Can anyone identify this knock?

J

JC316

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This is my 96 Mustang GT, but I have a 97 Lincoln Mark VIII LSC motor in it. It's driving me nuts. It's not in the oil pan or lower block, I checked with a stethoscope. I took the valve covers off and I found 13 bad lash adjusters and replaced with with used ones All of the lash adjusters were pumped up tight, so I ASSume that they are working fine.

Anyone encounter this before? Worst case, I will change out all of the lash adjusters with new ones, but before I throw cash at it I would like a second opinion.

YouTube- SDC14856.AVI
 
Definitely sounds like valve noise but to say what exactly I can't.
 
what weight oil are you using? try a thicker oil maybe it'll work...to me it sounds like lifters....check the lifter springs maybe you've got a broken one.
 
Yep, the heads are oiling properly. Using 5W30 oil. What is a lifter spring? All of the valve springs are in good shape.
 
when you put the camera under the car it seems to me that was the loudest, are you sure you have all the torque convertor nuts tight? sounds like one might be backed off and hitting the inside of the bell housing. i'd say its under the car, its much louder under the car than under the hood.
 
jamie97lsc said:
when you put the camera under the car it seems to me that was the loudest, are you sure you have all the torque convertor nuts tight? sounds like one might be backed off and hitting the inside of the bell housing. i'd say its under the car, its much louder under the car than under the hood.
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It's a 5 speed and yeah, the bolts that hold the flywheel on are fine.
 
JC,

If the engine sucked in a little water ( hydro-lock ) before you aquired it , it could be a bent rod hitting the block !

Good Luck,
Sonny
 
Justmy $.02

That sounds a lot like lifter tick... I've had some OHC cars that sounded EXACTLY like that when a lifter or 2 or several went bad..

On my Probe (yeah, I know..), one of the problems those cars have is the oil hole in the rocker arm gets plugged up and can't supply enough oil to the lifter. I've never had one of our engines apart, but how does the lifter get oil pressure?

Just an idea..
 
DUDE that is not a lifter tick, I am a mechanic, not a tick, that my friend is a knock, those engines do not, I mean do not have lifter problems, let alone 13 bad at one time, what makes a lifter(actually a lash adjuster) work is oil pressure, there is a spring inside them but still would work fine even if spring is bad. put a real pressure gauge on it and see what the oil pressure is, it should be close to 80 psi. You probably have a spun rod bearing causing really low oil pressure.
 
jamie97lsc said:
did you hear the motor run before you put it in the mustang?
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No, I got it out of a pick U pull. The car was wrecked, so I know it was running. This has been like this since last year, it hasn't gotten better or worse.
Sonny Day Out said:
JC,

If the engine sucked in a little water ( hydro-lock ) before you aquired it , it could be a bent rod hitting the block !

Good Luck,
Sonny
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I doubt that very seriously, these rods don't bend, they disintegrate since they are pressed rods. On top of that, there is 0 knocking in the oil pan and the block. That was the first thing that I checked.

dcrews said:
Justmy $.02

That sounds a lot like lifter tick... I've had some OHC cars that sounded EXACTLY like that when a lifter or 2 or several went bad..

On my Probe (yeah, I know..), one of the problems those cars have is the oil hole in the rocker arm gets plugged up and can't supply enough oil to the lifter. I've never had one of our engines apart, but how does the lifter get oil pressure?

Just an idea..
Click to expand...

They sit down in a hole in the head and the oil comes from there. I am thinking that it's the lifters too since I hear the knocking best right on top of the intake.

jt351 said:
DUDE that is not a lifter tick, I am a mechanic, not a tick, that my friend is a knock, those engines do not, I mean do not have lifter problems, let alone 13 bad at one time, what makes a lifter(actually a lash adjuster) work is oil pressure, there is a spring inside them but still would work fine even if spring is bad. put a real pressure gauge on it and see what the oil pressure is, it should be close to 80 psi. You probably have a spun rod bearing causing really low oil pressure.
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I am a mechanic too, I really know my stuff and I know what a spun rod bearing sounds like. This is no rod bearing, I have put over 15K miles on this engine without it getting any worse. I took the pan off when I swapped it in and there were no spun bearings. Disabling the cylinders one at a time doesn't do anything to it.

The old 2V that was in this car had the exact same knocking, I rebuilt that engine top to bottom, minus the lash adjusters and it still knocked. Autopsy of it showed 6 bad lash adjusters, the springs inside were completely stuck down, as in no resistance at all.
 
Well I bought a 97 mustang gt with a bad waterpump and did not run, It cranked with zero compression, I had nothing to lose so I pulled the heads, the pistons looooked fine but heads warped so bad it blew the mls gaskets, I threw a set of PI heads on it runs great but has a very loud tick for 10 minutes until engine is warmed up, I figure it is a cracked piston skirt. And I also know for a fact that those rods can bend, I had a customer with a 98 crown vic that drove threw 3 feet of water, it had a knock for 3 months when the insurance company finally decided to pay to fix it it, it had shorted and bent one rod so much the crank throw was hitting the piston. I know rare but happened, and it was a stock cintered sht metal rod. so what is your oil pressure?
 
jt351 said:
Well I bought a 97 mustang gt with a bad waterpump and did not run, It cranked with zero compression, I had nothing to lose so I pulled the heads, the pistons looooked fine but heads warped so bad it blew the mls gaskets, I threw a set of PI heads on it runs great but has a very loud tick for 10 minutes until engine is warmed up, I figure it is a cracked piston skirt. And I also know for a fact that those rods can bend, I had a customer with a 98 crown vic that drove threw 3 feet of water, it had a knock for 3 months when the insurance company finally decided to pay to fix it it, it had shorted and bent one rod so much the crank throw was hitting the piston. I know rare but happened, and it was a stock cintered sht metal rod. so what is your oil pressure?
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That 10 minute knock is likely piston slap. Pretty well documented on the 2V engines. Yeah that is rare for it to bend, every one that I have seen just crumbles. My oil pressure hovers around 60PSI. Like I said, I pulled the pan and checked the rods, everything was fine.

I can tell you what it's not. It's not a rod, it's not the timing chain, it's not the flywheel, it's not an exhaust leak or a broken catalytic converter and it's not a spark plug getting ready to blow. That leaves me with cracked piston, which is unlikely since it doesn't smoke and the compression was fine. Wrist pin, which I have never seen an actual documented case on a 4.6L engine. Lifters or something else in the valve train.
 
When you pulled the pan did you actually check all the rod bearings by pulling the caps off? I bought my 2000 lightning not knowing anyhing was wrong with it, sounded quiet when I test drove it, but it had a little dry rattle at cold start that I didn't like, It was quiet even if I hammered on it. I pulled the pan on it and found #1 rod bearing had complety spun taking a 1/8" of the crank with it. so I said fuuuuuuuudddddggge, and had to pull engine, I rebuilt it with new crank and h-beams. Not sure the oiling sytem in a dohc, but could a main mearing have spun and stopped oil flow to head causing collapsed lifters, all while maintaining good oil pressure.
 
When you pulled the pan did you actually check all the rod bearings by pulling the caps off? I bought my 2000 lightning not knowing anyhing was wrong with it, sounded quiet when I test drove it, but it had a little dry rattle at cold start that I didn't like, It was quiet even if I hammered on it. I pulled the pan on it and found #1 rod bearing had complety spun taking a 1/8" of the crank with it. so I said fuuuuuuuudddddggge, and had to pull engine, I rebuilt it with new crank and h-beams. Not sure the oiling sytem in a dohc, but could a main mearing have spun and stopped oil flow to head causing collapsed lifters, all while maintaining good oil pressure.
 
Lol, I must be a complete idiot! Because when you say "disabling the cylinders 1 at a time doesn't do anything to it", I laugh my ass off!!! Is that cylinder not still holding moving mechanisms?? Lol. I'm such an ass. In all seriousness, I don't see what any knocking difference would be whether it's under load or not.
 
Disabling spark or fuel is a trick mechanics use all the time. Here's my try, since most everything else has already been suggested, how about the Secondary chain tensioner?
 
There is a screened port on each head for the oil feed. On the passenger side it is to the rear and on the drivers side it is towards the front.

Lubrication System

1. Oil is drawn into the oil pump through the strainer in the sump.

2. Oil is pumped through the filter assembly on the left front side of the block.

3. Oil enters the main oil gallery where it is distributed to the crankshaft main journals, and to both cylinder heads.

4. From the main journals the oil routed through cross drilled passages in the crankshaft to the crankpins for rod bearing lubrication. Controlled leakage through the main and connecting rod bearings is slung radially outward to cool and lubricate the cylinder walls as well as the entire connecting rod, piston and ring assemblies.

5. The left cylinder head is fed from a drilling into the lateral supply passage feeding the main gallery at the front of the block. The right cylinder head is fed from a drilling into the rear of the main gallery. Main gallery pressure is reduced as it enters the head galleries through the use of fixed serviceable orifices located at the upper part of the feed passages. It is this reduced pressure in the cylinder head galleries which feeds the camshaft journals, the valve lash adjusters and the chain drive hydraulic tensioners.

6. The cam lobe and roller followers are lubricated by splash created through valve train operation.
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I would look into that if it were mine.
 
Lifters DO go bad in these cars and make a horrendeous sound.
Without having the car here to look at is a tough call from a video but thats my guess.

Is it all the time? Knock sensonrs aren't throwing a ce?
 
sounds exactly like my 150 when i slipped the clutch to hard 1 time. From the sound in the video id say its clutch, pressure plate related. I would pull it apart and look for witness marks, or the simple fix, burn the clutch and see if the noise changes. If you can make the clutch slip your gonna need a new one later on anyways or somethings not right in their.

i can gaurentee after watching this 3 times its in the clutch setup.

Only reason i know this is because i moved a jet heater at work in deep snow, made my clutch slip. This is the exact noise i had after it slipped. I did the easy fix, put it in 4x4 took it out on the road and smoked first and second. Noise went away after that.
 
i tend to agree w/ ground zero.

sounds like a whacked pilot bushing/input shaft

especially since the prior 2v made the same sound according to the original poster.

my svo made that noise...many times



but i aint no mechanic er nuthin
 
jt351 said:
When you pulled the pan did you actually check all the rod bearings by pulling the caps off? I bought my 2000 lightning not knowing anyhing was wrong with it, sounded quiet when I test drove it, but it had a little dry rattle at cold start that I didn't like, It was quiet even if I hammered on it. I pulled the pan on it and found #1 rod bearing had complety spun taking a 1/8" of the crank with it. so I said fuuuuuuuudddddggge, and had to pull engine, I rebuilt it with new crank and h-beams. Not sure the oiling sytem in a dohc, but could a main mearing have spun and stopped oil flow to head causing collapsed lifters, all while maintaining good oil pressure.
Click to expand...

Nope, I didn't pull the caps since I would have had to changed out the bolts, damn stretch bolts are expensive.

poniesviii said:
Lol, I must be a complete idiot! Because when you say "disabling the cylinders 1 at a time doesn't do anything to it", I laugh my ass off!!! Is that cylinder not still holding moving mechanisms?? Lol. I'm such an ass. In all seriousness, I don't see what any knocking difference would be whether it's under load or not.
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It's just a trick that can help find it. If the cylinder isn't firing, then there is less pressure and thus less knocking on the cylinder. Got a 2000 Chevy Metro sitting in my garage right now that had a spun rod bearing, disabling that cylinder drastically stopped the sound.

driller said:
There is a screened port on each head for the oil feed. On the passenger side it is to the rear and on the drivers side it is towards the front.

I would look into that if it were mine.
Click to expand...
Checked that already. Good try though, I thought the same thing.

ONEBADMK8 said:
Lifters DO go bad in these cars and make a horrendeous sound.
Without having the car here to look at is a tough call from a video but thats my guess.

Is it all the time? Knock sensonrs aren't throwing a ce?
Click to expand...
No knock sensors. I reused my GT harness and the GT's don't have them.

ground_zero298 said:
sounds exactly like my 150 when i slipped the clutch to hard 1 time. From the sound in the video id say its clutch, pressure plate related. I would pull it apart and look for witness marks, or the simple fix, burn the clutch and see if the noise changes. If you can make the clutch slip your gonna need a new one later on anyways or somethings not right in their.

i can gaurentee after watching this 3 times its in the clutch setup.

Only reason i know this is because i moved a jet heater at work in deep snow, made my clutch slip. This is the exact noise i had after it slipped. I did the easy fix, put it in 4x4 took it out on the road and smoked first and second. Noise went away after that.
Click to expand...

I thought about that too, but it doesn't make a difference if the clutch is in or out. When I was in there, I put a new pilot bearing it, a new throw out bearing and a new clutch. However, in my haste, I never resurfaced the flywheel. Couldn't believe I made such a rookie mistake when I got it all back together. Did you truck make this noise even with the clutch depressed?
 
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