This belt is on my 2.4 in my 05 evo with just over 500 miles. The belt is fraying on the sides on the whole belt(side away from the block) and of course the huge chunk of the belt that's broken off. Has anyone seen what could cause this or could the belt be defective?

 

i think it's fairly evident that it's rubbing on something

 

have a look at the inside of the timing covers. I bet you will find your answer. Make sure the covers are on correctly.

 

How was the gasket for the lower timing belt cover, when you replaced the belt? Very common for them to deteriorate to the point of just flattening or breaking apart over the years, especially when they get oils and other fluids on them. After that, it's pretty easy to over tighten the cover down, which could absolutely cause that sort of wear.

Might want to spin the engine by hand with a big ½ inch ratchet and short extension, and listen for any obvious signs of rubbing.

 

Are you using the belt cover? I would not risk a tiny rock getting getting in there and messing it up.

 

Not the top cover because the oem piece does not fit over the aem gears

 

Honestly, it seemed in good shape just had alot of grease/grime inside the cover. Looks like ill be taking the cover off for inspection.

 

the wear indicates that the belt is slipping off of the cam a bit. the part that is worn, you can see where the belt is further forward of the cam teeth, as opposed to the back cam gear. sorta like it "walked" a little. I would look into why the belt is doing that. I usually see about a 1/16th to an 1/8th" of cam teeth on the gears before the belt. I could be wrong. good luck. I've seen that on fin fans for cooling towers, and the cause usually is gear misalignment.

 

Wouldn’t the gears be the same size if your using a 4g63 timing belt?

 

Get a new belt, and make sure it is aligned properly. The belt is way too far toward the passenger side of the car. You should see cam gear before belt.

 

That belt looks wider than OEM.

 

Agree, you can actually see the imprint of the edge of the cam gears on the belt!

 

Wow never saw that happen.

 

So was this the belt or gears?

 

I've seen this happen (not on 4G63/4, but on other engines) when a bolt that holds the idler pulley (or a bolt holding the tensioner pulley) is bent. This causes pulley to be at a slight angle, and the belt to walk one way or another.

Those bolts bend pretty easily when they are taken off (or put on) an engine with a breaker bar (which puts lateral load on the bolt) As opposed to using a impact gun Or a T-handle wrench, which puts a rotational load only.