Quote:
Originally Posted by theiceman
im not sure why you think this .. it is minimized but not zero ... all he is showing is TDC for cylinder one .. has nothing to do with 2 or 3 . or tdc for 4 but 5 and 6 have valves out.
Ive done this job so i can tell you there isnt a spot where everything is tdc on the same bank with no valves open at all ..
the only reason there is no tension on the cover when it is removed its because you have to lock them down first .. it is NOT because where the valves are positioned.
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Sorry but I disagree. On a four stroke engine the valves on each cylinder are closed half of the time, from the bottom of the intake stroke through the compression stroke to the bottom of the power stroke. So the cylinder doesn't have to be at TDC to have the valves closed. In fact on TDC of the exhaust stroke the exhaust valve(s) are closing and the intake valve(s) are opening. So as long as the three cylinders on a bank are between the start of the compression stroke and the end of the power stroke all valves are closed.
I have changed the tensioner pads on 3 engines, which doesn't make me and expert but permitted me to make the error of removing the cover when the engine was not properly aligned (in fact it was aligned for the opposite bank, not the one I was disassembling). When I took the cover off one of the camshafts rose about an inch at the end opposite the chain. When the engine is properly aligned the camshafts rise about a millimeter.
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