking bits of the stator off inside, destroying it.

Once I slowed it down a few thousand rpm it never failed again.

That’s the only time I had any issue with constant alt failures.

—john
 
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