Weird rattling noise

Hello I am new here just got a few questions. I have a 97 GTP that has a weird rattling noise at idle by the water pump. I have narrowed it to three things.
-timing chain/tensioner
-waterpump itself
-harmonic balancer

Now what this rattle sounds like a dying s/c, but with the s/c off the belt, it still makes the noise. Its not crazy loud like a rod or slipped bearing, but its not quiet like a knock, its in between. If I accelerate it by 200rpms past idle the noise stops all together. There is absolutely no change in performance or shakes or mpg loss. From what I see the engine is fine. Just want to have a quick debunking with you guys before i rip apart the engine, and maybe pull it.

Will post vid soon.

Supercharger coupler

its a pulley on the accessory belt then.

take the other belt off and inspect your idler and tentioner and water pump, a/c clutch and alt for noise or loose feeling bearings.

the water pump you want to grab the pulley with 2 hands and push one side in and the other side out, there should be no play.

and with the s/c belt off grab the pulley and turn it one way and snap it back the other way, quickly, if you feel play in the pulley the coupler is bad. you fill feel a click and a thud if bad.

Possible it's the flex plate as well.

Flex is at the other end of the motor Dannyo.

With it cold, pull the accessory belt. Fire it up and dont' let it run for more than a minute. A literal minute. If you still hear the noise it's likely balancer or internal like timing chain dampener. If you don't hear it.. WP or accessory.

Geeze you guys r so much more helpful then my mechanic lol. I should hire you guys instead

Originally Posted by BillBoost37

Flex is at the other end of the motor Dannyo.

I know but it's still possible. I figure that maybe it's making noise and hard to hear exactly where they are coming from.

Hey guys thanks for the info did everything you said and here is the results

-coupler and s/c perfect condition

-the chain and harmonic balncer good

-its the water pump! and I found my alternator is going(it chirps)

Ik its the water pump because I used the "screw driver & ear trick" and the noise is strongest from it. I doubled checked this buy removing the belt ran the engine for about 10-15 seconds didn't hear anything but a little lifter tick(that's normal right? I've read somewhere it was). After that, put everything back on ran it and withing 5 seconds noise came back to life.

Thanks guys

Easy fix. You swapping it yourself then taking it to the mechanic and rubbing it in his face?

first big tip, take the 4 small bolts off the w/p pulley before you take the belt off, next, you need to have a t 55 bit (one of them star tips) to remove the lower idler, and the power steering pump to get the 4 long bolts off.

clean the water pump housing up real good, nice and smooth, no left over gasket. the 4 long bolts need thread sealant put on the threads as they go into the water jacket of the block, coolant will come out when you remove the bolts.

take the fuse box and use some string to move and hold it up out of the way to add a few more inches of room, you looking at the bottom of mine in this pic. if you have the coolant bottle right there remove it too.

use no rtv, put the new gasket in dry.

heres what it looks like off.

thanks for the how too, and unfortunately I don't have time to do the swap myself. This is my DD and need it asap. So to another mechanic then swap then rubbing in the face, or doing a bit of gambling into free labor.

Quick thing though, What else on the water pump would make that rattling the pulley itself had no play in it.

it could be rusted up and sizing. they dont last for ever. if it lasted past 100,000 miles it was on borrowed time anyway.

this job is way to easy to do. it takes no more than a hour first time out. i mean easy. tons of vids on you tube with how to directions the whole way through. this could be done after work for real.

the way i see it, you drop it off its gone for a day or 2, do it yourself and you up and running in less than 2 hours and 45 bucks later you can say look what i did lol

i think my new pump cost like 45 bucks, it came with a new gasket. wait till you see what the shop charges for the 45 dollar part. the part turns to 80, and then the labor. i bet another 175 easy if not more. so call it almost 300 at a shop maybe.

now you know why a lot of us do our own work, or as much as possible on our own. who wants to pay all that extra money when you can spend your time and get it done for the cost of parts, that t 55 bit will cost you like 5 bucks tops too. and the rest can be done with a 25 piece socket set. find them for sale all the time 30 bucks or less. and you get to keep em.

Originally Posted by vtechkiller

Geeze you guys r so much more helpful then my mechanic lol. I should hire you guys instead

We drink beer and eat donuts.

Scott..you know the screwdriver trick for WP pulley bolts, right?
PS.. See the idler stand in Scotts picture. The edge of it is in the way of one bolt. I use a grinder and take a round spot out of it.. socket fits perfectly and WP will never fail again with that easy to get at bolt mod.