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Dual quad · 01-21-2005, 08:26 PM

You need to check that the rocker is acting upon the central section of the valve stem. The rocker actually wipes across the valve stem tip as the valve operates. If the pushrood is either too long or too short, this valvetrain geometry is compromised.

One of the ways you can do a quick check is remove a rocker and mark the valve tip with a black marker. Reinstall the rocker and turn the motor over by hand (might want to remove some plugs first). You can then remove the same rocker to see the witness marks. The marks should show action centered around the middle of the tip.

You also might want to take close look to see that the rocker is actually pushing down on the stem tip only and not part of the retainer.

BTW, I'd like to see a pic of your truck with the wheels and drop.

01-21-2005, 08:26 PM	#4
Dual quad Smell that burnin' rubber Join Date: Sep 2000 Location: Ontario Posts: 171	You need to check that the rocker is acting upon the central section of the valve stem. The rocker actually wipes across the valve stem tip as the valve operates. If the pushrood is either too long or too short, this valvetrain geometry is compromised. One of the ways you can do a quick check is remove a rocker and mark the valve tip with a black marker. Reinstall the rocker and turn the motor over by hand (might want to remove some plugs first). You can then remove the same rocker to see the witness marks. The marks should show action centered around the middle of the tip. You also might want to take close look to see that the rocker is actually pushing down on the stem tip only and not part of the retainer. BTW, I'd like to see a pic of your truck with the wheels and drop. Last edited by Dual quad; 01-21-2005 at 08:30 PM.