Drive belts

Hello, Here is a guide that should help with diagrams below to show you how on your car https://www.2carpros.com/diagrams/nissan/altima/2003

Please let us know if you need anything else to get the problem fixed.

I've changed my belts on my 2001 Nissan altima and the one that goes around the a/c compressor and the first time it melted it off and the second one it screechs and starts smoking, pulley is very hot and belts smoking and I'm not sure why?

What you typed doesn't make sense, but if the belt is smoking, a pulley is locked up. Which one should be pretty easy to identify once the belt is removed.

I've changed the idler pulley because the barings were busted but I was told to tighten it just snug enough you could turn it with no problems with your hand, but I put the belt and it spins but after a while it gets hot and makes a loud noise. Could it be the compressor?

There is no such thing as "tighten it just snug enough". No pulley is adjusted that way. Idler pulleys will have a bearing in the middle that needs to be clamped solidly by the bolt that goes through the center of it. If that bolt is loose, it can allow that pulley to turn or tip slightly. That will cause the belt to slide sideways across it as it goes around it, and that will generate a lot of heat, but it almost always sets up an irritating squeal too.

The AC compressor is typically not a likely suspect because you would have to have two separate problems. The clutch would have to be seized which would simply make the compressor run all the time, and the compressor would have to be locked up.

Ok because my air works and bkiws cool air but the car makes a noise as if the pulley isn't on right.

Try to sight down the pulleys from on top to see if there is one where the edge of the belt peeks out or is not perfectly inline with where it goes around the other pulleys. If you can see where the belt is running off-center, compared to the other pulleys, by as little as 1/16", that is enough to set up a squeal. This can be hard to do because moving your eyes just a little to either side can make the belt appear to be off. This works best when there are three pulleys that you can sight through, such as the crankshaft pulley, the generator or power steering pump on top, and an idler or tensioner pulley in between them.

The squealing almost always occurs where the smooth backside of the belt goes around an idler pulley. Squealing is less likely to occur where the ribbed side goes around a ribbed pulley. Ribbed pulleys are attached to things too that have relatively little tendency to tip or turn.

I get a loud squeal when idling just below 1000 rpms. I think it is the idler pulley but I'm not sure. It sounds like a bearing metal on metal high pitched whistle.

I did read that I would have to loosen the motor mounts and jack up the engine. What is the best way to do this. I don't want to bend or crush anything.

Is this something I can do myself and any step by step instructions, diagrams, pictures would be appreciated.

Thanks

Ok first are you sure that is what it making your noise? I am sure it is a bearing but it could be the alternator bearing or the tensioner bearing and so on. If you have a long screw driver or something like it use it like a stethescope and listen them by toughing it so the braket or what metal is very close to the pulley and on the alternator case and make sure were the noise is coming from. If it is the idler pulley with some help you should be able to replace it. Let me know what you find and we will go from there.

The top one is fine its the bottom one that is squealing but it only does it if the a/c is on.

I've listened and listened and still can't pinpoint the noise. It definitely is a bearing though. I've used a steel rod and placed it against the alternator and the a/c compressor but could not hear the squeal through it. Could it be the water pump? I couldn't get the rod in there safely. Any other ideas? Thanks for your help.

Dandy. That narrows it down a lot. It looks like there's just the idler pulley and the AC compressor. The compressor pulley should spin very easily with one finger. In the front of it you'll see that metal disc with the three bolts in it. You should be able to turn that too but it is going to turn rather hard. The important thing is it will turn with no clunking or locking up. If that happens, the compressor will have to be replaced.

Next, look at that idler pulley. That one is usually adjustable to tighten the belt, and most of the time they are not spring-loaded like the other one. They have to have something loosened to allow it to be moved, then you make the adjustment, then tighten down whatever holds it in place. On some cars that means loosening that nut in the center of the pulley, adjusting it, then retightening that nut. If that nut is loose, it will allow the bearing and pulley to tip and will cause a squeal.

Yes it could be the water pump, using the rod against your ear is the way to listen for it. Did you check all the idler and tensioner pulleys that you could get too?

It is so tight on that side of the engine that I'll do the wrong thing and rip my ear off. LOL.

Well then there is only one other way to check it and that is pull it off and feel and listen to it. Sorry it took so long to get back you we are having a lot of snow here in north idaho we got another 12 inches just today now I have more then 3 feet on the ground so I have been snow blowing and such. Thanks for you patience.

serpentine belt broke four times recently. the only thing different, is car has been having oil all around left side of engine where belt is. could oil be making it come off and or break??

The squeal was the water pump. I came out one morning and there was water under the car. I went for broke and replaced it myself in about 6 hours. It's been almost a week and no leak or squeak from it.

I am now noticing a slight squeak from the alternator now. Could the belt be too tight? I have about 1/4 to 1/2 inch deflection so I don't think it is.

Lastly, I was feeling pretty good about myself and replaced the O ring on the distributor shaft because oil was leaking into the cap. The only tragedy is the little rubber gasket between the cap and distributor broke so I cannot put it in. Nissan does not sell the rubber gasket by itself. They say I have to buy a new rotor to get it. No after market cap comes with this gasket either. Can I use a liquid gasket to replace this? Thanks for all your help.

yes it could but more important, make sure all the pulleys are ok and not broken or chipped. the tensioner is a common failure as it wears and does not let the belt run straight.

Roy