timing belt moving to outer side of cam gears

[blazin_talon]

i just finished my rebuild. i started the car for a bit then shut it off. when i checked the timing belt, it moved almost halfway put of the outer side of the cam gears. what can be the cause?

 

[rodent]

I've seen this happen with a bad tensioner. Did you buy a new tensioner or re-use the old one? You couldn't tell it was bad but as soon as he replaced it with another tensioner, the problem went away. It could also be your idler pulley.

 

[blazin_talon]

i changed everything except the idler pulley. would a bad idler pulley cause this? i heard a bad idler pulley would move the belt towards the right side (engine side) not the outside.

 

[VTEC_THIS]

Timing belt's too tight if it's walking to the edge of the cam gears. Did you check the hydraulic tensioner, it's supposed to be within spec. You use 2 size drill bits to measure it (not sure of the size off the top of my head, but it's in vfaq).

 

[blazin_talon]

no its not too tight its within spec. what can it be? i know the crank pulley prevents it from moving down at the bottom, but what about the top

 

[steve]

Which direction the belt moves depends on which side is getting more pressure than the other.
The idler pulley or the tensioner arm are both suspects.

 

[rodent]

I agree with Steve. The Idler pulley can cause the belt to walk outside or inside depending which way it angles. If you can't afford a new idler see if you can find a used idler and try that.

 

[blazin_talon]

well its moving to the outside (towards the driver fender) and it comes out like halfway. besides changing timing vomponents, could it be that either the tensioner or idler pulley atr loose?

 

[rodent]

Does it feel loose? A loose belt may cause an issue too. I searched and tried to find similar problem.

http://www.dsmtuners.com/forums/problem-diagnosis/260632-timing-belt-walking-away-head.html

 

[blazin_talon]

thats the weird thing the belt is tightened to specs. like i said every timing component is new except the idler pulley, but it must be something else beacuse the belt comes off just ALMOST halfway!

 

[rbrown86]

I know this is an old post but I was wondering if you ever solved this problem. I am having the same issue and it is driving me insane!

 

[steve]

I know this is an old post but I was wondering if you ever solved this problem. I am having the same issue and it is driving me insane!

The 420A is different than the 4G63 but in my case the timing belt shifted because the post that the tensioner arm pivots on wore out and allowed the arm to shift which caused uneven pressure on the belt. Replacing the front motor mount (which the post is part of) and the tensioner arm fixed the problem.

 

[Boomdeeze]

Is the timing belt suppose to ride the inner side of the cam gears? My belt is flush with the edge of the gears and thats the way it was before I tore it out again to install the new trans. I don't think it ever moves over enough to hang over the gear, but is it suppose to ride the edge like that?

 

[rbrown86]

The 420A is different than the 4G63 but in my case the timing belt shifted because the post that the tensioner arm pivots on wore out and allowed the arm to shift which caused uneven pressure on the belt. Replacing the front motor mount (which the post is part of) and the tensioner arm fixed the problem.

Thanks for the input. Before I bolted up the mount, it was coming off of the front, after I bolted the mount in, the belt moved to the back. I finally figured out my problem though... the PO had apparently done a TB change and for some reason flipped the cam gears over to the 2.4 side... I feel stupid for not looking, but really. Who the hell does that?? Lol. Well, now the car runs but has a pretty terrible miss. Thanks for the replies!

Is the timing belt suppose to rid the inner side of the cam gears? My belt is flush with the edge of the gears and thats the way it was before I tore it out again to install the new trans. I don't think it ever moves over enough to hang over the gear, but is it suppose to ride the edge like that?

From what I understand, that is acceptable. As long as its not hanging over the edge. Someone correct me if I'm wrong though!!

 

[red_talon]

I have tons of trouble with my timing belt until I stopped being cheap. I replace everything new( belt, tensioner, pulley,etc) and no problem anymore.