Is there an easy way to find top dead center?

wigginz

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Installing the Harland Sharp roller rockers and everything in the instructions makes perfect sense except finding top dead center. How do I find it? Is there an easy way? I have a remote start button, but even when I use that, I have no idea when I actually hit top dead center. Any ideas for an amateur mechanic who's not too clear on all the valve train terminology?

I turn the engine using the remote start, but how do I tell when I can't actually see the pistons? Is it easiest to find TDC with the stock rockers before taking them off?
 
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wigginz

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Oh wow, that would be the perfect tool... any idea if a local parts store would have that? Like Auto Zone or something?
 

RAYSIR

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Pull out number 1 cylinder spark plug, then use your start button to 'bump' the engine over until you get compression (air) pushing your finger out of the hole. Then use a small diameter dowl or chopstick to put in the hole to touch the top of the piston. You may need a helper but rotate the engine both ways with a socket and ratchet on the crank bolt till the stick tells you the piston is at the top. The stick will come out of the hole then go back down as you go past TDC. Rotate the crank till the stick is farthest out of the hole. The crank will turn easiest if all the plugs are out so there is no compression. Use the stick on each cylinder if thats what you need to do. On TDC each cylinder the valves are all the way up and springs aren't depressed.
 

Purdue_Boiler_Viper

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Pull out number 1 cylinder spark plug, then use your start button to 'bump' the engine over until you get compression (air) pushing your finger out of the hole. Then use a small diameter dowl or chopstick to put in the hole to touch the top of the piston. You may need a helper but rotate the engine both ways with a socket and ratchet on the crank bolt till the stick tells you the piston is at the top. The stick will come out of the hole then go back down as you go past TDC. Rotate the crank till the stick is farthest out of the hole. The crank will turn easiest if all the plugs are out so there is no compression. Use the stick on each cylinder if thats what you need to do. On TDC each cylinder the valves are all the way up and springs aren't depressed.

That's the way I do it.
 

ViperTony

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Pull out number 1 cylinder spark plug, then use your start button to 'bump' the engine over until you get compression (air) pushing your finger out of the hole. Then use a small diameter dowl or chopstick to put in the hole to touch the top of the piston. You may need a helper but rotate the engine both ways with a socket and ratchet on the crank bolt till the stick tells you the piston is at the top. The stick will come out of the hole then go back down as you go past TDC. Rotate the crank till the stick is farthest out of the hole. The crank will turn easiest if all the plugs are out so there is no compression. Use the stick on each cylinder if thats what you need to do. On TDC each cylinder the valves are all the way up and springs aren't depressed.

This procedure is similiar to how Rob at Tator's Dodge did it during our tech session covering compression and leakdown tests. I tried it and got the hang of it pretty quickly. Jack's chart located here helps too.
 
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wigginz

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Pull out number 1 cylinder spark plug, then use your start button to 'bump' the engine over until you get compression (air) pushing your finger out of the hole. Then use a small diameter dowl or chopstick to put in the hole to touch the top of the piston. You may need a helper but rotate the engine both ways with a socket and ratchet on the crank bolt till the stick tells you the piston is at the top. The stick will come out of the hole then go back down as you go past TDC. Rotate the crank till the stick is farthest out of the hole. The crank will turn easiest if all the plugs are out so there is no compression. Use the stick on each cylinder if thats what you need to do. On TDC each cylinder the valves are all the way up and springs aren't depressed.

Nice, that makes perfect sense. Thanks for the info! Should be able to get this install done soon.
 
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You don't need to pull the plugs or get the piston to *exactly* TDC to put rockers on. Just bump the engine until the intake valve is fully closed on the cylinder you want to work on, then proceed. It will be some time before the exhaust valve opens.
 
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