[digitaldelay]

Thanks chemist, your detailed description and pics allowed me to replace my serpentine tensioner in under 1.5 hours. I would have been done in half the time, but I didn't realize the square hole in the body of the tensioner is for rotating the tensioner with a 3/8" ratchet extension. :doh:

Thanks again!

Jason

 

[mobile]

1998, I have the housing out of the way, belt off, and 2 bolts out. It won't budge. I will try prying. You guys sure the 98 does not have a 3rd bolt??

 

[astroid]

Friday the light came on my '99 Astro and the gauge dropped to 10 amps. I drove a few miles to the Interstate battery shop, they tested the battery (which was just replaced a month ago) and told me to push the emergency brake down one click to shut my headlights off and drive straight home (another four miles). I replaced my alternator on Saturday. Beautiful day in the fifties but as usual with owning a vehicle that has half of its engine under the dash, the procedure was not pleasant.

Others have posted that the job was easy even without removing additional parts???? I removed the air cleaner, the metal tube directly behind the air cleaner, the fan shroud, a small hose that dripped antifreeze that went into maybe the heater core :shrug: . Only then did I have a chance to get the alternator into a position where I could get to the wiring on the rear. As I turned the nut, the nut below the pigtail also turned which snapped the pigtail (which I replaced). I then used a socket on the outer nut and a small needle-nosed vise-grip (a narrow wrench would have worked much better) on the inner nut while holding it down on the concrete driveway with my left foot.The replacement alternator slipped back in with a little nudging. The gauge is now up to 15 1/2 amps.

I had a choice of a brand x replacement for $80, a re-manufactured factory unit for $110(lifetime) and a new factory unit for $130(lifetime). I chose the middle unit. Did I make the right choice? :think:

 

[JayDubya]

I've had bad luck with re-manufactured units twice. Bad bearings shortly after installation. They must pound them in with a hammer. Now I only buy new.

 

[Jasen]

As with all reman. amythig, you never know. I've had them bad at the parts counter, and had them last for years. But I've also put in brand new, only to find out it's bad.

 

[Lumpy]

Friday the light came on my '99 Astro and the gauge dropped to 10 amps...

..The gauge is now up to 15 1/2 amps.

Just a note on terminology. That gauge is reading VOLTS not AMPS.

Glad you got it working. Did you make the right choice? Who can say. If it lasts forever and supplies all the current you need for your particular situation, I'd say you made the right choice.

Lump

 

[Bigblaine301]

If you guys are going o replace your alternator, may I suggest a high output? On EBay there's a guy selling new 125 amp to 220 amp delcos for same price as most new stock from GM. Plus side of doing this is longer lasting and great for accessories, faster battery recovery and electrical system stability. I have a 160 amp on my 2002 and it's amazing. :banana:

 

[CreepiE]

Pulling mine out in this 100+ degree heat... :screaming: This thread has helped tremendously! Needs to be ready by Tuesday for plumbing work!

As mentioned earlier, I am going with the "middle of the road" as far as price.

 

[superjet]

Just wanted to say thanks also for this thread on the alternator. It really helped me save some time with the pics and the great info. I learned some things too!
Ive been a lurker here for a long time and just joined to say thanks and to maybe help some others out if i can.. I have been only driving Astro vans since I bought my first one in 1995. I use them for work as well as play pulling boats, jetskis, M/C's, etc.

 

[Taxi_Rob]

Great thread with great pics and explanations, definitely worth a bump, going to attempt a 96 (parts van) to 97 swap and save a couple hundred in parts and labor...

 

[Taxi_Rob]

Hmmm....no change, battery recovers when parked but drains when running. Bench tested alternator found no problem...must have a short somewhere in the ten miles of wiring under there. Thanks anyway, the job itself was a breeze. And FYI, my 97 had no third bolt, but the engine has been rebuilt twice.

 

[AKwhitetrash907]

awesome thread. did my swap today. took 45 min. would have been less but snapped the wire for the plug and also broke the pigtail for the one with the bolt. was able to ******* rig it back together with a conector/ extension wire for the plug and a new pig tail for the bolt one. this forum has saved me a ton already and ive only had my astro for 3 weeks. thanks a bunch

 

[MuRKRoW]

I've never seen this thread until now and I think I should point a few things out to anyone who is reading the main post!

The folks who tested the battery told me it should be indicating closer to 16/17, but in my case it was reading 14/15.

This is NOT true. Your alternator should NEVER be putting out more than 15.5volts unless you have it isolated from your stock wiring harness! Those voltages will fry all the electrical in your car!

Also maybe your battery just dies when parked overnight. That could be a voltage regulator.

The GM alternators (CS-130 and AD-244) are internally regulated meaning that the voltage regulator is inside the alternator. There are companies like Mechman or DC Power that can make those alternators with an external regulator though. Also, the voltage regulator has nothing to do with the battery draining at night! The voltage regulator doesn't draw power from the battery... it simply adjusts the DC current that the diodes output!

I don't have time to read more of the main post of the thread or the replies so I'm not sure what other information is wrong and if someone has already posted what I pointed out. Anyways, I hope people focus on the removal procedures rather than the other "content" that he posted.

 

[dedsqwirl]

The voltage regulator doesn't draw power from the battery...

A bad voltage regulator can cause the battery to discharge when the vehicle is off. A bad bridge rectifier can also cause the battery to discharge when the vehicle is off.

A bad regulator can also also cause the "battery" warning light to illuminate even though the system is operating normally.

 

[DAMVANMAN]

Friday the light came on my '99 Astro and the gauge dropped to 10 amps. I drove a few miles to the Interstate battery shop, they tested the battery (which was just replaced a month ago) and told me to push the emergency brake down one click to shut my headlights off and drive straight home (another four miles). I replaced my alternator on Saturday. Beautiful day in the fifties but as usual with owning a vehicle that has half of its engine under the dash, the procedure was not pleasant.

Others have posted that the job was easy even without removing additional parts???? I removed the air cleaner, the metal tube directly behind the air cleaner, the fan shroud, a small hose that dripped antifreeze that went into maybe the heater core :shrug: . Only then did I have a chance to get the alternator into a position where I could get to the wiring on the rear. As I turned the nut, the nut below the pigtail also turned which snapped the pigtail (which I replaced). I then used a socket on the outer nut and a small needle-nosed vise-grip (a narrow wrench would have worked much better) on the inner nut while holding it down on the concrete driveway with my left foot.The replacement alternator slipped back in with a little nudging. The gauge is now up to 15 1/2 amps.

I had a choice of a brand x replacement for $80, a re-manufactured factory unit for $110(lifetime) and a new factory unit for $130(lifetime). I chose the middle unit. Did I make the right choice? :think:

I just had the same problem with my 99' as well. How many miles was on yours? I have a little over 80k on mine. BTW you might want to check your brake lines under your van as well. I seem to be having all kind of issues with my van. Mostly unchecked maintenance issues. But i forgot to check the brake lines when i bought the damn thing, so that's to be expected. I love to work on it though.

The alternator replacement is not fun. So i feel your pain. But I did not disconnect any fluid hoses to do it though. The two that are above the alternator moved easily enough where i could manipulate the alternator to get to the wiring in the back once i got it loose. The one thing i did do was forget to put that rubber cover back over the double stud bolt after i had installed the refurbed alternator. I realized how hard it was, so i made a Youtube video in three parts on how to replace the dam thing. It was my first video i ever uploaded and is kinda long winded, but i made so others won't make the mistakes i did. If you want the link let me know. BTW I am doing one on replacing my brake lines, so that's gonna be fun. GL TU

 

[DAMVANMAN]

I've had bad luck with re-manufactured units twice. Bad bearings shortly after installation. They must pound them in with a hammer. Now I only buy new.

I did buy a refurbed, but like you said the bearings can be a problem. I always spin them in the store before i buy them and see how it compares to the new. The refurb one i bought had a little bit tighter spin than the new one, but not bad enough that i did not buy it. Been working like a charm, but If you do go refurb, i would at least compare it to the new one first. It it makes a kind of scraping noise or has a real tight pulley on it do not buy it.

 

[DAMVANMAN]

1998, I have the housing out of the way, belt off, and 2 bolts out. It won't budge. I will try prying. You guys sure the 98 does not have a 3rd bolt??

The alternator has two sleeves in the bolt holes for making it snug. If you have the belt off, and bolts off, just pry gently up on one side underneath of it, and then tap the end of what your using to pry with. It will come out. When you put the new one on, you can use a rubber mallet to tap it in. I used an old wood chisel and tapped it gently down on a thick side of the housing. Still workin. I know this is an old post, but hopefully it will help someone.

 

[SJG]

Great stuff changed my alternator yesterday this post made it simple replaced the idler pulley and tensioner while i was in there got 188,000 miles out of the original alternator
Thanks for the great pictures

 

[simthedude]

Great write up and better than the FSM.
Although the FSM doesn't remove the fan cowl. It was worth removing for the extra room.

 

[bangbus]

Great write-up! Was tons of help when I changed out the stock alt. for a AD244 version.

One tip I'd like to add, watch out for the main vacuum line going across the top of the engine to the passenger side. I broke mine taking the alternator out. That will result in the defrost vents only condition.