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420A Idler Pulley Adjustment Bolt

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2g420aeclipse

Proven Member
57
2
Jan 3, 2016
houston, Texas
So apparently the adjustment bolt from the idler pulley broke because the bolt was stuck and it wouldn't move. Anyways I've been trying to look for it online to buy one but can't find any. Does anyone know what we sit to get it from or at least know the dimensions?
 
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There are three serpentine belts on these cars... Two with adjusting bolts. Need to be a little bit more specific .
Not bad I keep forgetting about that. Umm is the one that is driven by the power steering, crankshaft and a/c compressor
 
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There really aren't any serpentine belts, there are 3 accessory belts, and 2 timing belts (if the balance shaft belt is to be included), but that's all just being technical.

The crank pulley is the only one that really drives any of the accessory belts, and the steering belt is driven by the water pump belt. The only one of these 3 belts that has an idler is the A/C belt.

If you could post a picture of what you're asking about, I think it'd help more.
 
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There really aren't any serpentine belts, there are 3 accessory belts, and 2 timing belts (if the balance shaft belt is to be included), but that's all just being technical.

The crank pulley is the only one that really drives any of the accessory belts, and the steering belt is driven by the water pump belt. The only one of these 3 belts that has an idler is the A/C belt.

If you could post a picture of what you're asking about, I think it'd help more.
It's a 420a idk if the 4g63 are different
 
I think I have a few extra. Ill post you up the specs on it as soon as I can find them.
 
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Ok here ya go:


M8 x 1.25 x 90mm

(from the bottom of the head to the end of the threads is 90mm, threaded section is 80mm)
 
Its reverse thread.
 
Its reverse thread.
by any chance do you know where to buy the reverse thread bolt cause i checked on mcmaster and they only have it till 40mm long and bolt depot only have the nuts on reverse thread and i don't know where else i can find it.
 
I could really use help! I have a 97 eclipse and my husband broke the bolt that this post is talking and since Mitsubishi discontinued the bolt and I have searched for months for it, my only option is to see if anyone knows where (other than a junk yard) to get one. The junk yard refuses to just sell me the bolt and my husband “bypassed” the bolt but my car is squealing it’s unhealthy for the car I know it is and I REFUSE to sell my car !
 
I could really use help! I have a 97 eclipse and my husband broke the bolt that this post is talking and since Mitsubishi discontinued the bolt and I have searched for months for it, my only option is to see if anyone knows where (other than a junk yard) to get one. The junk yard refuses to just sell me the bolt and my husband “bypassed” the bolt but my car is squealing it’s unhealthy for the car I know it is and I REFUSE to sell my car !
The bolt specs were already posted in this thread by @dustyboner .

M8 x 1.25 x 90mm

Order a full thread if you can. I know it won't work if it is half thread or less.
 
If anybody reading this noticed its reverse thread. If you can't find one mcmaster carr carries reverse threaded rod and you could fab something easily
He could possibly flip the pulley bracket around. Looks symmetrical to me.
 
He could possibly flip the pulley bracket around. Looks symmetrical to me.
I'm confused what that would accomplish.
I honestly don't know why they would do this anyway. I get it. If you "tighten" the bolt you tighten the belt. At least that's the only reason I can see to do this. My son has a hyundai that's like this. I thought it was dumb but I guess it works. I'm not an expert on a 420a.
 
I think the reason these bolts are found bent (or broken) is because someone forgets to loosen the pully bolt before turning the adjustment bolt. I had that problem on my 420A Eagle Talon where the original bolt was missing and someone had installed a regular bolt with two nuts to adjust and it worked very poorly. I found a replacement assembly at the junk yard. To get you through you might be able to carefully apply pressure on the pully with a pry bar and tighten the pully bolt so the pully won't loosen in the slide while running. I did that a few times before I found a replacement. You will have to get the pressure just right to keep the belt from squealing under load. I Hope this helps.
 
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