I got a Blazer two years ago and I'm trying to learn how to replace anything I can on it. I believe we are having alternator problems and I wanna replace it myself. I don't know if this is something I could mess up or try doing by my self?? I've read about how it's an easy job. I also know you have to remove the serpentine belt and place it back on properly. My Blazer does have the picture of how to put the belt on so that's nice. Can anyone help me out or point me in the right direction?? Also I am willing to get this job done. How much would it roughly cost to have done??
Thanks again for all the help

 

Easy task:
To get the serpentine belt off requires a 15mm (I think) wrench and some leverage on the belt tensioner. Check You Tube for videos....I am sure there is one there about removing a serpentine belt...may not be on a Blazer, but you will get the idea.

As far as other steps....disconnect the negative (black) battery cable from the battery, using a 5/16" wrench.
There are two electrical connections to the alternator to remove; a somewhat large diameter red wire attached with a single nut (10mm I think). Be easy getting this off as sometimes it will turn the bolt which could break the internal wire. May have to use a screwdriver to wedge the bolt against the case and an open end wrench to get the nut loose.
The other connection is a two terminal plug-in that is under the alternator. The small problem here is that you sometimes have to hold the alternator in one hand and use the other to get this connector off...which requires you to squeeze the locking tab, gently rock the connector and pull.....all at the sametime...while holding the alternator with the other hand....and the wiring is short so you are holding the alternator just above where it mounts.

There are two bolts holding the alternator in place, one a torx, other is standard. Once the bolts are out sometimes requires a large screwdriver to pry the alternator out of the pivot....very tight fit.

But that is it. A shop will make money on the markup on the alternator, plus charge an hour labor...will want to sell you a new serpertine belt, new tensioner, battery cables, ...etc.....with the assocated increase in labor charge.

Check out you tube for videos.

Just ask questions here....we will help....that is what we all are here for.

 

Its not that hard like LannyL81 states. However, The most important thing to do 1st IS disconnect the Neg cable from the battery and secure it where it won't hit anything. Then from there its pretty much dealer choice as to what to do second and third and so on. Me I would take the pos cable off from behind the Alt and again secure it so it doesn't it something. Then losen the bolts right below the Alt so you can move it and take the pig tail out of the Alt below the Pos cable. The go for the belt. 1st losen the idler pulley and the belt will give you all the slack you need, now that takes like LannyL81 said a 15mm socket to losen it up and a rachet or breaker bar (1/4" type) put in the slot on the idler pulley and push down and it should almost fall and the belt will become lose. Take the bolts that are securing the Alt on out and remove the Alt...Its pretty much like that. Install is pretty much the reverse except getting the idler pully back into place can be a real son of a gun its spring loaded and you have to bare down pretty hard.

 

Thank you for your quick reply I appreciate the help! The only work I've ever done on the Blazer is replacing the air filter :P If I tried to change the alternator do you think I'd be in over my head? It seems really straight forward and easy BUT I would hate to ruin anything on our Blazer

 

The alternator is quite easy on blazers! Nothing else needs to be removed to get it off and back on, other than the belt. And with a serpentine, you don't even have to adjust the tension, and then hold tension with one hand, while tightening the bolt with the other!

The previous posts have outlined it pretty well. It's about a fifteen minute job. Just leave yourself plenty of time, and make sure you have the right size tools before you start. If you run into a problem, post it up here. A picture of it would help, as well.

good luck!

 

Do it! Working on your Blazer is very satisfying and it brings you closer to the glory that is the S/T-Series truck and SUV from General Motors.

Trust me. I've gained a lot of satisfaction from working on mine.