I have a 327 hydraulic lifters. When I adjust lasch with motor running the ticking gone I have valves not closing. When I do a static adjustment motor not running I have a good running 327 with a tick. I am looking for advice on a diagnosis. Thank you
Failed / gummed up lifters or cam & lifters . Back in the day,Rislone was the go to for " unsticking" gummed up lifters . YMMV
What you describe sounds very similar to a flat cam lobe. Might check for that. Be careful adjusting valves with the engine running. Easy to screw the valve into the piston...while trying to get a problem tick to quit Good luck!
Causes for lifter noise: Sticky lifters. Try adding a detergent additive like the Rislone mentioned above with your next oil change and put some highway miles on the engine. Or add a bottle of GM positrack additive. It was made to un-stick glazed, varnished posi clutch disks to keep them from chattering. It also worked good at cleaning gummed up lifters. Worn push rods. Check the tips for galling. Make sure they're not plugged so they can properly oil the rocker ***emblies. Worn or cracked rocker arms. Check for wear on the push rod and valve contact surfaces. Also check the rocker pivot balls for wear. Rocker arm studs. Pressed in studs, over time, can slowly start to work their way out of the heads. They'll hold the lash adjustment initially . . . until they don't. More of an issue with new or high pressure valve springs. Worn cam lobes and lifter faces. 'Nuff said.
Check the valve tip end of the stock rocker arms, if the valve tip has worn a groove into the flat pallet end, you get a tick you are unable to adjust out. Valve stem rides on and off the ridge left behind, so you get a random tick.
What process are you using for adjusting the valves? Also check the oil for any "glitter" on the oil stick.
I used to add a pint of MMO to noisy-lifter conditions before doing anything else. Sometimes it worked, sometimes it didn't. I would drive it normal for 3-5 days, dump the oil and filter and install a new quality filter and a multi-grade oil. Then do a conservative running lash adjustment of a 1/2 turn past zero lash.
I agree with adding MMO or some other detergent type additive and driving for a couple hundred miles, if ticking stops it was a stuck lifter great, if not some tear down and inspection will be necessary ,but make sure valves are adjusted correctly as stated above, all good replies. Good luck
Thank you all for taking the time to reply, Rislone Interesting along with a bunch good ideas. I will go start it up to see if writing this post fixed it.
A loose valve guide can cause a tick that can't be adjusted out. With engine running put a side load on the retainer of the valve making noise, hammer handle, ect..
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