# Squeaky Engine



## Highroller814 (Oct 6, 2006)

I have a 97 pathfinder that squeaks like a pig, i believe its comming from the belt drive in the bottom front of the engine since i replaced both the tensioners for the a/c and the alternator and the drive wabbles quite a bit. I just have no clue how to fix the problem. Is there a bearing in the front of the engine that can be replaced to stop the squeak? If anyone else has had this problem please let me know how to fix it.


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## dvdswanson (Nov 6, 2005)

the belts may be glazed from squealing for a long time, you may need to replace them to take care of it. try cleaning the pulleys, dont use an oil-based spray its only a temporary fix. check the idler pulleys to see if their bearings are worn out, and check the tension on the belts. just a little loose the belts will squeal. even a little dust will cause it to.


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## Highroller814 (Oct 6, 2006)

Dave, That was my first solution to the problem, but it only made things worse, my only idea now is that i might have accidentally overtightened the tensioners, and that in turn did some damage to the main bearing. But I know for a fact that its not the belts themselves. 

Any other ideas?


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## 88pathoffroad (Jun 6, 2004)

There is no "main bearing". The crankshaft turns on a series of bearings inside the block.

Try removing one belt at a time and see if the noise stops when you pull one. Spin the accessories by hand to see if they make any noise with the belt off.


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## Highroller814 (Oct 6, 2006)

Thanks 88, I'll try that and see what happens.


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## Burdabit (Jan 9, 2006)

FWIW, I had my belts changed a week ago in preparation for a trip and they have been squealing ever since. It got so bad that I took it to a Nissan dealer at my destination who immediately asked whether they were after market belts. When I said they were, he said that always happens with AM belts but he agreed to look at it to make sure they were installed properly (they were). I'm going to call my mechanic about it next week.


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## littlefish (Jul 1, 2006)

Most After Market belts (AM) should not cause a problem. I have seen belts tightened too tight cause a squeal because they were being jammed into the groove too tightly. Plus it wears the accessory bearing badly. IMHO Gates has a line of heavy duty/industrial belts that is as good a belt as anyone on the planet can sell you. Be it AM or a "Factory" belt made by someone besides Nissan. Face it, Nissan does not make their own belts. This is just an opinion from a old man with over a million road miles.


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## Highroller814 (Oct 6, 2006)

So how tight should the belts be? is there a rule of thumb for how tight/loose they are?


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## dvdswanson (Nov 6, 2005)

I beleive its a 1/4" play up and down on the longest part of the belt. 1/2" total.


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## Tifo (Nov 27, 2006)

OK, hope no one here minds that I dug this back up.

On my 98 Pathfinder, I have replaced the both the idler pulleys (on the A/C and the Alternator) and the accessory belts, and am still having this high-pitched whine/noise. I can't isolate it, and am concerned that it is coming from the timing belt tensioner pulley. I did the timing belt job two years ago when the water pump went out at 60K miles, but didn't see the need (at the time) to replace the tensioner. Could that be what is making the noise? Is that the normal symptom when it starts to go? I really don't want to basically do the timing belt job again to replace the tensioner only to find out that it isn't the source of the noise.................but I hate the thought of catastprophic engine failure as well...if you know what I mean. Anyone have any ideas? I've messed around with the belt tension and the noise hasn't gone away.

Thanks in advance!


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## Highroller814 (Oct 6, 2006)

*high pitched noise*

Tifo, I'm having the same problem, i thought for a little that it might be my ac pulley, but thats a lot of money to sink into it, and apparently since only repair manuals say that you should replace the timing belt tensioner, then most mechanics don't think to do so. If that works out for you, let me know, that squeak is killing me.


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## Zilverado (Sep 25, 2002)

When it comes to tracking down these types of noises, I like using a mechanic's stethoscope, quite cheap at a parts or tools store. Same idea as the medical version, just with a long metal end instead of the circular pad. You just stick the ends in your ears and then place the other (long metal) end on the various components to try and pin point the noise (just don't touch a rotating pulley :loser: ).

I find this has worked for me a number of times when I'm trying to find the source of a noise. Sound travels well through the steel and aluminum parts on the engine and is easily transfered into the stethoscope.

Just a thought...


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## Tifo (Nov 27, 2006)

I've been thinking of doing just that. There is a Harbor Freight around the corner from my office and I might stop in there to see if they have one.


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## Zilverado (Sep 25, 2002)

Good idea. For the amount it costs, it's a great addition to a tool collection.


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## littlefish (Jul 1, 2006)

If it is a belt/pulley surface rubbing that is causing a problem, get a bar of soap and rub it on the belts, one at a time. Then start it up and listen. If the squeaking stops, it is friction between the belt and one of the pulleys on that belt drive. If it does not stop after all the belts have been checked, then it has to be a bearing. The soap will come off in several miles of driving with no damage as the belts warm up.

Make sure to look at the belts/pulleys to verify nothing is out of line. I have seen missing bolts on a power steering pump cock the thing sideways and cause a constant squeal because of the angle the belt drove the pulley.

You did not say if it was a constant squeal/squeak or intermittent.

Best of luck...Littlefish


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## Tifo (Nov 27, 2006)

Hey, thanks for the reply. The soap is another good idea. I haven't done anything on this since my last post, have been traveling for work.

It is a constant squeel. I noticed it seems to be *slightly* higher in pitch right when I get on and off the gas (ie load change), slightly lower in pitch under constant load. The pitch is not different when the motor is hot verses cold.

The belts are definetly tight, at this point possible on the side of being *maybe* slightly overly tight. I have played around with the tension, actually tightened and loosened the belts while the engine was running to look for a pitch change and there really wasn't any.


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## Tifo (Nov 27, 2006)

OK, now that spring is finally here I had a chance to get out in the garage and wrench on the Pathfinder. I bought all new belts from the dealer (all three including the PS belt) and replaced them this weekend. 

I think the PS belt was the culprit for the squeak, and not the two belts that I thought were the problem. When I went to remove it I noticed it seemed a little loose, and the pulleys that it rode on were well-polished in the groove.

But...........................

When I started putting the belts back on, I found something that troubled me and hopefully someone here can help me out. I noticed that the crank pully seemed to have play in it. I could move the part that the two serpentine belts rode on back and fort, almost like it was independant of the center part of the crank pulley while the back part that the PS belt rode on was solid and fixed. The bolt appeared tight and the center part didn't move. I know I had this part off two years ago when I did the water pump and timing belt, and I thought it was all one piece (?). Does this seem right? 

I was in a hurry and put it all back together and the squeal is gone, but the crank pulley issue worries me. I drove the truck about 20 miles this weekend and there were not apparent problems.............

thanks in advance for any help you can give!


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## Highroller814 (Oct 6, 2006)

*Harmonic Balancer*

The front of the crank pully is also called a harmonic balancer, the balancer's job is to eliminate many of the small vibrations caused by the engine/drivetrain. its basically a large steel center shaft that connects to the crankshaft with an outer metal groove for the a/c and alternator belts, the p.s. belt sits on the back of it as well. But between this outer groove is a rubber absobsion gap that does the balancing, and sometimes that rubber spacer will deteriorate or break free, causing that crank shaft to spin independently of the crank pulley, and it squeaked terribly, moving the belts around can temporarily eliminate the noise, but i assure you it will come back. My car had a problem very similar to yours last month, and basically the only thing you can do when you have play in the harmonic balancer/crank pulley is to replace it. its quite a task, but if you're patient and have the right tools it won't take long. you will need to remove the fan blade, the fan sheild, the radiator, and all the belts to remove it. You will also need a harmonic balancer pulley, they have a tool loan program at my local auto zone, it costs $16, plus you get that back when you return it. you will also need 2 fully threaded 3" long m-6 bolts that usually are not included in the kit. The center bolt for the balancer can be difficult to remove occasionally, but if you have something to hold the crank pully while turning it, it is not too difficult. Everything else from here is pretty self explainitory, you may need to take a hammer and tap the center of the harmonic balancer pully as you slowly take it off. Also, if you haven't changed your timing belt, now is an ideal time to do it since you would need to take the harmonic balancer off to change it anyways. Carefully inspect the crankshaft to be sure nothing was damaged during removal or there was no previous damage, also check for any oil leaks from the front seal of the engine. 

Just a small warning, this is a time consuming job, it took me about 4 hours to complete, and if you feel uncomfortable doing it, take it to a GOOD mechanic. 

The balancer itself cost about $270 from the nissan dealer, i saw some on ebay for less, just type in pathfinder harmonic balancer or crankshaft pulley. 

if you take it to a mechanic they will probably charge you around $700 so you can save a lot by doing it yourself

Good Luck


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## Tifo (Nov 27, 2006)

Highroller814 said:


> The front of the crank pully is also called a harmonic balancer, the balancer's job is to eliminate many of the small vibrations caused by the engine/drivetrain. its basically a large steel center shaft that connects to the crankshaft with an outer metal groove for the a/c and alternator belts, the p.s. belt sits on the back of it as well. But between this outer groove is a rubber absobsion gap that does the balancing, and sometimes that rubber spacer will deteriorate or break free, causing that crank shaft to spin independently of the crank pulley, and it squeaked terribly, moving the belts around can temporarily eliminate the noise, but i assure you it will come back. My car had a problem very similar to yours last month, and basically the only thing you can do when you have play in the harmonic balancer/crank pulley is to replace it. its quite a task, but if you're patient and have the right tools it won't take long. you will need to remove the fan blade, the fan sheild, the radiator, and all the belts to remove it. You will also need a harmonic balancer pulley, they have a tool loan program at my local auto zone, it costs $16, plus you get that back when you return it. you will also need 2 fully threaded 3" long m-6 bolts that usually are not included in the kit. The center bolt for the balancer can be difficult to remove occasionally, but if you have something to hold the crank pully while turning it, it is not too difficult. Everything else from here is pretty self explainitory, you may need to take a hammer and tap the center of the harmonic balancer pully as you slowly take it off. Also, if you haven't changed your timing belt, now is an ideal time to do it since you would need to take the harmonic balancer off to change it anyways. Carefully inspect the crankshaft to be sure nothing was damaged during removal or there was no previous damage, also check for any oil leaks from the front seal of the engine.
> 
> Just a small warning, this is a time consuming job, it took me about 4 hours to complete, and if you feel uncomfortable doing it, take it to a GOOD mechanic.
> 
> ...


Hey, thanks for the fast reply. 

I've had the carnkshaft pulley off before when I changed the timing belt 2 years ago. Looks like I will be taking it off again, huh? I've got the crankshaft puller already in my tool set.

Since it is an auto, how do I keep the crank from moving now when I go to spin the bolt out? The last time I wrapped an old belt around the pulley, and then grabbed it with a chain whip while I loosened the crank bolt. Now that the pulley seems to be independant, I can see that probably won't work. Is there a flywheel lock made for these trucks that I can remove the starter and bolt there to hold the flywheel? I have done this on my Porsche and have the flywheel lock for it (for timing belt changes), but I'm certain the lock won't work on the pathfinder. But if there is one out there it would help.

Thanks again!


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## Tifo (Nov 27, 2006)

I found a crank pulley online for $228 plus free ground shipping, so it is on its way. 

I tried to find a flywheel lock online but couldn't find one. Does anyone know of a source for one? 

Thanks a bunch for all of the help so far..........


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## raysz28 (Nov 2, 2007)

Tifo said:


> Hey, thanks for the fast reply.
> 
> I've had the carnkshaft pulley off before when I changed the timing belt 2 years ago. Looks like I will be taking it off again, huh? I've got the crankshaft puller already in my tool set.
> 
> ...


I am having the same problem with my 2000 pathfinder. did you end up replacing the crankshaft pulley? was that the cause of the bad squeaks on starts? 
also how did you get the pulley off with the pulley being in two pieces?
Do you have any tips for me doing this job?

Thanks for your help


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## Highroller814 (Oct 6, 2006)

Yes, the crankshaft pully ended up being around $270 from nissan, they sell them on ebay for less, but the car was in bad shape and it needed to be dealt with asap. go to autozone or advance auto and they will loan you a crankshaft pully remover for $15 and you get that back when you're done with it, you also need some new bolts, that are longer and have more thread on them than the ones that came in my pack, be very very careful not to strip out the existing holes on the pully, or you have to rethread the holes and use a different size bold (my mistake) but once its off, you can breath a huge sigh of relief, it might not be a bad idea to go ahead and replace your timing belt while you're down there, its not that much work, plus you'll probably need to do it sooner or later anyways. 

Good luck!


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## raysz28 (Nov 2, 2007)

I think i will try to replace the timing belt also. do you know of any websites with pathfinder instructions?

thanks


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## 88pathoffroad (Jun 6, 2004)

Here you go.

How to change your timing belt! - Nissan Pathfinder Off-Road Association


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## themuddernaught (Nov 11, 2007)

im actually getting a similar squeal as well. Started about 2 weeks ago with the sound comming and going every once and a while and now is a perminent sound when the truck is on. The sound seems to vary with the acceleration. It's very annoying and will be taking a further look today most likely, let you guys know of any outcomes.


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