Used 130 Amp Alternator... less horsepower?

[Paulson]

Hello all,

I have a 2001 5.3l Chevy Suburban and the alternator started going on it (lights would flicker... I'm guessing voltage regulator started going.)

So I went on eBay and purchased a used 130 amp delphi alternator (original was a 105 amp Bosch)... when I received the 130 amp alternator I noticed how tough it was to turn compared to the 105 amp alternator...

When I put in the 130 amp alternator I noticed decreased power and acceleration however there isn't any noise coming from the alternator like the bearing is going out...

Could the problem be from sitting in a salvage yard for so long? Will the bearing get better as it gets more usage? Any way to get some lubrication in the bearing or am I just going to have to deal with it and pick up a new one?

P.S. the 130 amp alternator works great aside from this issue!

Thanks

 

[Trav]

We replaced the 130 amp delphi with a new 150 amp remy unit on the Denali 6.0 turned both turned very easily and smooth.
The higher 130 amp alternator does not work harder by default then the 105 amp only when higher demand is required.
No idea what is making it harder to turn or if it will free up from running.Any bearing noise?

 

[Paulson]

No bearing noise... even at 5K rpm's

I have yet to run a trip on it and see if I get worse gas mileage or not...

 

[Trav]

Run it and see what happens,it sounds like you should be okay.

 

[JHZR2]

You should be OK, the amount of power drawn from the engine is equal to the amount required by the electrical loads. Just because two alternators are rated differently, does not mean that they put out more or less than one another for an equal electrical load.

Both will put out the same current, the bigger one will just put out more if you ask it to...

 

[StevieC]

Most likely a coincidence... Maybe your computer is relearning something since you most likely had the battery disconnected while putting in the alternator.

Drive it for a while and see if a CEL comes on.

 

[berniedd]

You have a problem. A good alternator should not be hard to turn by hand if it's off the car. Something's binding and keeping the new alternator from turning freely. Decreased available power from your engine proves it.

 

[antonmnster]

The resistance has nothing to do with output. If you're turning it by hand, it's not generating anything so the resistance is purely mechanical. That means something is binding and probably causing great heat. This is all happening before we even begin to talk about generating electricity.

Strange that the alts are so small; I'm used to dealing with 120-140 amp units in the german cars.

You've got a defective part.

 

[Torino]

Originally Posted By: JHZR2
You should be OK, the amount of power drawn from the engine is equal to the amount required by the electrical loads. Just because two alternators are rated differently, does not mean that they put out more or less than one another for an equal electrical load.

Both will put out the same current, the bigger one will just put out more if you ask it to...
Yes, that electrical power (amps) is not free. It comes from somewhere--in this case the motor. John--Las Vegas.

 

[Eddie]

+1. any alternator should turn freely when off the car.

 

[Trav]

Since you say its running great with no noise i wont jump on the "you have a problem" bandwagon just yet.
Its not uncommon for junk yard parts to get a little surface rust on the stator and field making them feel a little stiff.The end bearings are sealed so there should be no problem with those.
If you are curious just pop the belt now since it has been running a while and see if it turns freely.If it does then i think your in the clear.

I agree with stevie c the ecm is probably going through a leaning cycle,you have nothing to loose by waiting a bit and see how it goes before condemning the part.I probably wouldn't stray to far from home till i knew its okay.

 

[meep]

higher amp alts are actually more efficient electro-mechanically. they have thicker windings, meaning less resistance, and for a given load, lose less energy to heat.

If you can feel it dragging down that 5.3, it should be about to explode. That little accessory is not capable of dragging down that big engine without self-destructing. My 3.7L jeep has a 160...

M

 

[SteveSRT8]

there are a lot of water damaged parts out there, especially in the used market.

The alt should spin freely with just a twist, with very little friction. Most auto parts stores will test it for free for rated load.

I smell an Ebay 'bargain.

 

[Paulson]

Thanks for everyone's input. I didn't want to spend $300 at oreilly and this was the only 130 amp alt I could find on eBay at the time (only paid $57) so if I do have to pick up a new one I'll simply return this one I bought and eat the postage.

I'll take off the belt and see if it spins more freely now.

 

[CBR.worm]

I just had an alternator rebuilt at a reputable local shop. It was a small alternator for a Nissan truck, when I brought it in it would spin freely, but didn't work. When I got it back it was fairly stiff, but smooth. I called the guy and he said that was normal with the new bearings, brushes, etc. I put it in and it has been working fine so far. I was considering pulling off the belt and seeing if it has freed up any.

 

[mechtech2]

If you felt a difference, it was because the old alt was not working right.
Alternators charge on DEMAND, not a stated output at whatever RPMs.
You have more reserve power available with the beefier alternator, that's all.

 

[The_Jeff]

Originally Posted By: Trav
Since you say its running great with no noise i wont jump on the "you have a problem" bandwagon just yet.
Its not uncommon for junk yard parts to get a little surface rust on the stator and field making them feel a little stiff.The end bearings are sealed so there should be no problem with those.
If you are curious just pop the belt now since it has been running a while and see if it turns freely.If it does then i think your in the clear.


+1

 

[Paulson]

Originally Posted By: mechtech2
If you felt a difference, it was because the old alt was not working right.
Alternators charge on DEMAND, not a stated output at whatever RPMs.
You have more reserve power available with the beefier alternator, that's all.


I'm aware of how an alternator works... I just thought it wasn't spinning freely and can feel it when I drive it that the engine is having to work harder... I'm not putting any greater draw on the alternator than before.

The issue with the old alternator was that the voltage regulator was going... the lights would constantly flicker and when I was pulling my 7x16 enclosed trailer I could definitely tell that it was having a hard time keeping up (A/C was on, both front and back blowers were going full speed, lights were on, stereo was running, subs were going...)

The only difference I've noticed is in regards to how the alternator spins when spinning the belt drive.

I'm going to take off the belt and see if it spins any more freely... I just don't want to be driving down the road, cook the alternator (if it's binding) and have the bearing seize and break a belt (not my idea of a fun side of the road adventure.)

I contacted the person I bought this one from and he said he would ship out another one right away so I'm going to see what the replacement alternator feels like and how it works.

Thanks for everyone's opinions/help!

 

[mechtech2]

Paulson - Why would the guy lay down immediately and ship a new alternator out when it appears this one is OK?

 

[Paulson]

I'm not sure. If the replacement is ok I'll send this one back.

Here's the link to the auction on eBay:
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=270582037131&viewitem=&sspagename=STRK%3AMEWNX%3AIT