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-   -   valvetrain readjustment question (https://67-72chevytrucks.com/vboard/showthread.php?t=219438)

crm318 12-13-2006 02:32 PM

valvetrain readjustment question
 
i have owned my truck for about 3 years now and i rebuilt my motor when i got it. there has always been a valvetrain clatter but no lack in performance at all. i was wondering if i could go back after all this time and readjust the valves to see if i can stop the clatter. would a lifter be all beat up if it was bouncing around in the lifter bore for all this time?

bryanw1968 12-13-2006 05:27 PM

Re: valvetrain readjustment question
 
What kind of rockers are you runnin'?

crm318 12-13-2006 05:43 PM

Re: valvetrain readjustment question
 
all factory valvetrain.

corn 12-13-2006 08:09 PM

Re: valvetrain readjustment question
 
If you have had parts loose enough to bang them around after running it this long you would have worse problems than noisy rockers by now. Id readjust them & see how it sounds. A couple loose ones will name a bunch of noise. You may even have a little more power when you are done. Got to be worth a try... Will you be doing a wet adjust or dry?

Slammed70 12-13-2006 08:29 PM

Re: valvetrain readjustment question
 
Solid or hydraulic?

crm318 12-14-2006 02:06 PM

Re: valvetrain readjustment question
 
it is hydrolic flat tappet. how do you mean wet or dry? my plans was to rotate the motor starting at TDC and adjusting them using the firing order. i will make sure that both valves are closed and take the valve lash out and give them a half turn. what do yall think?

corn 12-14-2006 07:42 PM

Re: valvetrain readjustment question
 
If you do this you will only need to turn the motor over once after you find TDC.

Turn the motor over until you are on 0 deg TDC, (both number one valves closed).

Adjust the #1 exhaust valve
Adjust the #1 intake valve
Adjust the #3 exhaust valve
Adjust the #5 intake valve
Adjust the #7 intake valve
Adjust the #2 intake valve
Adjust the #4 exhaust valve
Adjust the #8 exhaust valve

Now rotate the engine 360 degrees. The mark on the balancer should be back at the TDC mark. Keep in mind that this is not the TDC where #1 would be firing! It's where #6 would fire.

Adjust the #3 intake valve
Adjust the #5 exhaust valve
Adjust the #7 exhaust valve
Adjust the #2 exhaust valve
Adjust the #4 intake valve
Adjust the #6 exhaust valve
Adjust the #6 intake valve
Adjust the #8 intake valve

Your DONE!

A wet adjustment would be to run the engine & do one rocker at a time. Its easier to tell when its adjusted right but IT IS MESSY!...

rage'nrat638 12-14-2006 09:16 PM

Re: valvetrain readjustment question
 
The adjustment for hydraulic lifters is 1 turn down from zero.

In order for the hydraulic lifter to work correctly, it must be centered. . If
your valves have come out of adjustment after several thousand miles of
operation, suspect your rocker arm nuts, and replace them. They do wear out
after constant adjustments.


When adjusting your valves, tighten all adjusting nuts until all lash is
removed by feeling the rotation and up and down movement of the pushrod. Next, set your engine on
TDC #1, pointer at "0". You can now adjust the following valves:


INTAKE on cylinders 1,3,4,8
EXHAUST on cylinders 1,2,5,7


Loosen the adjusting nut until lash is felt by rotating the pushrod. Then
tighten the adjusting nut while rotating the pushrod until all lash is
removed. Now tighten the adjusting nut 1 full turn. This "centers" your
lifter.


After you have adjusted the above valves, rotate you engine 360 degrees
bringing the pointer around to the 0 TDC mark. This is TDC #6. Adjust the
following valves in the same manner:


INTAKE on cylinders 2,5,6,7
EXHAUST on cylinders 3,4,6,8


Your valves are now adjusted properly.

good luck and may the force be with you :metal:

crm318 12-14-2006 10:15 PM

Re: valvetrain readjustment question
 
thanks for the info and the visuals. when i get some free time this weekend, ill give it a shot.


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