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A customer brought a car in that had some pretty bad lifter noise. Other than that, it would start and run reasonably well. After adjusting the valves 3/4 of a turn past zero, the car would hardly run at all. I noticed that one of the set screws inside the poly-lock was set noticeably higher (the poly-lock was screwed onto the stud more than the others). I re-set ALL of the valves, same running issue, same adjuster issue. The car was running too rough to notice if the valvetrain was any quieter than original. If I set the poly-lock in question to look like the others (back off the adjuster by eye), the car will start, idle, and sound as it did originally (bad lifter noise). It seems obvious that the valve was being held open causing the poor running condition. I am 100% certain that the pre-load was set to 3/4 turn past zero lash. This would lead me to believe that the lifter is collapsing and staying down prior to adjustment, then pumping up when the engine is running and holding the valve open. I have never experienced this before. Is this a "collapsed lifter" or something else? Does the lifter need to be replaced or is there a way to save it? Here is the combination...

3.8L Buick V6 (Grand National)
Chapman Stage 2 Heads
Hydraulic roller camshaft (~224* @ 050 range, unknown lift)
Morel (we believe) hydraulic roller lifters
Scorpion roller rockers on 7/16 studs
Poly-locks that came with the Scorpion rockers
Unknown valve springs, steel retainer

15w40 weight (unknown brand) oil originally when car was brought into the shop
10w40 Redline oil in it now after first valve adjustment
Engine shows 70-80 psi oil pressure at moderate RPM
 

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Some lifters feel a lot more 'solid' without the engine running than others. Some you can squish right down to nothing, and some feel solid as a brick. You can replace the lifter, or be careful when setting the initial lash/preload. Gently twist the pushrod between your fingers while tightening the adjusting nut. As soon as you feel the slack get taken up, add another 1/4 to 1/2 turn, and call it 'good'. Don't wait until the pushrod gets hard to turn. Just go until you feel the slack get taken up. Hopefully, this will help with the valve being hung open. Don't know what to say about the noise.
 

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Discussion Starter #3
Some lifters feel a lot more 'solid' without the engine running than others. Some you can squish right down to nothing, and some feel solid as a brick. You can replace the lifter, or be careful when setting the initial lash/preload. Gently twist the pushrod between your fingers while tightening the adjusting nut. As soon as you feel the slack get taken up, add another 1/4 to 1/2 turn, and call it 'good'. Don't wait until the pushrod gets hard to turn. Just go until you feel the slack get taken up. Hopefully, this will help with the valve being hung open. Don't know what to say about the noise.
Thanks for the response, but this isn't the issue. Intake will be coming off later this week to take a closer look at the lifters and camshaft.
 

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I have had some bad experiences with the morel hydraulic rollers. But, have not had any from Crower give me any trouble. Something to consider.
 

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There are going be 'bad' lifters in all makes because they are being tasked to handle forces faaaaaaaaar greater than Harley Davidson envisaged when they first used them in 1929.........
 

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Talk them into some Johnsons. I'd cut the oil filter open to make sure it's not making debris somewhere.
I would also replace all the valve train hardware - rocker studs, bolts, poly locks.... pick the right studs to get a lot of thread engagement. The guy that owns Jomar showed me a lot of hints to keep a poly lock system surviving - need to keep the hardware fresh. Lots of thread engagement, correct geometry, and keep the hardware fresh. As threads age, they loosen up. As they loosen up, shit breaks, shit goes out of adjustment easily. On my BBC with ancient Jomar stud girdles, if I change the rocker studs, poly locks, and bolts in the girdles... it holds valve adjustments great. If those poly lock/stud threads get the slightest looseness, junk them. I broke a poly lock once, and Jomar felt my other ones and said - way too loose, keep these fresh. They were probably 5 years of racing on them, and the threads had a slight looseness. New poly locks should spin on the stud threads with no wiggle. A lot of people think that cranking the allen center tight will cure that. Nope, that's a bandaid that will fall off.
 

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Yep. Pulled the intake off today and found a bad lifter. Wheel still looked ok, but something inside was definitely not right.
There have been a lot of complaints in the last couple of years concerning Morels hydraulic lifters. I am sure you can search the internet and this forum to find several, the most common solution has been switching to Johnson's.
 
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