davidc1

So, the Idler pulley is making a lot of noise and needs to be replaced. Is there any reason that I should replace the whole autotensioner assembly? It appears the pulley can be purchased separately for about $65, the whole auto tensioner assembly is about $110.

Also, can the autotensioner be purchased by itself?

Thanks everyone.

Billman250

Depends on the noise. If it bearing, change just the pulley.

If its the tensioner (binding, knocking noise when you move it) replace it.

davidc1

It appears to be the pulley. Fiirst heard is a few months ago just a little. But, after a day at the track it got pretty loud.

At first I thought it was the diff, then something with the clutch (I've got 148,000mi on it) cause I could feel it a little through the shifter and the clutch pedal.

But opening the hood and looking at it you can see it wobbling and feel it.

But I'm still a little concerned it might be something else. Would it be expected that I could feel it a little throughout the clutch peddle and shifter under load?

The car shifts fine still.

Billman250

You should feel nothing through the clutch pedal, that's bad. If you can you may have thrust bearing damage.

Run the car for 30 seconds with the belt off. See if the noise goes away.

davidc1

Well, I only hear the noise when driving. Aside from the pulley, no other noise when idling or driving.

The louder noise is somewhat transiet, meaning worse sometimes than others. Don't hear it at all when idling (aside from the pulley itself), don't hear it when revving in neutral. Don't hear it much when coasting in or out of gear. Primarily hear it when under load, especially partial load (meaning throttle). Feel it slightly through the clutch pedal when it just starts to disengage. Don't feel it when the pedal is all the way in.

So, running it with the belt off won't tell me anything, because it only makes noise when the car is moving. I thought that perhaps the pulley just made a lot more noise when the engine was under load than when idling. But not correct, huh?

So...is the thrust bearing part of a normal clutch replacement?

Billman250

The load does not change at all on the tensioner pulley while the car is in motion or revving in neutral. reving and driving are the same when it comes to the pulley.

thrust bearing is internal deep in the engine. It keeps the crankshaft from moving in and out. Thre is some play and its normal. i can post the numbers later.

The thrust bearing paly can be checked with a dial indicator on the crank pulley. Just pry it away from the engine, then back into the engine. Be gentle it will move with ease.

Measure the total back and forth movement via the dial indicator.

SgtB

FWIW, the pulleys both take standard bearings. You can press them out and order a new one. The trade size will be stamped on the bearing's race. McMaster Carr should have them for less than $10.

EDIT: The tensioner pulley bearing is a 6203LHX3. Sorry! my notes where a skribble.


You can also get a really good pulley assembly from autozone for $16.99 , and they usually have one on the shelf. I've run one for 35k miles. Here is the link. You will have to install it without the metal shield from the OEM pulley, but it won't hurt anything.

Billman250

I've always wanted to know exactly what those letters mean. I have looked at the sites like BCA and NTN. They have descriptions, but I have not been able to find an exact explanation.

For example, a 203FF is the same bearing. Dimensions are exact, and it will press in and work fine. but the internals are special somehow in the 6203LHX3. High speed? amound if balls? cage material?

SgtB

I can't give you the specifics, but yes that has to due with lubricant type, cage, seal type, flanges, etc. etc.

The LHX3 is specific to NTN part numbers, most are ZZ, SS and things like that. The easiest way is to download a tech spec from NTN's website and it should have a listing of all the suffix meanings.

This should get you started.


FWIW: Any 6203, double sealed, permanent lubed bearing rated over 10k rpm will work.

SgtB

This is Consolidated's suffix listing. Lots of those are industry standard.