trey1010

iTrader: (3)

Hey everyone trying to just change one valve seal. I got the valve cover off and the spark plug on the right cylinder out. So by puttin in a screwdriver i can just feel that the screw driver is touching the top off the cylinder that cylinder is then at tdc? I did the tdc method when doing my cam swap but I could line it up dot to dot then . It is a 99 trans am

Whiteaw57

iTrader: (2)

this works if its a small screwdriver but you dont wan to accidently mistake the hole being small for the top of the piston. my advice is unplug coil packs and take out the plug to the cylinder youre working on. place your finger over the plug hole. have a buddy crank the motor over until air pushes your finger away from the hole and then use a breaker bar on the crank to move the piston up or down and you can use bent coat hanger wire to find the piston. the coat hanger is smaller and much easier to verify youre actually getting piston. if youre confident youre close to the right spot you can just start at the coat hanger portion. good luck!

raven154

iTrader: (14)

Or you could just leave the rockers on and watch the valves. As long as both are closed you know you are on the compression stroke. Then use the tool of your choice to feel the piston.

z99ls1

iTrader: (12)

this would be the perfect reason to use the eoic method. As soon as your exhaust valve on that cylyinder starts to open you can adjust the intake valve. And just before the intake valve on the cylinder closes you can adjust the exhaust valve. So simple and 100% correct

z99ls1

iTrader: (12)

Just noticed you were lookking for a way so ur valve could rest on the piston. I still think you should use the method I said above to get the lifter on the base lobe of the camshaft, but to make sure the pistion is at tdc I would put a metel wire in there and wait for the piston to come up tell you see the wire reach the highest point and than you should be safe to let the valve go down on that cylinder.