avengedws6

iTrader: (15)

A friend of mine called me today and said something didnt feel and sound right in his car, so he took the valve covers off and had someone bump the key to turn it over, and he called me saying that the rockers only move about an 1/8th of an inch. If the cam is flattend, what could cause that? Im thinking lifters or pushrods. Just been puzzled on this.

whitehooptie

iTrader: (2)

Uh, roller lifters dont flatten. Flat tappet cams do. What kind of car is this on?

avengedws6

iTrader: (15)

Its a Camaro SS with a LQ4 in it.

whitehooptie

iTrader: (2)

Have him pull the valve covers and see if a pushrod is bent.

avengedws6

iTrader: (15)

I think he's gonna look at those next. Thats what I think wrong length pushrods.

1_fast_gto

iTrader: (1)

we have been seeing camshafts flatten at the dealership lately but there is usually a tick noise or squeak noise accompanied with it, if he doesnt find a bent pushrod hes gonna need to take the heads off to inspect the lifters and camshaft....

Greed4Speed

iTrader: (7)

They sure do if the lifter messes up or the lobe wasn't properly hardened.

I have had lifters collapse and round off lobes, and IIRC there was a bad run of Futral cams several years back that weren't hardened that was having flattened lobe issues.

Greed4Speed

iTrader: (7)

First thing I'd check is if the rockers are torqued to spec. I believe stock pushrod length is 7.4". If they're after market they'll probably have the length on the side of the PR. If they're bent he can tell by rolling them on a flat surface.

1 fast GTO is right, he'll have to pull the heads to check the lifters. Too bad GM didn't put an inspection panel in the valley tray.

whitehooptie

iTrader: (2)

The only thing I have seen is a lifter malfunction of some sort happens, grinds all of the hardened material off of the cam and take chunks out. But I guess there is a first time for everything.

Bad Blu Formula

iTrader: (3)

It would be hard to believe that all the lifters would collapse or that every pushrod would get bent. I had never heard about a cam's base metal not being properly cured, but its sounding like that may be the case here.

blk90coupe

iTrader: (1)

I've had three litters fail at once, resulting in three flatened cam lobes lol....

Bad Chad

iTrader: (94)

Before he goes through the trouble of pulling the heads tell him to cut open his oil filter and look for excessive metal shavings in it. If the filter is clean then I doubt it will be a flatened cam.

ramairracer

iTrader: (13)

1fast gto is right here at the dealership we've seen a rash of 07+ 5.3 lifters eating into the camshafts

avengedws6

iTrader: (15)

Thanks for all the info.

gtslo88

iTrader: (1)

I just had a lifter collapse and flatten my cam out a bit.. sad day for the gto, also an expensive one