Greetings grampadirt,
Some lifter noises can be fixed with a good cleaning, while other noises will require parts replacement.
The good news is that a collapsed lifter caused by stuck internals is in the former category.
To be a little more specific, here's a good photo of a disassembled lifter:
You must be registered for see images attach
In order to understand where the noise is coming from, the lifter body's position is set by the cam lobe.
The inner plunger sets the position of the pushrod. As long as the plunger can move freely inside the
lifter body while the lifter travels from the top of the cam lobe back to the base circle (valve closing), then it
is this freedom of movement which allows the mechanism to take up any excess clearance in the
pushrod/rocker/valve tip area.
But by the same token, in order for the same hydraulic lifter to stiffen up and act like a 'solid lifter' when the
valve is being opened (ie: from lifter base to top of cam lobe) now it's key for the check valve to seat completely.
If it doesn't, then again there will be excess play when the lifter collapses due to the opposing force from the
valve spring.
In English, debris & accumulated varnish can lead to 'frozen' internal parts, and cause ticky/sticky/collapsed lifters.
With any luck, you will look for and *not* find any excessive wear on the exterior surfaces of the hydraulic lifters
and cam lobes. This will then allow you to carefully disassemble & clean the interior bits, put it all back together,
and then these parts will 'take' a careful preload adjustment. (Similar to scott2093's post referenced above.
Please keep us updated as to your progress and what you discover.
Best of luck --
Let
