RockinWs6

Very simple way to test for lifter noise is by putting 8-10 ozs of ATF in the engine oil. Mine was a lot louder than yours and it was all lifter noise. Also if you pull the valve covers you will find a loose rocker. I listened to mine rap like this for 80k...not nomo, its quiet as a mouse.

Steve91T

Really? What does the ATF do? Free up a stuck lifter? Are you saying the dump ATF in and run it for a bit to see if it changes the sound of that the ATF will actually fix the lifter. I'm assuming you mean to use ATF as a diagnostic tool.

I'm afraid the cam might be damaged from the bad lifter (if that's what it is).

ss454327

iTrader: (10)

My neighbor bought a procharged Vette with the same sound. Ran fine just knocked. He thought it was just a lifter and bought it anyway. Turned out to be a broken piston and cracked block between the cylinders.

Steve91T

Wow no kidding. And it still ran? How's that possible? Anything is possible, but I'd be surprised if that's the case with this engine. It's bome stock and hasn't been run very hard. But you never know.

I think the plan is to drain the oil into a clear container and look for metal. Then pull the valve covers and go from there.

ss454327

iTrader: (10)

Yeah it drove fine and had tons of power. The piston fell into two pieces when he pulled it out of the block. He showed it to me and I couldn't believe it was even running. Didn't have any scarring or anything just a big crack all the way through the piston. He bought an LQ9 long block and swapped it in with no issues.

wildcamaro

iTrader: (15)

That's a lot of miles, it honestly sounds like a knock from the video...autozone now rents a borescope so you can look down into engine to help you with diagnosing the issue

Steve91T

I just got off the phone with the original owner. He told me it started after getting off the highway. Just cruising in 6th. When he came to a stop, he heard the knocking. That was back in January. He has changed the oil 4 times since then, trying differently weight oils. No metal was every found in the oil. 2 months ago, he changed the rockers and pushrods.

So, it's not the bottom end. The car has driven nearly every day for 6 months with this knock and it's not making metal. If it was in the bottom end, there's no way it'd still be running. It's probably a failed lifter.

Steve91T

Found it!

Steve91T

The bolt holding the rocker was tight and the pushrod isn't bent so the lifter is probably bad. The head is coming off.

Steve91T

Intake manifold is off.

Steve91T

Look what I did today!!! Looks like the cam is coming out. #6 lifter spins freely, moves up and down from the cam to the "spot". That'd where it gets stuck. It will absolutely not come out. It's probably mushroomed. #7 looks bad also. Really pitted. So the cam has to come out. The good news is the lifter will probably drop down once the cam is out and then I can get it out that way. Hopefully the bore isn't messed up.








One of the good lifters


#7

Steve91T

Any thoughts will be appreciated. What do you guys think about the condition of the Pistons and the valves? Should I attempt to clean them?

RockinWs6

When the plunger in the lifter gets stuck it sure beats the hell out of the roller. Unfortunately dirt is the culprit 99% of the time so sometimes replacing the lifters helps at 1st but the trouble may return. After replacing the worn parts I would run Diesel grade oil like Delo 400 XLE with a small amount of ATF added to be sure the engine gets cleaned up. I've had lifter troubles with ALL 6 LS1 cars I've owned, since I switched to diesel oil and ATF I've had no more troubles. I think the piston design in these engines along with the poor crankcase ventilation system lets a lot of crap form in oil and the lifters can't handle it.

RockinWs6

I would clean up the gasket surfaces and let the rest be, it will look like that is a few miles anyway and cleaning around piston risks dropping crap down along rings<not good

Jimbo1367

Hopefully none of the debris (lifter & cam) went through the engine. Best of luck.

Steve91T

Hey guys! Thought I'd update this post in case it can help anyone in the future. Turns out the roller bearing on the lifter siezed and was grinding away on the cam. Eventually it ground all the way up the lifter until the whole thing came apart. When I pulled the cam, that's when the lifter came out the bottom. I found the rest of the lifter, needle bearings and all kinds of trash in the oil pan. The cam bearings were trashed so I went to Hawks and picked up a 150k mile short block for $700. I also had the heads cleaned up and rebuilt with new springs and seals. I installed a Texas Speed mild cam and swapped everything over. Life got in the way, as it normally does, so this project took longer than expected. Just last night I fired it up for the first time! It sounds great, no leaks and makes great oil pressure. My tach isn't working, so I'll have to check the cam position sensor. Here are all the pics with a short video at the end.









New used block



Hard to believe it's got 150k miles on it.











Fixing the old engine.

Steve91T

So today I pulled the manifold and found one problem, but created another. I never plugged in the cam position sensor, so that was an easy fix. But in the process, I broke the oil pressure wire. So I had to take the connector apart to get enough wire to solder, but so far it seems to be working.

Pretty easy fix though! Tach is working, engine starts easier and oil pressure gauge still works.

Tuning to come! I'm anxious to see what kind of numbers it makes with a small cam and the stock manifolds and cats.

LQ4-E39

iTrader: (7)

Nice job, that cam was wrecked!