High Output Alternators

[laxman21]

Originally Posted by Blazin_Jason

Ya let us know how it works for you. Here are my 2 200 db alts on my 350 swap.

wow!

[Marcinko]

I get the second unit in and installed it. It intially made 14.5 volts and then dropped to 11 volts.

I put my Autozone 105Amp Alternator back on and I get 14 volts and with all pert night electrical on, it drops to 13.8 volts.

Guys am I missing something?

I drove in this morning with my AutoZone 105 Amp alt installed along with a nicely rigged voltmeter so I could read the output digitally. At engine start first thing in the morning it was reading 14.4 volts. As drove into work (about a 40 minute drive) it dropped to 13.8 volts with all pert night electrical on. But the key is, that when I turned all electrical on it would maintain 13.8 Volts...as it should right??

It is hard to believe that two alternators would be bad....but I know it is still possible. Before I request a third unit to be shipped, can anyone tell me of anything I should be looking at to make sure it is not a truck issue as opposed to an HO Alternator issue?

[Marcinko]

Ok guys i have a new issue and I am hoping someone can help me out here.

I took my old alternator that I purchased at Autozone with a lifetime warranty and they tested it and they said it ran fine. I however could hear the bearings goin and ask for a free replacement, which they granted. I installed it along with a new Duralast battery, but kept the old serpintine belt on it.

Here is my issue.

At idle with the truck in park and headlights, A/C, and Stereo running I get about 13.9 - 14 Volts. The second I put my foot on the brake and then put it in reverse my voltage goes way down to 12 5 volts. I put it into drive and then get up above 1500 RPM and it returns to 14 volts. Only when I come to a stop does it drop low.

So I guess it points to a possible voltage regulator, but could it also be one of the following??

1) Possible the battery has some sort of short or defect?

2) the old serpintine belt has grow somewhat loose and and is not grabbing and turning the alternator pully like it should? This could also be the belt tensioner I know, but they put a new one on when I had the engine rebuilt a year ago.

I am totally at a loss other than I know before I got this bone head idea to put a High Output alternator on it ran fine except when I turned on 260 watts worth of KC lights. It then dipped only down to 13.5 volts.


GRRRRRRRRRRRRR



Yes, I will be taking it to Autozone to have it tested...but the machine only test the system running above 1500 RPM, which like I said seems to be ok.

[Blazin_Jason]

You could replace the alt pulley with one of a little smaller diameter. The alt just isn't charging due to the low RPM sounds like.

[Marcinko]

Well after getting frustrated enogh I finally broke down and took it to my local Chevrolet Dealer<<<<gulp!!

After couple of hours I got a call and here is what they found.

1) There is a connector that runs to the blower motor for the A/C. Periodically I would have my AC on high and the blower would stop. No big deal right....wrong. Traced it to this connector and could wiggle it and the AC would blow high again. Well guess what?? You guessed it....short to ground. When I would turn the AC on high it would suck so many amps that the alternator could not keep up. Resoluion they told me...new wiring harness ($1100 + install)....BS!!!!! I told them that I would simply remove the connector and hard wire the damn thing. They told me that they would do that for me, but because it was not the "Chevy way" it would not be warrantied. But they did reassure me that it would be ok and would be safe and durable.. WHATEVER!!!!

2)My main positive battery cable was frayed in a spot that apparently I missed. This was also causing it to "draw down" the alternator.

Moral of the story...and a lesson I have learned the hardway. No matter how good you thing you ahve examined your wiring and connectors, be ABSOLUTELY SURE they are in good shape.

Chevrolet is going to take care of the whole thing, and R&R my new High Output Alternator for $400....for me....worth it at this point.

I'll post back when I get the truck later and let everyone know what my voltage measurements are just we can have some closure on this.

[Marcinko]

The saga continues.

"Good morning calling to let you know your truck is done." My reply, "That's great, now you are sure it is charging and the high output alt is working." To which SHE replied, "yes, we tested it and it runs great!!"

"OK, but did you drive it, set it up to mimic night time driving, with A/C on, Stereo, Brights, while in drive, parked at a red light??"

"Oh yes sir." "Great, I'll be by to pick it up later today" I state and hang up the line.

Later that day-

"Here are your keys." "Thanks" tell the young man who drove my truck up.

I open the hood and inspect the work. Yep, there is the new HO Alt, cable, and connector fixed. Just for my satisfaction I'll hokk the voltmeter up and ut it through it's paces before leaving the lot.

In Park, at idle, 14.5 volts...WOOOHOOO I think to myself.

So i place it in drive, turn on A/C, and lights to simulate being stopped at a red light.

WHAT THE F$*%!!! 12.5 volts!!!!!

So I marely walk in to the office and demand ot see the Service Manager.

I explain to him that the money I just laid down did not fix S%^&!!

He apologized and tried to tell me that most s-10s at idle, in drive with AC and lights on will do that. BULLSH$% I state. First it has a 105amp at idle/200 amp at 1500 RPM high output alternator. Second, this was not happening two weeks ago.

Guys if they tell me that I need a new $1100 + labor wire harness I'll be selling this thing for the spare parts and newly overhauled engine!!

This guys have my truck and tell me that an ASE, factory trained technician looked at it and put it through the ringer to make sure it was good. Then....FFS...it is still F'd up.


Ok, vent over.

I will talk extensively with the Dizz who lied to me tomorrow and make it clear that mighty Chevrolet cannot resolve the issue correctly the first time, as they told me they would...and DID!!!

More to follow...at least I hope people reading this will get some sort of joy...maybe even alittle bit of knowledge from this.

[Calgary ZR2]

That looks great.
For everyone's information, I contacted MSD and found out they do not make a mounting bracket for the Blazers/Jimmeys yet. They think later this year or 2008 thay may have a system set up.

Very nice set up you have.

Vern

[Marcinko]

Ok, Chevrolet called this morning.

Here is the scoop.


At idle my alternator is not turning fast enough to generate more than 12.8 volts. As soon as you get about 100-150 rpm above idle it kicks to 14.5 volts.

They reccommend that I get something called an "idle kicker" which is an aftermarket product they tell me that will bump my idle up enough to keep me out of the red zone.

Has anyone heard of these? If so, any idea on where to get one and how hard they are to install.

As a side note, I have the smaller of the two pulley's they sent with the HO Alt installed. Unless there is an even smaller pulley out there, i think that may be a dead end.

Any help would be greatly appreciated.

[Marcinko]

Anyone??

I tried to bump the idle with the screw on the TB, but as it should, the ECM brought it back to 600-650RPM.

Essentially if I drive at night with my headlights on, AC running on high (Arizona Heat ya know), and my stereo, I dip low enough that the amp on the stereo kicks off, lights dim, etc.

If there is a way to get this to idle at about 700 RPM (which I tested while holding the brake to simulate being at a stop light) everything stayed within limits.

BTW - The pulley on the HO Alt is 2", which is less than the stock pulley. I have ordered a 1 7/8 " pulley to see if this will help me out. Just have to be careful not to over rev the engine.

Guys this is really frustrating. Does anyone have this "dipping" of voltage??

[Blazin_Jason]

Wish I knew. Somehow need the ECM to up the rpm. Can stock computers be reprogrammed?

[Marcinko]

Well I have a new HO Alt delivered and am expecting a 1 7/8" pulley this afternoon. I'll be doing a basic R&R of the Alternator and installing the smaller pulley. I am also going to look at the ground cable to make sure it is making good contact and is in good shape. I may ad one additional ground cable for widen the path of least resistance.

I am hoping dropping from a 2" to a 1 7/8" pulley will give me that extra RPM on the alternator that I get when I sit at about 700 RPM on the tach.

We shall see!!

[Calgary ZR2]

I worked for Sony of Canada for 10 years and had clients with the same problem.

After intalling a smaller pulley we would replace the battery cables with thicker cables and use more than one negitave cable. The most important thing would be intalling a power capacitor, somtimes even two or three. Most guys would combine this with a deepcycle battery. The best power capacitor we found for quality, lifespan and service are the ones made by Monster Cable.
Here is a link of the one we used all the time.
Best of luck.
http://www.monstercable.com/mpc/prod...C.asp?pin=2837