Bump the engine over as you watch the valves work on #1 cylinder. As the intake valve just closes, now watch for the timing mark to come up to the timing tab. When you set it to the zero mark, you should theoretically be at TDC for #1. To double check to see if you got it right, roll it over more, and then the exhaust valve will start to open next, not the intake.

(When building the engine you normally check to see if that mark is accurate when the heads are off, using a dial indicator.)


Then align the rotor for the #1 wire on the dist cap, and recheck the rest of the plug wires for correct firing order.

 

The way I do it is to disconnect the coil and remove the number 1 spark plug, stick your finger in the spark plug hole and rotate the engine. When the compression pops your finger out of the hole you are pretty darn close to top dead center on the compression stroke. This should be close enough to TDC to get the distributer aligned close enough to start the motor.

To get a closer reading of the true top dead center, then stick a piece of wire into the spark plug hole and touch it to the piston top. Rotate the engine by hand back and forth and watch the movement of the wire. From this you should be able to tell when the piston is at the top of its stroke. This is close enough for setting your timing mark. Thousandths of an inch aren't important here.

 

i usualy remove the plugs and drop a wooden dowel (or somthin gof the sort) into the #1 cylinder and turn it over by hand until it is at its furthest point out. Havent had any issues yet

 

the best way is with a dial indicator and a degree wheel with the head off....but im guessing the engine is together so i would just disconnect the coil pull number one plug out and crank the motor over till you feel the compression come out of the hole... the timing mark on your balancer should be on zero :thumbup:

 

Auto parts places and some of the online stores (e.g., Summit) sell a TDC tool that screws into the #1 spark plug hole. I think its basically a spark plug with the center electrode replaced by a metal rod that touches the piston. The rod moves up and down with the piston and you just look for the highest point in the travel.

Bruce

 

I agree with 75gmck25. It the tool I used on mine and turning it over by hand
I know the motor was dead on at TDC which made me get the new balancer on the crankshaft at exactly the right point to get it perfectJust make sure if you use this tool, do not use the starter at all or you will damage your motor

 

Which size?

Saw several on sale at Summit Racing (14mm, 12mm, and 18mm thread)

Which size should I get for a 1984 351W or am i reading the description wrong?

 

i took an old spark plug and busted out the ceramic, you can spin the motor over with the starter and it will "whoooosh" when at TDC.

 

Auto parts places and some of the online stores (e.g., Summit) sell a TDC tool that screws into the #1 spark plug hole. I think its basically a spark plug with the center electrode replaced by a metal rod that touches the piston. The rod moves up and down with the piston and you just look for the highest point in the travel.

Bruce

The correct way to use a TDC tool is to screw it into the #1 plug hole and turn the stop in. Rotate the crank by hand until it comes against the stop. Make a mark on the balancer where the timing pointer shows. Now rotate the engine by hand in the opposite direction until the piston again hits the stop. Mark that position from the timing pointer on the balancer. Find the mid-point of the two marks and mark you balancer as that is the exact TDC