97 Dodge 5.2-replaced cracked head with heads from 97 jeep cherokee 5.2. Everything went well except when we torqued rocker stands all valves seemed to open before reaching spec. Trying to avoid bent valves. Need help with installation procedures.

 

I answered your last post on this. With the cam, lifters, and pushrods installed, some of the valves are going to be open and some will beclosedwhen you torque the rockers down. The motor would not start otherwise. Also lifter pump up will account for a slight bit of valve opening when you torque them down. For piece of mind you can unplug the pcm ( this will disable fuel and spark ) and crank the motor for about 10-15 seconds with the starter. This will bleed the lifters down.

 

We appreciate your help, however even valves with lifters down are opening and wonder if there should be some valve lash? Thanks again!

 

You can also do this for piece of mind:
Turn the crank by hand to#1tdc. Both valves on #1 will be closed. Torque the lifters. The valve springs should compress very little or not at all.
Turn the crank 90* to the next slot on the balancer. This represents the next cylinder firing (8). Tighten those rockers. Same thing- valve springs should compress very little or not at all.
90* more to the next slot- tighten the rockers on cylinder #4
and so on.........
Firing order is 1-8-4-3-6-5-7-2

 

Thank you for your assistance....we are on it!

 

There is no lash on a hydraulic valve train. The lifters adjust themselves, and the rocker will exert a small amount of force on the valves even when they are closed. Use the procedure I outlined before. Then turn the crank by hand to assure yourself that the valves are not hitting the piston tops. Then crank the motor with the starterwith the fuel/spark disabled. This will bleed the lifters down to where they should be.