Advice on alternator replacement...

Going to attempt to replace a faulty alternator on a '98 Lincoln Navigator.

From what I've read, it's just remove the serpentine belt and unbolt the old alternator and bolt in the new alternator.

Of course, these things always sounds a lot simpler than when it's really done.

For those who have actually replaced an alternator, what kind of snags did you run into if any?

I guess my main concern is the removal and re-installation of the serpentine belt. I'm hoping it won't be too loose upon re-installation.

Any input and helpful links would be appreciated.

 

No need to worry about the serpentine belt being too loose because there is an automatic tensioner pulley to keep the proper tension. One thing you might want to do is change the belt while you have it off, unless it is pretty new already. I would change the belt out too.

BigMan69

 

You have to pull off the air intake assembly up to the throttle body. There is that cover on the TB as well. Use a 1/2' drive ratchet or a breaker bar to move the tensioner pulley. A 3' piece of pipe is a help. Use it a a lever, slide it over the ratchet to give you more leverage. Other than that, it's a pretty simple install.

 

Make sure when you try to loosen the belt tensioner to pull it down and not up. Took me ten minutes to figure that one out.

Other than that, the intake removal will save you lots of headache.

 

Ugh. Okay, got the alternator replaced, but they leave out so many extra things that would be so helpful.

First off, this is a 5.4L engine with AC.

I simply removed the battery completely the night before since it was drained and needed to be recharged.

Next, I couldn't imagine how you would get the alternator out without the coolant hose and the air box hose into the throttle body in the way - so, those had to be removed too.

10mm socket wrench takes care of the plastic cover on the throttle body. The airbox hose to the throttle body looks much easier to remove than the coolant hose to the radiator and thermostat, so that goes. It takes awhile to loosen the hose from the throttle body, but it can be done.

Next is removing the three electrical connections to the alternator. Book just says to remove them. Two of the three connectors are snap-ons with tabs, so be careful when removing those. The third is bolted and you can't tell with the cap on. The cap is colored red on my truck, so hopefully it's the same on others.

Peel back the cap to reveal a bolt. Yup, it uses the same 10mm socket to undo the bolt. Be careful it doesn't fall down into the engine bay.

Now comes removing the belt. The book doesn't say anything about HOW to remove the belt using the belt tensioner. After some looking around, I found out that the belt tensioner needs a 1/2-inch driver and the belt tensioner needs to be pushed away (down) from the belt. Really tough to do on a 4x4 truck that sits high and I'm only 5'8".

I used a 1/2-inch driver and then took out my wheel lug bolt driver. Slipped the 19mm socket over the end of the 1/2-inch driver and the placed the wheel lug bolt driver onto the 19mm socket. Much greater leverage and it made pushing down the belt tensioner VERY EASY.

Once the belt tensioner is in the down position, it's easy enough to slip off the belt.

Alternator is held in place with three bolts. Yup, 10mm socket again. Loosen the bottom two first. It helps if you have a 2" extended, but becareful. I loosened it so much that the socket wrench came into contact with the fan belt and then I couldn't get the socket out. Had to screw the bolt back in to get the socket wrench out, then removed the extended to remove the bolts. The last bolt is on top. A 10" extender helps out to remove this one.

This alternator is heavy when you're leaning over the front of the truck (keep in mind that I've spent the last hour with my back hunched over, so it's not feeling well).

Massage that alternator out through the top.

Getting the new alternator back in is much easier and the install is just reversed of the removal procedure.

Now on to the rear differential speed sensor.......

 

You dont need to remove the coolant hose or airflow hose!!!!! Remove the air filter cover like you are going to replace the air filter, then you have enough slack to push it far enough out of the way. The coolant hose can be pushed over the black support arm enough to get out of the way enough to unbolt the alternator and plugs and coaks it out from the top. Just a little tip to cut down on parts removal and time. I hope my tip helps a bit.

 

Also.... if you stand on a small step ladder or a short stool, it will be much easier to work on your 4X4. I am 6'-2" and I still use a stool that I made just to work on this truck! It just makes it alot easier. I also agree that the coolant hose doesn't need to be removed! I changed my alternator twice in the same day in under an hour. This also included driving time to the parts store twice and fighting with the counter person because they gave me a bad alternator on the first trip! This is an easy repair and it doesn't involve a bunch of tools. Pretty straight foward!

 

If you put each foot on the right and left side of the license plate, in the bumper, it makes a decent standing position from which to work from.