I had a small rattling noise under my valve cover (driver side by the firewall). I though the exhaust or intake rocker arm could probably stand some adjustment. After I had gotten the intake valve up all the way, I was able to move the push rod slightly up and down so that it clicked. I adjusted the rocker arm for zero lash, tightened the locking screw. Just after doing that, found that I could still move the the push rod up and down the same as before. I adjusted again and tightened. Same thing again. I could move the the push rod slightly. I ended up doing that 5 or 6 times. Then moved on to the exhaust rocker arm. That had less play but I tightened up anyway. Checked some of the others but none had any play like that one. I buttoned up the valve cover and replaced the intake etc.... Started the car and it idled much rougher than before. I can still here the small rattling noise just has it had been before I adjusted it.
Do you think the lifter is bad and I just tightened the rocker arm too much causing the valve to stay open or something? The car has 160K on it and I never changed out the original lifters although the rest of the valve train has only 30K on it. I did notice that when I twisted the push rod around (like they tell you to do when adjusting the lash), it would get stiff and then easy -- possibly slightly bent? The push rods are relatively new and the hardened type. I'm kicking myself for not changing out the lifters when I had it all apart installing the heads! Anyone have any experience with this?
Is this the car with scorpion rockers and tw 170's?
How was the pushrod measured and how did you set the valve lash the first time?
Right at zero lash and just a tad tighter (maybe 1/8 of a turn). Yeah same car.
You tighten it ONCE, if lifter bleeds down so be it, should be OK with oil pressure... Now it's no doubt too tight...
Back in old days we always adj with engine running... Tighten till click stops and then another ¼-½ turn...
no doubt. but I guess the rattle is still a mystery. I'll crack it open again and readjust. Thanks for the advice.