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Discussion Starter #1
I have a friend who replaced his timing belt and I think he missed by a tooth. It starts briefly and dies. When he replaced the belt the rear cam sprocket got away from him and he rotated it 360 degrees clockwise to get back to the mark. Does one rotation put it in the right place? We took the covers off and it looks to me like the marks are a bit off on the cams when the crank is at TDC. I guess a good way to ask this is if you took the belt off totally and had to reset the marks, what is the process? Is there only one position on the cams or could they be 180 off? Thanks!
 

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There are marks on each timing gear. If it were off 180° you would be bending valves and throwing codes. Rotate by hand linking up timing mark on crank and check timing marks through plug access on timing covers. Btw, if you can rotate it all the way by hand u are probably close enough to avoid contact between pistons and valves

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Discussion Starter #3
We did line up the timing marks. Tried to start it and it runs briefly, but stalls, acts like the timing is off. The only thing I can think of is the rear cam sprocket, which he rotated clockwise 360 degrees needs to be rotated back 360 degrees. No codes that I can see
 

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Discussion Starter #6
I guess what I am asking here, does rotating one of the camshaft pulleys 360 clockwise put it out of time. Could it be 360 off? I can't see anything else that would be a problem. He did say he spilled anti freeze on the crank sensor when he took the water pump out.
 

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You can't rotate the camshaft 360* without bending a valve as there is a TDC piston up all the time in each bank.
 

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So, the valves of one cylinder are damaged due to the hand rotation of the rear cam? It was difficult to turn the cam, but it was done by hand, not by power tool. Just to sure, is it still possible to rotate the rear cam by hand and cause that damage?
 

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:frown2: so, the valves of one cylinder are damaged from rotating the rear cam 360* by hand, not by a power tool. Just to be sure, is it possible to rotate the rear cam (without the timing belt on) and cause that damage with a ratchet wrench?
 

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Rotating 360°will put it right back where it started . Again I think if it were out 180° you would be hitting and bending valves

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No codes at all? In looking at your pic of the crack, isn't that arrow in the top left where your timing mark should be? I like to remove the plastic cover to see the mark cast in the block for accuracy. Get it dead on then check tops. If not inclined to dismantle to check, compression test cylinders. If significantly out of time, it won't build compression

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