Help w/ Noise Diagnosis FZJ80 engine

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Jan 17, 2018
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Aliso Viejo, CA
Hey all,

I am thinking of picking up a 96 lx450 w/ 101k miles. My only concern is the noise coming from engine. Clueless what it may be.
My other 96 lx450 has 249k miles and MUCH quiteter than this guy.
Does anyone recognize this noise and maybe direct me with what it may be?

Here is the link:



Any help is appreciated. Thanks everyone!
 

baldilocks

Battle Ground, WA
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Before jumping off into an engine rebuild, look for an exhaust leak. It sounds squeaky. Start at the small hose that ducts exhaust gasses up to the egr modulator.
 
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Aliso Viejo, CA
Before jumping off into an engine rebuild, look for an exhaust leak. It sounds squeaky. Start at the small hose that ducts exhaust gasses up to the egr modulator.
Perfect. I will check on that and report back. I'm clueless when it comes to sounds, partly because my hearing sucks!
 
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Across the pond, and upside down
Sounds nasty. It does sound like there could be an exhaust leak. But also sounds like a heavy mechanical knock.

Grab yourself a 2' long extension bar or 2' long screw driver.
Hold one end against different parts of the running engine, wrap your fist around the other end, rest your ear against your fist.
This amplifies the sound and helps pinpoint where its coming from.
You'll be able to hear if it's in the top end, or the bottom end. At the front or rear.

Obviously, keep clear of fan belts etc
 
Joined
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Messages
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Sounds nasty. It does sound like there could be an exhaust leak. But also sounds like a heavy mechanical knock.

Grab yourself a 2' long extension bar or 2' long screw driver.
Hold one end against different parts of the running engine, wrap your fist around the other end, rest your ear against your fist.
This amplifies the sound and helps pinpoint where its coming from.
You'll be able to hear if it's in the top end, or the bottom end. At the front or rear.

Obviously, keep clear of fan belts etc
Heard about this being done, never tried it. Guess there's only one way to find out if it works! Going to give the redneck stethoscope a crack at it.
 
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One thing I was told is there was a Lucas oil stabilizer used in last oil change as vehicle can sit for month at a time at the Utah vacation property. Not sure if that can anything to do with it.
 
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Heard about this being done, never tried it. Guess there's only one way to find out if it works! Going to give the redneck stethoscope a crack at it.

It absolutely works. Take some time to listen to different parts, all over. You'll get a sense of what sounds typical, and what just ain't right.

Its helped me diagnose stuff with impressive accuracy a few times.
 
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Craig, CO
Does it go away after a few/several minutes after the truck warms up? In other words do you only hear it during a cold startup. I'm chasing a similar sound (for 2 years now) fixed an exhaust leak and couple other things, sound still there. Looked in each cylinder and decided #3 must have some piston slap. The knock mostly disappears after the piston and block warm and expand. Others said a loose sparkplug can produce a noise like that, might want to check them.

I'm interested in what you find.
 
Joined
Jan 17, 2018
Messages
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Aliso Viejo, CA
Does it go away after a few/several minutes after the truck warms up? In other words do you only hear it during a cold startup. I'm chasing a similar sound (for 2 years now) fixed an exhaust leak and couple other things, sound still there. Looked in each cylinder and decided #3 must have some piston slap. The knock mostly disappears after the piston and block warm and expand. Others said a loose sparkplug can produce a noise like that, might want to check them.

I'm interested in what you find.
Interesting. I will check spark plugs as well.
 

SmokingRocks

I bought a Cruiser to keep miles off my Cruiser
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I'd poke around the engine bay to see if something has come unbolted or is loose, sounds like it could be something rattling at idle. I've identified things like this before by turning the engine off then literally beating around the engine bay, on the engine, fenders etc like the truck owes me money, sometimes doing this will replicate the vibration and recreate the rattle.
 
Joined
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Messages
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I'd poke around the engine bay to see if something has come unbolted or is loose, sounds like it could be something rattling at idle. I've identified things like this before by turning the engine off then literally beating around the engine bay, on the engine, fenders etc like the truck owes me money, sometimes doing this will replicate the vibration and recreate the rattle.
Ha this son bitch does owe me money so I will try and keep the beating to a minimum. Thanks for the tip!
 
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What oil filter is currently installed? We’ve had problems with Wix/Napa Gold filters.
Looks like a NAPA pro select.

20211014_132157.jpg
 

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