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Rocker/Pushrod Install Question

Old Jan 26, 2013 | 07:32 PM
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Default Rocker/Pushrod Install Question

I have a question, I know the recommended pushrod/rocker install is the following procedure:

Rotate the crankshaft until the number one piston is at top dead center (TDC) of the compression stroke. In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5, and 7 are left bank. Cylinders 2,4,6, and 8 are right bank. Notice: Refer to Fastener Notice in Service Precautions.

7. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
a. Tighten the exhaust valve rocker arm bolts 1,2,7, and 8 to 30 Nm (22 ft. lbs.).
b. Tighten the intake valve rocker arm bolts 1,3,4, and 5 to 30 Nm (22 ft. lbs.).

8. Rotate the crankshaft 360 degrees.

9. Tighten the following valve rocker arm bolts:
a. Tighten the exhaust valve rocker arm bolts 3,4,5, and 6 to 30 Nm (22 ft. lbs.).
b. Tighten the intake valve rocker arm bolts 2,6,7, and 8 to 30 Nm (22 ft. lbs.).
Now, I see many other write ups and threads where the pushrods and rocker arms are put in and then the bolts are just torqued to 22 ft-lbs without following the specific procedure above.

Is the procedure above really necessary? My timing cover is on so I won't be able to verify the timing markings anyway? I guess with the pushrods in I can see if cyl 1 is at tdc, then spin it 360 to follow the procedure?
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Old Jan 26, 2013 | 08:33 PM
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Originally Posted by snyousef
I have a question, I know the recommended pushrod/rocker install is the following procedure:



Now, I see many other write ups and threads where the pushrods and rocker arms are put in and then the bolts are just torqued to 22 ft-lbs without following the specific procedure above.

Is the procedure above really necessary? My timing cover is on so I won't be able to verify the timing markings anyway? I guess with the pushrods in I can see if cyl 1 is at tdc, then spin it 360 to follow the procedure?


The reason being is so you get an accurate torque and not strip the threads in the head if the valve is at max lift. I just rotated the engine over until the particular lifter was all the way down and installed the rocker. Once I had them all installed, I spun the engine over and check them over.
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Old Jan 26, 2013 | 08:37 PM
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Hopefully going through this myself tomorrow.
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Old Jan 26, 2013 | 10:19 PM
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Like said above, I wouldn’t just throw them in and torque them, you risk messing up the threads. That procedure you quoted will work fine, but the easiest way IMO is just install all pushrods and make the rockers snug, doesn’t need to be exact. Have a friend rotate the crankshaft. Watch the rockers for cylinder #1, and when both arms stop moving (TDC), remove the rocker bolts, apply thread locker, reinstall the bolts and torque. Do the same for every cylinder. Quick and very easy.
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Old Jan 26, 2013 | 10:31 PM
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Originally Posted by 02DroptopZ
Like said above, I wouldn’t just throw them in and torque them, you risk messing up the threads. That procedure you quoted will work fine, but the easiest way IMO is just install all pushrods and make the rockers snug, doesn’t need to be exact. Have a friend rotate the crankshaft. Watch the rockers for cylinder #1, and when both arms stop moving (TDC), remove the rocker bolts, apply thread locker, reinstall the bolts and torque. Do the same for every cylinder. Quick and very easy.
do you use the blue locktite?
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Old Jan 27, 2013 | 03:50 AM
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Originally Posted by badazz81z28
The reason being is so you get an accurate torque and not strip the threads in the head if the valve is at max lift. I just rotated the engine over until the particular lifter was all the way down and installed the rocker. Once I had them all installed, I spun the engine over and check them over.
Oh ok that's understandable.

Originally Posted by 02DroptopZ
Like said above, I wouldn’t just throw them in and torque them, you risk messing up the threads. That procedure you quoted will work fine, but the easiest way IMO is just install all pushrods and make the rockers snug, doesn’t need to be exact. Have a friend rotate the crankshaft. Watch the rockers for cylinder #1, and when both arms stop moving (TDC), remove the rocker bolts, apply thread locker, reinstall the bolts and torque. Do the same for every cylinder. Quick and very easy.
So for example when doing cylinder 3, rotate until cylinder 3's arms stop moving (TDC) then torque the cylinder 3 rocker bolts? Or are you saying torque all the rocker bolts when cylinder 1 is at TDC?
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Old Jan 27, 2013 | 07:12 AM
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Originally Posted by snyousef
So for example when doing cylinder 3, rotate until cylinder 3's arms stop moving (TDC) then torque the cylinder 3 rocker bolts? Or are you saying torque all the rocker bolts when cylinder 1 is at TDC?
When doing cylinder number 3, put #3 at Top Dead Center, torque it. Move on to the next one. Put that one at TDC, torque it. Your going to put each cylinder at TDC, when working on that particular one.
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Old Jan 27, 2013 | 07:20 AM
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Quote: do you use the blue locktite?


I don't................... But if you have ported heads the holes likely go though to the port
on the intakes. I use liquid teflon sealant on those and trim them so they do not protrude
into the port
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Old Jan 27, 2013 | 10:30 AM
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Originally Posted by sreve
Quote: do you use the blue locktite?


I don't................... But if you have ported heads the holes likely go though to the port
on the intakes. I use liquid teflon sealant on those and trim them so they do not protrude
into the port


I ended up not using loc-tite at all. I used threader sealer on the intake bolts since my heads were ported.

I will go back and check them in the future.
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Old Jan 27, 2013 | 04:30 PM
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Originally Posted by zerogravity779
When doing cylinder number 3, put #3 at Top Dead Center, torque it. Move on to the next one. Put that one at TDC, torque it. Your going to put each cylinder at TDC, when working on that particular one.
Got it, thanks!
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Old Jan 31, 2013 | 06:58 PM
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Can the below procedure be used with a car with a mild cam (228@50 and under .600 lift)?


Rotate the crankshaft until the number one piston is at top dead center (TDC) of the compression stroke. In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5, and 7 are left bank. Cylinders 2,4,6, and 8 are right bank. Notice: Refer to Fastener Notice in Service Precautions.

7. With the engine in the number one firing position, tighten the following valve rocker arm bolts:
a. Tighten the exhaust valve rocker arm bolts 1,2,7, and 8 to 30 Nm (22 ft. lbs.).
b. Tighten the intake valve rocker arm bolts 1,3,4, and 5 to 30 Nm (22 ft. lbs.).

8. Rotate the crankshaft 360 degrees.

9. Tighten the following valve rocker arm bolts:
a. Tighten the exhaust valve rocker arm bolts 3,4,5, and 6 to 30 Nm (22 ft. lbs.).
b. Tighten the intake valve rocker arm bolts 2,6,7, and 8 to 30 Nm (22 ft. lbs.).
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Old Jan 31, 2013 | 07:19 PM
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Yes. That procedure is from GM and when followed ensures that the rocker being tightened is on the cam base circle. There is no need to do one cylinder at a time with stock rockers, simply follow the GM procedure.

However, aftermarket rockers such as Yella Terra are installed in pairs and must be installed one cylinder at a time with each set being installed when the piston is at TDC on the firing stroke.
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