Timing belt walking off gears
#1
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Timing belt walking off gears
So, I just got my engine put together and i've driven it about 15 miles now. When I popped the hood to check everything out, the timing belt was almost off of the pulleys. It has worn a slot in my timing covers. Does anyone have any ideas what might be causing this?
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I will check the tension. Any tips on exactly how to check it? I mean, it feels about right. I did reuse my old tensioner spring (about 80k miles old) but I put a little bit more pressure on it when I torqued the tensioner bolt so that it would be good and tight. It doesn't sing like I have heard overtightened belts do.
#6
Any chance you bent one of he cam gears when removing the belt? Maybe prying a gear off a cam for some crazy reason? Any misalignment of the gears themselves relative to one another or an untrue gear could cause walking.
The belt it self could also be to blame do to some material irregularity causing it to apply pressure on one side more than other or maybe when it was cut there was some type of failure.
I assume there are no obvious signs of irregular wear on the belt giving you any idea of where the pressure causing it to walk is coming from?
If you look straight down at the belt you should be able to see a gear wobble as the belt walks as well.
The belt it self could also be to blame do to some material irregularity causing it to apply pressure on one side more than other or maybe when it was cut there was some type of failure.
I assume there are no obvious signs of irregular wear on the belt giving you any idea of where the pressure causing it to walk is coming from?
If you look straight down at the belt you should be able to see a gear wobble as the belt walks as well.
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Well, this is a head I bought on craigslist, so let's hope they're not bent. The cam gears do not wobble. I'm not sure about the crank pulley but it's an ATI super damper. I will take a look at it in the morning. There is also a fuel leak that I need to fix before running the motor again.
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DO NOT put extra tension on the tension pulley, it says that right in the manual. The spring is all the tension it needs. While you're redoing your timing belt, double check everything it rides on is flat and turns true.
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Well, this is a head I bought on craigslist, so let's hope they're not bent. The cam gears do not wobble. I'm not sure about the crank pulley but it's an ATI super damper. I will take a look at it in the morning. There is also a fuel leak that I need to fix before running the motor again.
#15
In my Integra, my timing belt too would walk. I notice that one of the gears towards the edge was damaged (flat spotted). I replaced that.
Not sure if Miatas have this, but there were 2 plates near the crank that would sandwich and re-align the belt. The belt would go slightly off near the cam gears, but get re-aligned w/ the plates at the crank. I had them installed backwards.
I'd probably check the tension first.
Not sure if Miatas have this, but there were 2 plates near the crank that would sandwich and re-align the belt. The belt would go slightly off near the cam gears, but get re-aligned w/ the plates at the crank. I had them installed backwards.
I'd probably check the tension first.
#17
Sounds like you haven't followed the manual properly. There is a specific set of steps to do to tension the belt properly. I'd suggest following them and see what happens then. Of course there is always the possibility that the belt will continue to track now since it was adjusted that way to start with.
#19
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I pulled the idler and tensioner off and put them back on. I checked the cam gears with a straight edge, they were fine. The crank pulley doesn't wobble. I took some videos and pictures.
#20
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A. Use your camera's flower button.
B. I have no idea what your problem is.
C. Your poor starter and battery.
The 2nd video is really confusing. It walks towards the right immediately, than slowly walks left. Do you have access to a mag base and indicator? I'd check flatness of both pulleys and all 3 sprockets. Not 30 minutes ago I finished installing my own timing belt. After a minor hiccup with one of the cam sprockets being on incorrectly (smoke out the air filter), it started up immediately and didn't budge. I double checked cause I had this thread in the back of my head the whole time.
B. I have no idea what your problem is.
C. Your poor starter and battery.
The 2nd video is really confusing. It walks towards the right immediately, than slowly walks left. Do you have access to a mag base and indicator? I'd check flatness of both pulleys and all 3 sprockets. Not 30 minutes ago I finished installing my own timing belt. After a minor hiccup with one of the cam sprockets being on incorrectly (smoke out the air filter), it started up immediately and didn't budge. I double checked cause I had this thread in the back of my head the whole time.