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Discussion Starter · #1 ·
okay i just changed my timing belt myself. (Newbie) and started my car. The thing is that the car doesn't start except it cranks and there is a loud pop and some smoke. I checked the timing and it should be right i mean i followed the manual. Set it to TDC on the camshaft pulleys and then turn the crankshaft pulley 3 teeth to tighten the belt then tighten the tensioner. Now i have a question does the camshaft pulley need to be TDC when the timing belt is tightened or can it move three teeth with the crankshaft? Thats what i don't understand about the manual. If so my timing is off then eh?
 

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okay i just changed my timing belt myself. (Newbie) and started my car. The thing is that the car doesn't start except it cranks and there is a loud pop and some smoke. I checked the timing and it should be right i mean i followed the manual. Set it to TDC on the camshaft pulleys and then turn the crankshaft pulley 3 teeth to tighten the belt then tighten the tensioner. Now i have a question does the camshaft pulley need to be TDC when the timing belt is tightened or can it move three teeth with the crankshaft? Thats what i don't understand about the manual. If so my timing is off then eh?

it has to be at TDC as well.
if its not, then the pistons are moving up and down and the valves arent opening and closing at the right time.
 

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Memento Mori
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It doesn't have to be at TDC when tightening the tensioner. Bar the motor around until the crank is at TDC and then check the cam pulleys. Whenever you do a timing belt, before putting all the covers back on, bar the motor around and double check the timing and belt tension.
 

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Discussion Starter · #4 ·
so the cam shaft pulleys have to be aligned with each other but not necessarily have to be tdc but the crankshaft has to be at tdc?

Sorry i'm a newb.
 

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Memento Mori
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Everything must be at TDC when you put the belt on, but when you turn it a bit to tension the belt you don't have to bar it around to TDC again to tighten the tensioner.
 

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just put them all at top dead center.
look at this picture.

the crank moves the pistons up and down, the cams open and close the valves.
thats the point of timing. so the valves open when they are suppose to.
now youre not a noob.
 

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ohh another question there wouldnt be any damage from cranking the engine with the timing off would there?
On a DOHC B20a(N)/B21a1, yes. The result is usually bent valves unless you get lucky.

After you get the belt on right, do a compression test. If any of the cylinders have little to no compression, you likely have a bent valve.
 

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You would have to be more than just a couple teeth off to do damage.
 
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