I was running my 4runner and noticed the timing belt on the drivers side cam gear looked visually like it was hopping on the gear while the engine was running.

What is the cam gear made out of? If it's a forged metal then I would not need to not worry about it being bent because it would have just broke when I tried to take it off.

 

I would think it would be pretty hard to bend that piece. Are you sure you got the little knock pin seated in the knockout properly?

Jason

 

im not sure what exactly there made out of but my stock cam gears on my supra years back when i bought it had the same thing, i thought it just wasnt seated right but i took it off and inspected and it was bent pretty bad, i dont even know how something like that would even happen, i'll see if i can dig up the pic for you, car ran fine though

 

Are you talking about the little metal pin that aligns the cam gear with the cam shaft to TDC? I never took it out. I didn't even use the method the FSM said to get the timing belt on. All I did was loosen the tentioner and pulled the drivers side cam gear off to synch the timing belt, seemed easier to do it this way. I never noticed if the pin was bent, didn't inspect it. I don't see how it could be. Even if the little pin was bent I don't think it would cause what I'm seeing. The cam bolt is all the way in at FSM torque lbs spec. (80 or 81 I think).


If it really does cause this, anyone have a spare?

 

So your cam gear WAS bent?

 

Yes that is the knock pin. I didn't use the FSM method either but I was asking if your knock pin is holding out one side of the cam gear. The pin slides into the cut out in the cam gear and I thought if it wasn't in there properly that it would cause the gear to sit funny once it was torqued down. Simple things first right?

Just trying to clarify myself here. My apologies if you understood the first time.

Jason

 

That pin is shaped like a curve on one side and flat on the other right? I think I had to fool with the passenger side briefly if I remember correctly. There is no way you could install that wrong if it was bent at all, you wouldn't beable to insert it!

 

yep the cam was very bent

 

If you say the belt appears to be hopping , have you taken a good look at the tensioner ?

 

My tensioner is tight and is new. The 90 version is spring loaded. The timing belt doesn't slip.

 

Well then it sounds like it is out of round then if it appears to be hopping unless the belt may be thicker in that spot and your seeing a hump in it like that , speaking of out of round - ever drop that cam pulley ?