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Jumped a tooth?


WyKi
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Hey guys, after installing the T.belt went to start it and it starts rough. Think it jumped 1-2 teeth. I read somewhere that I have to loosen up the cams bolts to install then New belt? I removed the old belt and installed the new one without moving the cams and crank. So I imagine the timing is off. If I take the t-belt off again and move the cams/ timing marks on the cams (punched) to the ones on the cover behind them and then move the crank will that bend any valves? Or will I be ok? How would I find TDC on the crank? Ive done this job on I-4s never on V6s

Sorry and thanks

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You don't want to be spinning the cams/cam sprockets without the rest of the assembly spinning or you risk valve damage. You need to first set engine at top dead center on the compression stroke(make sure the belt is on and tensioned before you rotate anything).

 

An easy way to do this is set the crank pulley marks to the timing mark on the timing cover while watching the dimple marks on the sprockets and lining them up to the protrusion marks on the inside of the timing cover. The far left notch on the crank pulley is 0 degrees if i remember correctly. Might want to double check that one.

 

you should also pull the spark plug for #1 cylinder and make sure that the cylinder is at the top of the stroke (compression stroke). Use something soft like a wooden dowel to stick down the spark plug holed. It should stop just past the threads since the piston is at the top. If it sinks down into the hole, you need to continue to rotate until the #1 piston is at the top of the stroke.

 

There is a chance the crank pulley is not bolted in the correct orientation, so always best to confirm that the sprocket marks are lined up and the #1 cylinder is at the top of its stroke.

 

Once that is all okay, you just remove and replace the belt and tension according to FSM. I personally have always used the "twist the belt 90 degrees, no more, no less" method and it's always worked great for me.

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Most belts have marks on them... Use these marks. When I replaced mine I thought the belt had jumped and as I turned it over a few times the marks were further and further off. As I found out this is by design. The marks on the belt don't hit the same spot with each rotation of the motor.

 

I had to loosen the idler pulley to reinstall my belt.

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