How to Replace Alternator 2001-05 Honda Civic

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In this video, we're going to show you alternator replacement. This is a 2003 Honda Civic with a 1.7-liter. This alternator is basically the same for 2001 to 2005 Civic. What you'll need for this repair: new alternator from 1AAuto.com, eight 14mm wrenches with sockets and extensions as well, pliers, flat blade screwdriver, possibly a pry bar and penetrating oil, and a 10mm wrench.

With a 10mm wrench, loosen your negative battery cable first. Pull it up and off to remove it. I'm going to loosen this 12mm nut here which will allow us to loosen up this wing nut and then there's also a bolt right down here that we need to loosen. This 12mm bolt on the front, pull your reservoir up and out of the way. The bolt is right here. Just get your wrench down in, just loosen that one up a little bit. This is your adjusting screw. Hit it with a little penetrating oil down on the threads. Pliers just to get it to go. You can turn it counter-clockwise. The pump should pivot down to loosen up the belt.

Okay, with the belt off, move this 10mm bolt. Remove the 12mm nut the rest of the way and the 12mm bolt and we'll pull the reservoir and pump up out of the way. The ratchet and wrench on this bolt will help. I have the nut off. I'm just trying to pull the bolt off underneath, the whole thing will come up and out of the way.

Right down here, remove this from the bracket. There's just a little tab that you push down right down here. This tab right here. Push it down, that comes off, and then you pull off this rubber boot here to expose the knot that holds the battery wire on. Get them out of there. Then you also want to remove this boot here to expose the harness connection. Press the tab on the side to release it and pull the connection out.

Use a flat blade screwdriver, going to use that to help me press the tab on that connector and unplug the alternator. Use a 10mm socket and ratchet to remove the battery cable, the nut that holds the battery cable on. This is where you want to make sure that you have your battery disconnected or there could be a lot of sparks.

Then down below the alternator there's an adjustment locking bolt right here. Remove that. 14mm bolt here at the top of the alternator, loosen that. Now you have the adjustment bolt here. See this wing nut? You can use a pair of pliers, grab onto it and get it started and free. Then you loosen it up, so you can move the alternator around. We've loosened up the top one, as well as the locking bolt down at the bottom.

The alternator is not showing any signs of moving. This appears to be the original alternator that's been in here for over 10 years, so it could be just the aluminum is kind of seized up this bracket. I'm just going to use a pry bar and try and break the seal a little bit, so that didn't work, so I'm actually just going to take this bolt all the way out. We're just going to shoot the whole top with that bolt goes through with penetrating oil. Let it settle down in.

In order to get this top alternator bolt out, you have to remove this 12mm bolt and this bracket for the power steering reservoir. Pull this bolt out as far as it goes. Get the alternator to move out of here. Okay, so it's pretty obvious that this alternator has probably never been out of this car, so it's just not moving. It's kind of frozen in place. We've already removed the top bolt all the way. We're now going to remove the bottom bolt all the way. Hopefully, you don't have to do this with your vehicle. You should just be able to loosen this one, loosen the bottom one and then turn the wing nut, which allows the alternator to go in and you can take the belt off, but we have to go a little further, because this vehicle is in a little bit rougher shape.

Slide the alternator down the belt can come off and out. The lower bolt out, this bolt pulls as far as you can. Use a good sized pry bar and pry the alternator out. You should be able to bring it up and out.

My adjuster bolt assembly is still frozen up, so I'm going to put a set of locking pliers on here and try and get it to come out and off. I've got my adjuster cleaned up, it spins nice and freely in there. Just use a wire brush clean off the surfaces that are going to rub together there and down here on the bracket, and we'll just apply a little bit of oil so they can slide back and forth nice and easy. Put the bracket down in like that, adjuster bolt through and in. Put it through, have about a centimeter show on the back side there.

Old alternator that we took out of the vehicle, we do just have to change this bracket over to the new one, but you can see the important stuff is it's exactly the same, the connections are the same. New part from one or the other is going to bolt right in and fix up the charging problem if you have one. 8mm socket ratchet extension, remove the bolt that holds this bracket.

Install the bracket onto the new alternator. We're going to lower it down in. Obviously this goes between the bracket up at the top. You want to make sure the bottom goes in behind the bracket at the bottom. Let's get the top in, we're just going to work it around until we can get it to go in. Get that bolt in and started and put it down into place. Going to get this bolt in most of the way but you don't want to tighten it up yet, you still want your alternator to be able to move. I'm going to use a mirror to help myself see. You're looking from the bottom, I'm looking from the top. Going to try and position my adjusting bracket in there correctly. We'll tighten that up but not tight yet until we get the belt on and adjust it.

Feed the belt down in. You can either reach from the bottom, though it's easy enough to get it from the top. Take it off the alternator, on the crank first. Alternator AC looks good. Then you can start tightening up your adjusting bolt.

Okay, just pull your alternator up. Since you've got everything greased well it will move easily and tighten up the wing nut for the adjuster. Tighten up that wing nut until your belt has about 1/4" of play in it. We're going to tighten up the top bolt. We've got our belt adjusted where we want it. Tighten up here. Tighten up, just get it good and tight. Don't over tighten it. Then we'll do the 12mm bolt and replace the power steering reservoir bracket.

Before we put our power steering pump back in place, we're just going to put this bolt right down in here. Bring the pump down. This stud goes right up through here. Push that through. Get this up like that and a large washer nut goes on the back side of that. Put this bracket up in place and a 10mm bolt down in. Push the stud through. You can see it coming out right down there. Put the 12mm bolt back in place. Kind of hard to film. I'll get my big paws in the way. Just one we can tighten up before we put the belt on is this bolt on the top bracket here. Belt just for now, just push it down in. We'll actually get it on the crank pulley below, from below. We'll just put it down on and put it on power steering pulley for now.

You don't have to have your vehicle on a lift or the wheel and tire off. We just did it to make it easier to film, but what you want to do is reach up in here. You see the belt hanging down, just guide it onto your crank and pulley. Okay, now just pull up and you can tighten up your tensioner. Tighten this up. Check your tension. When you push down you should only push down a 1/4 of an inch on the belt. Use a pair of pliers on the wing nut if you need to.

Then basically what you want to do is once you get the tension right, tighten up this upper nut. Run the vehicle for about 5 minutes. Check the tension again. Adjust it if you need to. Make sure you tighten up this nut. Then tighten up the bottom 12mm bolt that holds it. Tighten up the top 12mm nut and tighten up this 12mm bolt. Getting the wrench on there is half the battle. Put your reservoir back in place first. Then your negative cable. Tighten up.

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