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I have a 1972 351c motor and I want to make sure the rockers are adjusted properly. I have hydraulic lifters.. Having #1 piston up on compression .Both valves closed.
One person said on Hydraulics --at that point you just torque the rocker to 20 ft. lbs and that's it. Another person said to tighten the rocker bolt until the push rod turns by hand with a little drag. Which one is correct? Thanks. Suede
 

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Stock 351C, other than the '71 Boss 351 and '72 351HO had bolt down pedestal style rockers, which have no adjustment.
 

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Take each rocker off and make sure the pushrods are straight. Roll them on glass. Check the rockers and put the parts back in their original location. It's easy to take the intake off and check the lifters. Mine were in great shape at 120000 miles. But the intake valves were loaded with what looked like tar.
 

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I have a 1972 351c motor and I want to make sure the rockers are adjusted properly. I have hydraulic lifters.. Having #1 piston up on compression .Both valves closed.
One person said on Hydraulics --at that point you just torque the rocker to 20 ft. lbs and that's it. Another person said to tighten the rocker bolt until the push rod turns by hand with a little drag. Which one is correct? Thanks. Suede
I just rebuilt my 351 and went through the same thing the same question. I manually tightened them down each time I turned the crank. Just over hand tight. Once the motor was running I noticed some losing up. With engine running and with covers off I tightened the ones that were not fully tight. But it didn't seem to matter how I started or did it, as there is no lash adjustment on these. So all the talk about tightening a little until no drag...I don't think matters. Mine are all torqued down. The same. Not sure what the torque was, but I'm sure they are all tightened until they won't tighten any more and then some.
 

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Yep, that's it.

If you want to get technical, you can check for lifter travel from the zero lash point. Turn the crank so it's at #1 TDC position. While spinning the pushrod on #1 intake or exhaust, slowly run the bolt down til you feel it take up any clearance. That's the Zero Lash point. Now count the number of turns it takes to bottom the bolt on the fulcrum stand. You should have between 3/4 and 1 3/4 turns. If you do, your pushrods are the correct length. After that, turn the crank 90° and repeat through the firing order (13726548) turning 90° for each cylinder. When you're finished, go back and torque all the rocker bolts to 18-22 ft lbs.
 
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