Working on the '87 305 motor, that I put in my S10 with an LT1 cam. The #8 cylinder seems to have a ticking sound. Adjusted the valve lash with the engine running. The intake valve was a little loose, and the nut spins very easily. Replaced the nut, and the ticking went down a bit. It's not pushrod to rocker clacking. And it doesn't seem to be loud enough to be a bearing. How do I tell that this is a collapsed roller lifter without taking the intake off? Thanks -Paul

with the engine off, take the push rod and push it down, you should feel spring action from the lifter. thats the only way i can think of.

Basically, lifters don't "collapse", because they can't. There's nothing in a lifter to "collapse". "Collapsed lifter" = street slang for "It makes a noise and I have no idea what's causing it or how to find it".

Take a piece of heater hose and stick it in our ear (I just love telling people to do that!!) and see if you can pinpoint exactly where the noise is coming from; the rocker tip, the push rod end, the rocker ball seat, etc. Swap the rocker and push rod from the noisy valve with a quiet one and see if the noise moves. While you have it apart, inspect the rocker very carefully; look for a groove in the tip where it meets the valve stem, make sure the ball is spinning not sitting still in the rocker seat, etc; roll the push rod on a piece of glass, if it goes "tick-tick-tick" as it rolls, it's bent; look very carefully at the valve spring, check for a broken damper or a shim that's cut all the way through; etc. etc. etc.

If the noise stays on the same valve, it's a spring issue, or the cam lobe or lifter roller is damaged.

What about the valve seat? Friend and I came up with that idea too.

I'll try moving things around tomorrow.

I suppose a compression check (if i had a working gauge) would tell me if it's a seating problem...

You can have a "collapsed lifter" what happens is the check valve in the lifter refuses to hold oil.Usually this is caused by a spec of something getting caught in the valve. When this happens the plunger that the push rod rests on is held up only by the spring inside the lifter. The plunger is supposed to be held by oil retained in the lifter body instead. This makes the hydraulic lifter self adjusting. A lifter that has been run in a vehicle should be hard when you press on the push rod. If its real easy like pushing against a spring, then it has a problem. Blockage of the oil passages can also cause this.


The points RB made are also valid.. Check everything.

I moved the rockers/ball/nut/rods from cylinder 2, to the problem cylinder #8. Still made the sound. Replaced the lifter. Still ticks.

When I tighten the rocker nut from the set lash 1/4 turn, it goes away for a few seconds and comes back, same with loosening it 1/4 turn.

It's the Intake valve on #8.

So valve seat or spring or what?

Probably the spring.

Here is a guess, is the rocker stud pulling out of the head when you adjust the lash ? You said that the lash was loose when you checked it.

RB brought up the possibility of a damaged roller or cam lobe, that is something to check.

I've seen diesels waste multple cam lobes because of a damaged roller.

Good luck.

The stud is not pulling. I know this for a fact because I had studs pull on my Iroc, and have much experiance with that now.
Not sure about the cam lobe, or how to check that without pulling the cam out.

However I did replace the lifter with a brand new roller lifter, and it still does the same thing. The sound is definatly coming from the rocker/spring area.

I inspected the camshaft when I put it in and it looked fine to me. Ran this for 2000miles before this sound.

Upon inspection of the replaced lifter, the roller looks fine and spins freely, and I cannot push the plunger down.

thats BS cuz they collaspsed on me when i had the timeing chain on the wrong mark and went to set the valve lash and POP i collapse 6 of them. now on a roller cam i don't know

How are the valve guides? Are they worn?
I would do a cylinder leak down test to check for a damaged valve.

mine are brand new :-D the motor and heads and everything where just rebult 2,000 miles ago

you know man, i'm having the same problem. i should have it fixed by the end of next month(i only have maybe 1 day a week to work on it.)
what am i doing, you ask?
taking off the tpi intake, selling it for lt1
taking off the heads, putting on complete aluminum l98's
doing a cam/lifter swap.



it may not be the best way to figure out whats making the noise, but it is a good excuse for more go fast goodies.

I would think the spring first, like already mentioned, but then after that, if it is still a problem. Being that it is #8 cylinder, and I see this alot. If you, or anyone over tightened the rocker it can and will wear out the bottom of the lifter, allowing the spring and all to fall into the engine, now this is worse case senario, but I have come across it often on peoples cars/

I replaced the lifter with a brand new one, so that can't be it.

I will ATTEMPT to take the spring off now. .....

if you do one you should do them all. and if you takeing off the sprinf you may as well put new vavle seals in .