Idler Pulley Wobble

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Mike Z

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Hey Folks,
My son bought a 2005 SE, auto, 4.0 and he and I (mostly me and a wee bit "he") have been doing routine maintenance on it. We live in Ohio and he just got a job offer in Chandler, Arizona so I have been focusing on the cooling system.
I just finished replacing the radiator, the overflow reservoir, the t-stat, water pump, fan clutch, heater hoses and upper and lower radiator hoses. Just for kicks I thought I would replace his idler pulley and tensioner pulley. They looked original (110,000 miles).

As far as the idler pulley (all replacement parts are Mopar), I installed it and torqued it to 35 foot pounds. I'll be darned if it doesn't wobble. Here is the strange thing. If I have the hood propped and am watching it at idle it wobbles, but if I manually increase the throttle body, it smooths right out. Is this normal?

All helpful answers are welcome ;)
 
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Bunch of parts I've bought have been garbage out of the box.

Didn't cross thread the bolt did you?

Might want to pull the bolt and chase the hole with a tap.

-Mac
 
macleanflood said:
Bunch of parts I've bought have been garbage out of the box.

Didn't cross thread the bolt did you?

Might want to pull the bolt and chase the hole with a tap.

-Mac
Click to expand...

Nope. Didn't cross thread. Got irritated so I removed it and put the old one back on. Rolled the pulley across the counter top and it wobbles like crazy. I never would have guessed that I needed to check a brand new Mopar part right out of the box.

I wonder if ordering Mopar parts through Amazon increases the likelihood of bad parts?
 
LONGJP2 said:
So you're saying it had nothing to do with the bolt or bearing.
It was the outside diameter that's off?
Click to expand...

That would be my guess. Bearing seemed to be fine. I switched the bolt and threaded the old one in with the new pulley. Still wobbled.
 
Amazon and eBay are rife with counterfeit products. And a lot of Mopar stuff has been moved to China.

And I've just had shit luck with parts since the pandemic. Nobody wants to make decent stuff or quality check it anymore.

-Mac
 
Mike Z said:
Hey Folks,
My son bought a 2005 SE, auto, 4.0 and he and I (mostly me and a wee bit "he") have been doing routine maintenance on it. We live in Ohio and he just got a job offer in Chandler, Arizona.
I just finished replacing the radiator, the overflow reservoir, the t-stat, water pump, fan clutch, heater hoses and upper and lower radiator hoses. Just for kicks I thought I would replace his idler pulley and tensioner pulley. They looked original (110,000 miles).

As far as the idler pulley (all replacement parts are Mopar), I installed it and torqued it to 35 foot pounds. I'll be darned if it doesn't wobble. Here is the strange thing. If I have the hood propped and am watching it at idle it wobbles, but if I manually increase the throttle body, it smooths right out. Is this normal?

All helpful answers are welcome ;)
Click to expand...

Revving it only fixes it by gyroscopic force and/or whatever the belt does as it spins-

It is bad for the belt- I’d order a new one and send it back.

And always tell them - “don’t sell me poison.”
 
macleanflood said:
Amazon and eBay are rife with counterfeit products. And a lot of Mopar stuff has been moved to China.

And I've just had shit luck with parts since the pandemic. Nobody wants to make decent stuff or quality check it anymore.

-Mac
Click to expand...

I am with you, Mac.

When you buy Mopar parts for your jeep, where are you sourcing them?
 
AndyG said:
Revving it only fixes it by gyroscopic force and/or whatever the belt does as it spins-

It is bad for the belt- I’d order a new one and send it back.

And always tell them - “don’t sell me poison.”
Click to expand...

Makes sense. I knew revving wasn't correcting it, just masking it.

I am sending the pulley back to Amazon and trying Mopar Parts Giant. I have used them before and the parts were fine. I am not a huge Amazon fan for a number of reasons, but sometimes when you want a part quickly, they are hard to beat.
 
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Mike Z said:
I am with you, Mac.

When you buy Mopar parts for your jeep, where are you sourcing them?
Click to expand...

Parts Giant.

I've also taken to ordering three of everything and not necessarily all Mopar.

One usually never ships.

I replaced all my pulleys with Gates...did the same thing as you and replaced them when I bought my Jeep.

My 97 has two pulleys and they are different sizes and parts.

I spent a lot of time cleaning up the pulleys.

Eventually I replaced the crank pulley and water pump...did those while swapping out the timing chain and gear with a Melling.

AC condenser has failed too...so that's going to need replaced.

Tempted to do the alternator at the same time...mine looks sketchy as hell...but I think I'd rather take my chances with one that's working rather than gamble on a remanufactured part. Would love to be able to afford a trail welder...they come with new alternators...

I'm stuck now because I got screwed by a transmission rebuilder. I swapped my AX15 for a rebuilt unit. 6 two hour one way plus trips later over two months and I've cancelled my CC charges. Current transmission has a cracked case and is pouring oil.

Need to save up for an Advanced Adapter or Novak sourced AX15...my cheap rebuilds ancillary costs of gas money, 7 transmission swaps and oil, time, purchasing a new clutch, master/slave and B and M shifter (shop of course said it was my fault their shitty work didn't work.)

Times we live in.

At this point I am no longer preemptively swapping parts. If it's not dead and broken I'm not swapping it...odds are the new part will be a pile of crap

-Mac
 
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macleanflood said:
Parts Giant.

I've also taken to ordering three of everything and not necessarily all Mopar.

One usually never ships.

I replaced all my pulleys with Gates...did the same thing as you and replaced them when I bought my Jeep.

My 97 has two pulleys and they are different sizes and parts.

I spent a lot of time cleaning up the pulleys.

Eventually I replaced the crank pulley and water pump...did those while swapping out the timing chain and gear with a Melling.

AC condenser has failed too...so that's going to need replaced.

Tempted to do the alternator at the same time...mine looks sketchy as hell...but I think I'd rather take my chances with one that's working rather than gamble on a remanufactured part. Would love to be able to afford a trail welder...they come with new alternators...

I'm stuck now because I got screwed by a transmission rebuilder. I swapped my AX15 for a rebuilt unit. 6 two hour one way plus trips later over two months and I've cancelled my CC charges. Current transmission has a cracked case and is pouring oil.

Need to save up for an Advanced Adapter or Novak sourced AX15...my cheap rebuilds ancillary costs of gas money, 7 transmission swaps and oil, time, purchasing a new clutch, master/slave and B and M shifter (shop of course said it was my fault their shitty work didn't work.)

Times we live in.

At this point I am no longer preemptively swapping parts. If it's not dead and broken I'm not swapping it...odds are the new part will be a pile of crap

-Mac
Click to expand...

Oh man, rough jeep times with the transmission. Sorry to hear that.

I laughed out loud (not at your misery) but at your statement that "odds are the new part will be a pile of crap". Unfortunately, true.

I have a 97 also and I just bought an NGK 23151 O2 sensor because they are becoming harder and harder to find. I will keep it on the shelf. Hopefully if/when I need it, it won't be a "pile of crap" :ROFLMAO:

FWIW...I put the old idler pulley back on my kid's 05 and it spins straight and true. Thought I was getting ahead of the game by preemptively replacing it.
 
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Sorry to hear about your troubles with the transmission rebuilder.
Not sure what the transmission rebuilder charged you for the rebuild and what your time is worth, but it certainly sounds like after all that work; you would be approximately at what AA or Novak would charge for their transmission.
 
CharlesHS said:
Sorry to hear about your troubles with the transmission rebuilder.
Not sure what the transmission rebuilder charged you for the rebuild and what your time is worth, but it certainly sounds like after all that work; you would be approximately at what AA or Novak would charge for their transmission.
Click to expand...

$1000 and I thought I was saving myself about that... Advanced Adapter is $1600 and $160 in shipping. Novak is around $1900 and $160 in shipping.

If it worked I would have won.

Now that I've watched their transmission guys pull apart that AX15 I'd do the rebuilt myself. It's not a complicated transmission.

I'd fix the one I have for now if I could just find the back 1/3 of the case.

-Mac
 
macleanflood said:
$1000 and I thought I was saving myself about that... Advanced Adapter is $1600 and $160 in shipping. Novak is around $1900 and $160 in shipping.

If it worked I would have won.

Now that I've watched their transmission guys pull apart that AX15 I'd do the rebuilt myself. It's not a complicated transmission.

I'd fix the one I have for now if I could just find the back 1/3 of the case.

-Mac
Click to expand...

Mac,
Have you tried Beard's Midwest Jeep & Auto for what you need to fix it yourself?
 
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There is a bushing that goes into the bearing. Two styles are available. The OEM OD is larger than the bearing OD and the aftermarket bushing that is smaller than the bearing OD. I just rebuilt my idler using a an NTN bearing. The new bearing seals are red, the bushing is above the pulley. The bearing is $6, it fits the tensioner pulley also.

20221020_130148.jpg
 
Mud Mixer said:
There is a bushing that goes into the bearing. Two styles are available. The OEM OD is larger than the bearing OD and the aftermarket bushing that is smaller than the bearing OD. I just rebuilt my idler using a an NTN bearing. The new bearing seals are red, the bushing is above the pulley. The bearing is $6, it fits the tensioner pulley also.

View attachment 368780
Click to expand...

Hey this is good stuff. The idler I replaced that was out of round was for a 2005, 4.0, but I have a 97 that uses the same pulleys you have pictured here.

Rather than purchasing new Mopar pulleys, especially when quality is suspect, it makes sense to me to press in a new bearing and keep the old one that is fine otherwise.

What was your process for pressing in the new bearing?
 
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