98QuickSilver

iTrader: (13)

I bought another LS1 car (this would make number 4, hahah) for relatively cheap in hopes to fix it up.

90k miles, supposedly its never been ripped into or modded, except for an SLP lid and Borla catback.

When I bought the car, the oil pressure at idle was around 20 psi, warm or cold (if the factory ospu is still "good"). The valvetrain was chatty as hell, to say the least.

After getting it home I changed the oil, it was dirty, but no signs of metal shavings in it or the oil filter. Now the factory gauge/ospu is telling me there is 40 psi when I first start the car, and there is absolutely no valvetrain noise coming from the engine anymore... that is, until the engine warms up.

When the engine warms up, the factory gauge/opsu indicates the oil pressure drops to 20 psi at idle. The noise comes back at that point, and seems to be a little louder.

With a stethoscope the noise seems to come around the 2nd cylinder from the front on the passenger side (Cylinder 4 I think).

I need to get a "real" ospu and gauge on the motor, but that's going to have to wait until I decide which one(s) I want to go with.

I'm going to rip off the valve cover today and check the springs, rocker arms, and pushrods in an hour or two.

As for the dropping oil pressure, any guesses?.. oil pump bypass? Infamous pickuptube O-Ring? or ???

Here are some vids, let me know what you think, and maybe some other things to check:




Seems louder inside the car-

KevinR

With the knock and the oil pressure dropping, my guess would be a spun bearing. But, you never know until you dig into it. Good luck.

98QuickSilver

iTrader: (13)

Springs, rockers, and pushrods are fine. I'm tearing the heads off now, then I'm going to take the oilpan off and start reallytearing things apart.

98QuickSilver

iTrader: (13)

Cam bearings are shot. I haven't even looked to see what caused it yet, nor have I tore into the bottom end.

I'm throwing in a 5.3 next weekend until I get another motor built.