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I'll have to take off all intake and exhaust rocker valves to replace the support stand. Question for you all-in order to do so I'll need to make sure engine is rotated to TDC. Right now (right bank), cyl #2 exhaust valve is what's being worked on-without the timing cover off, how do I verify cam/crank position? I looked at the harmonic balancer and see that it's got 4 sets of dots around the circumference in a pattern like o oooo oooo o but I'm not sure what these marks refer to.

View attachment 500184

Instead of looking at dots I may be able to rotate the crank and follow the movement of one of the pushrods.

Thanks
if you want to find #1 firing position, take the plug out of #1. stick something in there so you can feel the top of the cylinder. rotate the engine until the piston is at the top of the cyl, and make sure the intake and exhaust lifters are in the base circle. if the rocker arms are off, you can just watch the height of the pushrods.
 

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Can I inspect for a bad lifter without pulling the head by replacing support, rocker arm, pushrod and checking to see if the rocker arm then has play i.e. it looks like I can substantially vary the lash?

Thanks!
i've never had a bad lifter before, but I can tell you how it SHOULD act.

when you install a rocker, making sure the associated lifter is on the base circle and not on the lobe ramp, as you get close to seating in the rocker stand, the valve spring will compress a little, opening the valve slightly. there will be no play in the pushrod or between the rocker tip and valve tip.

after a couple of minutes, the lifter seems to bleed off and the plunger and cup settles in the preload position. that valve will now be closed and the spring has uncompressed. you should have zero lash and the pushrod, and between the rocker tip/valve stem tip. if you have aftermarket trunnions, you should now be able to wiggle the rocker SIDE-TO-SIDE, BUT NOT BACK AND FORTH. So, i would think if you have play where the pushrod goes into the rocker cup, or between the rocker arm and valve stem end, you might have issues.
 

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Why do you need to only tighten down the rockers when they are on the base circle? They are not adjustable, so tightening them down wherever they are would seem to accomplish the same thing as tightening them down when they are on the base circle. I mean, if you're tightening down a rocker where the lifter is at the top of a lobe, it will simply open the valve as you tighten the rocker down, right? Which is where it would have been anyway before you removed the old rocker.

Is the base circle thing so you can get the rocker bolt torque correct?
 

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Why do you need to only tighten down the rockers when they are on the base circle? They are not adjustable, so tightening them down wherever they are would seem to accomplish the same thing as tightening them down when they are on the base circle. I mean, if you're tightening down a rocker where the lifter is at the top of a lobe, it will simply open the valve as you tighten the rocker down, right? Which is where it would have been anyway before you removed the old rocker.

Is the base circle thing so you can get the rocker bolt torque correct?
i've tightned the rocker arm the way you describe in the past and haven't had an issue. i don't do that anymore. but yes, i do want to make sure most if not all of the 22 ft lbs goes into fastener clamping force and not compressing the valve spring, lol.

in op's instance, it would be good for testing to see if the lifter is collapsed or not.
 

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I found some rocker instructions somewhere just now that said to absolutely NOT remove a rocker when the valve is open to avoid messing up the rocker bolt threads. I guess that make some sense too since there is a lot of pressure against that bolt when the valve is open and the threads are in aluminum not steel or iron.
 

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I found some rocker instructions somewhere just now that said to absolutely NOT remove a rocker when the valve is open to avoid messing up the rocker bolt threads. I guess that make some sense too since there is a lot of pressure against that bolt when the valve is open and the threads are in aluminum not steel or iron.
sounds like wise advice.
 

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Discussion Starter #28
Still waiting on a couple last parts to arrive. Did order a new lifter and will inspect when parts arrive (obviously eggs in one basket that cam isn't beaten up) during teardown/rebuild.

Thanks for contributing to the thread. I do see what you guys are saying about not removing rocker bolts when valves are open and it makes intuitive sense. It is curious that the manual I've been looking at does not mention this detail-it is only concerned about the bolt tightening operation.
 

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Discussion Starter #29
Question for you guys. After getting parts in and starting to dig into the car the intake manifold is off. I want to take off the valley cover but one of the (think they may have come with the FAST manifold) button-head hex bolts is stripped out pretty bad. Without being able to weld, what are my best options for getting this bolt out?

500505


I have two thoughts at the moment:
1. Apply some penetrating oil on this bolt, and
2a. JB weld the 5mm allen to the bolt or
2b. Use a disc and cut an opening for a flathead or cut the sides off and try to turn with visegrips.

Thanks,
 

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You might try wasting a torx socket that is a little oversized to that allen hex slot in that socket bolt, tap in in there and then ease it with a 3/8ths breaker bar while applying pressure to keep it seated with the palm of your hand over the end of the bar.

I've gotten them out that way. As long as you can break it loose, you should be golden.
 

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Craftsman (and I'm sure others) makes a set of special screwdriver bits that are like a phillips head but the blades are tool steel and angled kind of like a drill bit. Point is, you put it in the worn out head and as you turn it digs in and hopefully breaks the bolt loose. I've got a set but I've never had an opportunity to use them. However, the bolts that hold the shifter knob handle to my Billet Pro shifter have the same problem, I just don't have any need at the moment to remove them.
 
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