4DRUSH

That's a dead hole

pewter99

lifter fail

trust me .....BTDT

Bill Curlee

NO!!! The port is on the BLOCK and it has a plug in it. Look down below that point and a little forward.

If you look hard, you can see it in this picture. That large HOLE on front of the block is the main oil pressure port. Its connected to that hole:



You can easily see it in this picture:



BC


Bill

bnall40

I had a similar pressure drop. Two dealers shops could not come up with the answer. Third dealer mechanic did: faulty oil pump. All bearings worn down to brass metal Pump registered pressure ... Just not enough pressure

radar502

Ticking ? most of the time it's a lifter ,not that hard to find if really loud put your ear close and can here it or put your hand on the rockers and you can feel it or loosen up on the rockers one at a time and the bad one will get really loud .A can lobe may have be going ,Right now is not bad but keep driving and may lead to big prop. It's more than likely in the valve train.. It could be oil pump never check the oil pump with your inside gauge need to check it off the motor to get the real deal if not the pump valve train the cylinders look good rockers look good push rods look good got to go down past the push rods crank shafts don't tick they knock the rods also the only thing I know that ticks is my watch and the valve train in the motor..

ZZ06

Like pewter99 said and ive already said, its a lifter. Or a few of them at this point. Depending on how long u have ran it that way (probably already too late) the cam will be trashed with the lifters. Pull the heads and see for yourself....

racebum

makes sense

at any rate the OP needs to start troubleshooting before it gets really bad. if the lifters have failed to the point you have a drop in oil pressure and cam lobe wear metallic bits are sure to be floating in the oil.

may not have damaged the bottom end yet

address the issue before it does

73Corvette

Hershey71

At 120 K it might be time to pull the motor and freshen it up, or bandage and send it down the road, I'd think twice about the Harbor Freight stethoscope, the sound clarity is poor and it doesn't pick up the small sounds, invest in a Blue Point / SnapOn for about $28 vs the HF @ $5 , your money will be well invested in quality diagnostic tools.

radar502

I have a better idea buy some tools and start working on it .. Just being a smart *** but really there not hard to work on and not giving the man all your money is a good thing .Charge yourself $125.00 hr. labor and you'll be in the rich in know time ..It's all on the net and on this forum just ask we know stuff OK some know stuff some think they know stuff..

About2Bite

Changed the oil and it had a shiny silver look in the sunlight when swirling it around. I ran it thru a mesh screen and didn't find any slivers. I put a magnet in the oil and didn't pick up anything. Still have to pull the intake manifold off.



I'm seeing about a 15psi increase in oil pressure

radar502

After the intake take the valley pan out and you can see the lifters ,look and the cam lobes and if the lobes look good ,you can tell if one is all chewed up or two if all nice and smooth and not eaten up that's a good thing .First thing is find out witch one it is .Take the valve covers off and fire it up find witch side it is and go from there .if you find the side take the valve cover off and feel the lifter wile it's running might be able to feel it if not loosen one at a time and should get louder the bad one will get louder sometimes you can push down on the rocker wile not running and a bad lifter will just feel soft ..

About2Bite

Ok thank you, do you think I could put a telescopic magnet down there and feel play in a bad lifter? By play I mean be able to pull it up and down a bit with the magnet. I'm not sure what actually happens to a lifter when it "goes"

racebum

bearings turn to dust when they get fried. if you starved the bottom end at some point that could explain it all

that haze powder can be bearings, have done that before. tiny little speckles in the oil

you try 50w oil yet and see if the pressure comes up?

About2Bite

No, I put 5w30. I was thinking about sending a sample to blackstone labs to give me an analysis.

Going to take the intake off tomorrow.

racebum

30w really isn't going to show you anything. if you have a clearance issue like bearings thicker oil will help clue you in as it will raise your pressure

if it's a lifter you're still going to knock even with higher pressure. if the lifter is knocking because of the low pressure thanks to excessive bearing clearance thicker oil will quiet it down

it's a troubleshooting method for what you're encountering

sending in some of the old oil is a great idea btw

About2Bite

ZZ06 I know how you feel...

...You guys were right on the lifters

About2Bite

What did you end up replacing?

Just lifters and cam? Bottom end was fine?

ZZ06

I know its hard to believe some random peeps on a forum. But the second I heard your clip, I knew. Yup, when I heard the problem in my ride, I limped the car home and didn't drive it again and only started it twice to for diagnostics. My bottom end was fine. I had custom cam speced, and went with LS7 lifters. Of course I believe its a "standard" replacement lifter now anyway. The springs that were from the first cam build were PRC EHT .675 springs. They were fine and hadn't lost much of anything for pressure. My mechanic inspected them as did I before I took it to him and they were fine for reuse. Just had the lifters replaced with the cam and rolled.. Out of curiosity, what oil were you using?

racebum

x2 on the oil

if you had solid oil pressure i'm surprised this happened if it was a half way decent oil like M1 high mileage or better

were you using some low pressure formula like standard mobil one or some off the shelf syn with a neutered zddp level?

i've roasted bearings before from oil starvation in high g corners but never have killed a cam