TDC..........one more time!!!
Thread Starter
Instructor
Joined: Dec 2002
Posts: 174
Likes: 1
From: brandon florida
TDC..........one more time!!!
I got the timing chain installed and rotated the crank 360 degrees and checked the #1 piston and it was at TDC and the distributor fell right into place at the #1 tower!
Now the fun of adjusting the valves begins and maybe i'm a little paranoid at this point
but i want to be sure #1 is at tdc compression stroke! Keep in mind that the rocker arms and pushrods have been replaced! I still have the timing cover off so if i rotate the engine and align the timing sprocket dots at 12 o'clock can i be sure that #1 is tdc compression stroke? I know the lifters should be down #1, what cylinder's lifters will be moving as i rotate the crank right before #1 is coming up? With the trouble i had the first time i guess i'm a little gun shy 
in doing this, so once again i'm aking for assistance!! 
Now the fun of adjusting the valves begins and maybe i'm a little paranoid at this point
but i want to be sure #1 is at tdc compression stroke! Keep in mind that the rocker arms and pushrods have been replaced! I still have the timing cover off so if i rotate the engine and align the timing sprocket dots at 12 o'clock can i be sure that #1 is tdc compression stroke? I know the lifters should be down #1, what cylinder's lifters will be moving as i rotate the crank right before #1 is coming up? With the trouble i had the first time i guess i'm a little gun shy in doing this, so once again i'm aking for assistance!!
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
With the dots together your firing on # 6. Rotating the cam gear so the dote is at 12, {straight up} then the ignition firing is # 1. Both #1 and #6 pistons are always at the top of the stroke the same time. After that adjusting the valves are easy. You can do one cylinder at a time by just watching the valves opening and closing. As the intake starts to open, adjust the exhaust, and as the exhaust starts to close adjust the intake. Then go to the next cylinder and repeat the proceedure.
Instructor
Joined: Jun 2004
Posts: 233
Likes: 0
From: algonac michigan
relax its not that critical...most of your cam is not lift/lobe
get it close and then adjust #1
then rotate crank 90* and go to next cyl in firing order
continue this....rotate 90* adjust thru firing order and you are done.
to get zero leash...
some do it by feel, rotating the push rod
i couldnt get the feel for it so i looked for movemont up-down
once its gone tighten additional 1/2 turn
good luck
get it close and then adjust #1
then rotate crank 90* and go to next cyl in firing order
continue this....rotate 90* adjust thru firing order and you are done.
to get zero leash...
some do it by feel, rotating the push rod
i couldnt get the feel for it so i looked for movemont up-down
once its gone tighten additional 1/2 turn
good luck
Thread Starter
Instructor
Joined: Dec 2002
Posts: 174
Likes: 1
From: brandon florida
76redstinger
No matter how many times i rotate the the crank by hand, all i have to do is align the dots, crank and cam at 12 o'clock and i'm at tdc #1 compression stroke? From here i start adjusting the valves, i too tried to do the twirl/feel method for adjusting them the first time with no luck! I had also heard of the method you described, moving the pushrods up and down, that is how i am going to do it this time. Thanks for the advice! 
No matter how many times i rotate the the crank by hand, all i have to do is align the dots, crank and cam at 12 o'clock and i'm at tdc #1 compression stroke? From here i start adjusting the valves, i too tried to do the twirl/feel method for adjusting them the first time with no luck! I had also heard of the method you described, moving the pushrods up and down, that is how i am going to do it this time. Thanks for the advice!
Melting Slicks
Joined: Aug 2004
Posts: 2,063
Likes: 1
From: Beverly Massachusetts
the easiest way to make sure you got the cam dead on is align the dots and you should be good to go. then adjust your rockers and then rotate the motor over till you get the #1 cyl to top dead center. you can feel for the air rush on the #1 spark plug hole and also by looking for both valves to be closed and the timing mark on the damper to be at 0 then you can drop your dist. in with the rotor pointing to the #1 position on the cap. you cant miss. i know it sounds like that can take a while but if you want to finish fast you have to go slow
Melting Slicks
Joined: Jan 2004
Posts: 2,527
Likes: 1
From: St. Petersburg, Fl///Columbus, Ohio
My "trick" for TDC works every time on a new engine.... Before I install the plugs, I Tighten the rocker nuts on #1 cyl so 3 threads show above the rocker nut.... then I turn the engine over by hand while a helper stickes there finger in #1 spark plug hole.... You'll hear the air pushing past there finger on the compression stroke.... Stop at TDC.... Loosen the rocker lock nuts turn the engine 90deg and START with #8 .... Adjust #1 last & you'll finish on TDC
DO NOT double check the lash.... you'll just make it too tight!!!
I use the "spin" method myself ..... It's what my GM books say to do.
If you rebuilt your engine 1/2 turn on the rocker nut after you can't spin
roller cams (newer engines) seem to like a full turn better!!
DO NOT double check the lash.... you'll just make it too tight!!!
I use the "spin" method myself ..... It's what my GM books say to do.
If you rebuilt your engine 1/2 turn on the rocker nut after you can't spin
roller cams (newer engines) seem to like a full turn better!!
