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Old 05-28-2014, 08:02 PM   #1
Old Glory
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Engine noise diagnosis

http://youtu.be/ZPW-w7D2u4I

Engine experts, what do you think? Bad rocker,lifter, worse?
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Old 05-28-2014, 08:08 PM   #2
msgdsrf
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Re: Engine noise diagnosis

My two cents, exhaust leak around your manifold or the manifold itself.
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Old 05-28-2014, 08:10 PM   #3
Old Glory
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Re: Engine noise diagnosis

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Originally Posted by msgdsrf View Post
My two cents, exhaust leak around your manifold or the manifold itself.
It definitely has an exhaust leak, but it just started making the loud clanking sound. It had been sitting up for 15 years and I fired it up recently. It idled fine for a while before the clanking noise started.
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Old 05-28-2014, 08:19 PM   #4
Hawghauler
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Re: Engine noise diagnosis

It's really hard to judge with just a recording. Some background would help.
Did it just start doing this?
Is this a truck that's new to you?
How long since it ran last?
Any extra information you can think of that might be relevant.

If it's a light knock, and it's been sitting or hasn't had the oil changed in a long time, it could be sticking or plugged lifters. Add a half a quart of trans fluid to the oil and run it for a while and it may ease off.

If it's a loud deep knock, it's probably time for a tear down, or replacement.

Using a long rod, like allthread or a tire iron. Put your thumb over one end to protect your ear, then use this as a stethoscope and trace the position of the knock. First touch one end of the rod to the top of the valve cover, and the other up to your ear. Slide down the length of the valve cover listening for the loudest knock. If they all seem the same, you can do this with the side of the block as well.
Watch out for that fan blade and those spinning belts!
Generally if you don't find it in the valve cover, it's major, and time for a pretty serious tear down.
Good Luck.
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Old 05-28-2014, 08:37 PM   #5
Old Glory
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Re: Engine noise diagnosis

Quote:
Originally Posted by Hawghauler View Post
It's really hard to judge with just a recording. Some background would help.
Did it just start doing this?
Is this a truck that's new to you?
How long since it ran last?
Any extra information you can think of that might be relevant.

If it's a light knock, and it's been sitting or hasn't had the oil changed in a long time, it could be sticking or plugged lifters. Add a half a quart of trans fluid to the oil and run it for a while and it may ease off.

If it's a loud deep knock, it's probably time for a tear down, or replacement.

Using a long rod, like allthread or a tire iron. Put your thumb over one end to protect your ear, then use this as a stethoscope and trace the position of the knock. First touch one end of the rod to the top of the valve cover, and the other up to your ear. Slide down the length of the valve cover listening for the loudest knock. If they all seem the same, you can do this with the side of the block as well.
Watch out for that fan blade and those spinning belts!
Generally if you don't find it in the valve cover, it's major, and time for a pretty serious tear down.
Good Luck.
Thanks for the info. It had been sitting up for 15 years, but the engine was fine the last time it ran. For the first hour or so after cranking it, it didn't make any clanking noise and idled fine. After shutting it off and restarting a few hours later the clanking noise began. I had changed the oil before restarting.
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Old 05-28-2014, 08:58 PM   #6
hamjet
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Re: Engine noise diagnosis

sounds to me, (for what its worth) like a lifter's not pumping up, could be sludge, dirt, or some crud made its way to the lifter. I would try to isolate it by use of a stethascope, ( a big screw driver works) along the valve cover, intake man. to narrow it down. I'd pull the valve cover and put said stethascope on the rocker stud too. once you're sure which lifter it is, try tightening it a 1/4 to 1/2 turn on the rocker nut to see if it stops.2 cents.....
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Last edited by hamjet; 05-29-2014 at 04:32 PM.
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