well this noise came shortly after one of my rockers came loose and came right off the stud and was laying under the valve cover, it knocked, then after the rocker went back on set valve lash nice and very tight, motor ran perfect and strong, oil gauge is fine, but now im getting this, kind of sounds like a piston slap but i'd like to be sure, any ideas?


http://videos.streetfire.net/Player....C-BABD655B3AB8

 

sounds exactly like a loose lifter to me.do you have screw in studs?poly locks?
Eric B

 

yes i have screw in rocker studs, and poly locks, im running comp cam pro mangum 1.6 roller rockers

EDIT: only odd thing is the very last rocker on the driver side is higher then all the others, sometimes i cant even get the polylock on would this be in cause of a loose lifter.

 

might double check that the pushrod on that valve is fully seated in the lifter cup?
if not,i'd replace that pushrod before starting the engine again.
Eric B

 

well they only sit in one way dont they, why would i need to replace the pushrod?

 

sounds like a pushrod to me... either way I would not rev or run that thing any until i was about to replace the pushrods and check the lifters.... something like that could waste a motor in short order

 

ok i wont run it, ill check the pushrod like you would check a pool cue. also, how do i know if its a lifter how do i check?

 

a pool cue type sheck is good.. i ussually use a nice piece of glass to roll it on lol.. can't get to much flatter than that. and also makes a nice clicking sound if it is slightly bent. lifters. i dunno really.. when ever i had one fail it was pretty seeable... like the seat was missing from one of them. if they are hydrolic you could tell if it is not pushing oil.. but that is not advisable.. probably wouldn't hurt to check the one that corresponds to the rocker that fell off.. as it would more than likely be the culprit... (these things need a spell check lol). But like i said i am not positive.. ussually when i check i check them all.. had one that looked fine from the top that had half the bottom (where the camshaft hits) completely gone. Pulled the engine the next day ... going to have it cleaned out and checked and then a new cam set and lifters and such will go in.

 

lifters should have a slightly convex shape to the surface that contacts the cam,like this when two are held together. )( .
if they are flat or concave (),they are bad.
Eric B

 

well if you dont know, i dont.

im pulling the intake anyway to put new gaskets so i will check the lifters, to see if they all look the same of it its cracked or where the pushrod seats is ****ed up. i dont know how to tell if a lifter is up too high, down too much, if its loose i dont know how to tighten it, can someone shed some light.

 

ussually a lifter will set right down all the way into the bore unless tyhere is something wrong with the lifter bore i have never heard of one being loose..... unless either the bore was cracked, or if the lifter was completely destroyed....

 

ok well lets doubt its a lifter then.

what if its not the rocker stud pulling out, or a bent pushrod, and the pushrod is sitting in the middle of the lifter in the cup.?

 

collapsed lifter spring?

 

what is a lifter spring, is it underneath the lifter?

how do i get the lifter out to see? how would i know if its the spring?

 

the lifter has a sping inside it.(part of the plunger) . it is what the cup on the top of the lifter is attached to.. ussually when a lifter collapses the spring on the inside of it has come apart.. pretty easy to tell most times since the lift will fall apart if you turn it upside down most times.. also there is a retaining slip on the insdie area of the lifter that hoold things in.. it can break.. with a rocker coming off.. it should have done any number of things including hitting the lifter out of the bore so it is not seated right.. really.. if you take a lifter out.. and compare it with another one.. you should easily be able to tell if it is bad or not.

Somewhere around here i have a bookmark that shows the internals of a lifter....

 

ok ill see if any of them are looking out of the ordinary, how do you take a lifter out?

 

Maybe the same thing
Here's that link
https://www.thirdgen.org/techbb2/sho...hreadid=339080

 

my motor doesnt any skips at any certain RPM, it sounds like it shoot when i give it a shot of gas, and taking it for a spin it works better then i thought it would.

 

If all the parts look good and you find nothing wrong, turn the motor over by hand and watch that valve/rocker... see if it has the same range of movement as the rest. If not, you could possibly have a wiped cam lobe.

 

and hope it is not a cam lobe.. but you are half way there if it is if you have pulled the top of the engine apart...

 

ok so once the intake is off, i should turn the motor over by hand and watch it, if it doesnt go up and down, then its a cam lobe, and i gotta get a new cam, well thats not a BIG deal, cuz i want to put in a bigger one anyway.

 

well taking off the intake, i checked all pushrods, 3rd one from the end on the driverside i can move the pushrod up and down about 1/2" or more, i think that is the culprit, thank *** its nothing serious, and i hope its an easy fix. now for the blue smoke!

here is a picture, the holes in the left and right corners, are these suppose to be there?? (yes yes getting milky oil again unless it never fully drained the first 2 times)

 

i do not remember holes in those places on any engine i have worked on (although i have just worked on the SBC blocks. not the ls1 or lt1 or the like) Looks like they should not be there by the fact of how jagged they are.. if it was supposed to be there you would think it would be a smooth bore. Also, why are you getting the milky oil? where is that coming from?

 

Not sure what holes you're talking about.... all the holes I see, look totally normal... I see the coolant passages in the heads (remember, the heads are identical, and if the head that's on the left were on the right, the hole that's at its rear would be at the front), I see the drainback holes against the back face of the block by the dsitributor, and I see milky oil.

Maybe circles around the holes you are unsure of, would help.

If I was the guessing kind, I'd guess it would be REAL WORTHWHILE to examine your intake gaskets REAL CLOSELY.

 

ko well you explained it sofakingdom, the 2 holes in the back by the distributor hole, they seemed to have chipped away alittle around the edges, but used to be perfect cirles so thats good.

i got new gaskets, so im gonna make sure i get them on right

any tips on putting them on?

 

Not necessarily a cam lobe... if it doesn't go up and down, it could be a cam lobe, or a bad lifter, or a bent pushrod. If the pushrod is straight and the lifter checks out, and it doesnt move as much as the others, then its likely a cam lobe. But check the lifter(s) first.

 

Those two holes that look broken? Those are supposed to be there, they are oil drainback holes. They just have ALOT of casting flash like mine did.

 

ok well im pretty sure everything is ok, the pushrod is straight, everything checks out ok, ill turn it over by hand just to be sure, but would a rocker about to fall off cause that? i could lift the pushrod up and down about 1/2"

 

if a pushrod has that much play in it. yes, that will cause the noise.. it would be the pushrod slamming up and down.... ussually how a pushrod goes through a lifter when an engine is reved up under load....