Lifters
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Its either piston slap or a connecting rod with excessive clarance. If you purchase a mechanics stephescope and put the rod on the valve cover (over top over each valve rocker),,, you can hear EACH ROCKER and its associated components. If its one of them, it will stand out like a sore thumb
If its a Con rod or piston slap, put the rod down near the oil pan (Between the pan and the spark plug) and the sound will be amplified the closer you get to it.
Before you go into pulling the heads,, give that simple test a go and see where you stand..
You can get four or five feet of 5/16 vacuum hose and do the samething. Put a small screw into one end and the other end in your ear. Place that screw end on (say a fuel injector) and listen to it to give you an idea how it works. Reve the engine and you can hear the firing frequency in the injector change..
If you just point the OPEN end of the hose at an area, it will guide you right to the noise area. You will be surprised at what you can hear with just a piece of vacuum hose.
Bill
If its a Con rod or piston slap, put the rod down near the oil pan (Between the pan and the spark plug) and the sound will be amplified the closer you get to it.
Before you go into pulling the heads,, give that simple test a go and see where you stand..
You can get four or five feet of 5/16 vacuum hose and do the samething. Put a small screw into one end and the other end in your ear. Place that screw end on (say a fuel injector) and listen to it to give you an idea how it works. Reve the engine and you can hear the firing frequency in the injector change..
If you just point the OPEN end of the hose at an area, it will guide you right to the noise area. You will be surprised at what you can hear with just a piece of vacuum hose.
Bill
Instructor
Joined: Feb 2014
Posts: 136
Likes: 6
From: Lees Summit Missouri
Its either piston slap or a connecting rod with excessive clarance. If you purchase a mechanics stephescope and put the rod on the valve cover (over top over each valve rocker),,, you can hear EACH ROCKER and its associated components. If its one of them, it will stand out like a sore thumb
If its a Con rod or piston slap, put the rod down near the oil pan (Between the pan and the spark plug) and the sound will be amplified the closer you get to it.
Before you go into pulling the heads,, give that simple test a go and see where you stand..
You can get four or five feet of 5/16 vacuum hose and do the samething. Put a small screw into one end and the other end in your ear. Place that screw end on (say a fuel injector) and listen to it to give you an idea how it works. Reve the engine and you can hear the firing frequency in the injector change..
If you just point the OPEN end of the hose at an area, it will guide you right to the noise area. You will be surprised at what you can hear with just a piece of vacuum hose.
Bill
If its a Con rod or piston slap, put the rod down near the oil pan (Between the pan and the spark plug) and the sound will be amplified the closer you get to it.
Before you go into pulling the heads,, give that simple test a go and see where you stand..
You can get four or five feet of 5/16 vacuum hose and do the samething. Put a small screw into one end and the other end in your ear. Place that screw end on (say a fuel injector) and listen to it to give you an idea how it works. Reve the engine and you can hear the firing frequency in the injector change..
If you just point the OPEN end of the hose at an area, it will guide you right to the noise area. You will be surprised at what you can hear with just a piece of vacuum hose.
Bill
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