my car is making a knocking noise. on cyclinder# 2 the second rocker, the pushrod bent in an s shape. so i replaced the pushrod. and i then retorqued it to 22lbs and drove the car for like 2-3 hours off and on. then i heard a little tapping noise, real light. then a little later the engine was knocking. i mean bad and running kinda rough. i just finished a cam and spring change. the cam is a 232 238 .542 .572 112 lsa with 26918 and stock pushrods. the motor is on a stock tune so the rev limiter is still like 6100.the rocker was real loose. i was able to lift it up and wiggle it. also the little hole the pushrod goes into is now larger than before on the head. it is wallered out. so does this mean i need a new head? also what do you guys think caused this. maybe a collapsed lifter. when i free crank the motor the pushrod comes up and down but it doesnt look like it goes as far as the other ones. let me know what you guys think. any help is appreciated.

dan

 

did u replace lifters along with cam/springs? sounds like a callapsed lifter. as for heads, cant say w/out looking at it, post pics.


fuerzaws6

 

no the lifters are stock. well the motor has almost 100k on it so i might as well put new lifters oil pump and chain and gears to while i am at it. i will try to get some pics on here.

 

There is wallered out and then there is REALLY wallered out. If it's just wallered out then you don't need a new head, but if it's REALLY wallered out it's time to get out the credit card. Which one is yours. It wouldn't hurt to change your oil and filter as you probably have some aluminum filings in the pan by now. By the rocker being free to move around like that it allowed the pushrod to gaul the head. Apparently you didn't run the engine for very long with the rocker bolt loose. If you used stock rockers with stock bolts you should have put locktite on the flats of the bolt heads when you installed your rockers to keep this from happening.

 

all the bolts were tight when i took everything apart. so the bolts did not back their selves out.

 

Unless I am mistaken, you shouldn't be using stock pushrods with aftermarket valvesprings. Stockers will just bend under the pressure of the spring.
You need to get a set of hardened pushrods....that in itself might solve your problem.
It also sounds like the bent pushrods are causing the guide to open up.

 

Stock pushrods with an aftermarket cam = BAD idea.

Stupid idea, considering that hardened pushrods are very affordable.

You should have hardened pushrods, along with aftermarket springs, and a ported oil pump whenever you do a cam swap.

 

when i crank the motor over and i hold the pushrod in on the lifter, i can feel a clunk when the push rod comes up. the push rod beside it doesnt do that. what does that mean?

 

anyone???

 

If you only feel the clunk when the pushrod is being raised by the cam lobe you need to look more closely at that cam lobe rather than the lifter. If the lifter were damaged you would tend to sense this problem more frequently than only when that lobe is coming around to actuate its' valve. At any rate that head is going to have to come off and more likely than not the cam will likewise have to be removed. At 100K you should pull both heads. With a bent pushrod the rocker would be free to move when it should be held in position by the valve and rod.