98cobrakillata

iTrader: (2)

Would disconnecting the fuel injectors one cylinder at a time help to eliminate the possiblity of a rod bearing being spun?Because I tried that and started the car doing that one at a time the sound did not change.I was hoping to eliminate the rod bearings being spun.

T/A-Speedfreak

iTrader: (8)

I had to pull the valve covers and look at all my springs and rocker arms(which looked fine). It took me a few minutes to notice that the oil looked to have a grayish color. The grayish color being the metal residue. I could only see the metal on a white paper towel. It doesn't seem like you would/could change the bearings while the motor is still in the car. I followed some instructions from this board on how to pull the motor out the bottom. It was time consuming for me due to the fact that it was my first time but it wasn't hard. There is alot of technical reasons why not to try and replace the bearings yourself and although you might be a fine mechanic, this is the heartbeat of your car and it needs to be done right. I personally would doubt myself and if for some reason something didn't go right the only person to blame would be myself and my scrooge like ways.

98cobrakillata

iTrader: (2)

Just to give who ever cares an update and possible get some more feed back.
I took off the rocker arms and disconnected the injector, on where I suspected the noise was coming from #6 cylinder.I started the car and no noise.I then put the rocker arms on 1 at a time, I noticed the noise was only there with back rocker arm on so I am assuming that it is a bad lifter.Does any one agree or think different?

GuitsBoy

iTrader: (4)

Swap rockers with a quiet one to see if its the rocker itself or a bad lifter. Swap them back the way they originally were when youre done testing. I assume you also pulled the pushrod to check that out?

Ragtop 99

iTrader: (7)

98 Cobrakillata:

was your marbles sound present under all operating conditions or just at certain loads or idle?

I get an occasional marbles sound from what sounds like they are in the intake. It only occurs at low rpm coasting (below 2000 rpm) and not consistently. I don't have any misfires and my oil pressure is good so I've assumed it is tuning related rather than mechanical.

I just wanted to compare your experience to mine and see if my assumption is off.

98cobrakillata

iTrader: (2)

Yes pulled push rods for that #6 also and didn't notice them to be bent.I will try swapping the two rockers and test the rockers also.thx

98cobrakillata

iTrader: (2)

My marble like tapping sound is rpm related, in that it is consistant with the rpms but when I let off the gas it stops until around 1500rpm when it starts again.When we first started listening to the sound it would go away completely and then come back, now it seems to be there all the time except when I pulled the rockers/push rods/injector wires.