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Old Dec 9, 2020 | 11:37 AM
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Default Engine Noise
This is a SBC rebuild. The cam has been broke in and has about 90 minutes of total run time. There seems to be a "rattle" coming from the front of the engine.
Only sources can be fan clutch, water pump, or alternator? I know the fan clutch is bad and will be replaced. The water pump is not leaking.
What do you hear?

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https://streamable.com/6fkwit

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Old Dec 9, 2020 | 11:50 AM
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IMHO...
1. Fan belt slippage noise from loose belt and pulleys.
2. timing chain slap.

Unkahal
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Old Dec 9, 2020 | 11:51 AM
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I have found that a stethiscope from harbor fright to be an invaluable tool. You can dial in noises easily.
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Old Dec 9, 2020 | 12:02 PM
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Did you try running it for a few seconds with the belt off to see if the noise stops?
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Old Dec 9, 2020 | 12:03 PM
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sounds like alternator bearing or clutch fan
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Old Dec 9, 2020 | 01:13 PM
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Originally Posted by VF-301
I have found that a stethiscope from harbor fright to be an invaluable tool. You can dial in noises easily.

I agree! https://smile.amazon.com/Lisle-52750...s%2C235&sr=8-5
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Old Dec 9, 2020 | 01:23 PM
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A rattle or a "clicking" sound? Couldn't tell from the video. A clicking sound can be caused by a leaky header or exhaust manifold gasket.

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Old Dec 9, 2020 | 09:51 PM
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Originally Posted by L-46man
IMHO...
1. Fan belt slippage noise from loose belt and pulleys.
2. timing chain slap.

Unkahal
The timing chain is new and tight. Could there still be chain slap?
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Old Dec 10, 2020 | 09:54 PM
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Get a stethoscope as suggested. Listen to stuff on that left side. Rocker arms, alternator. You can sometimes use a piece of hose to listen as well.

A new timing chain should not slap but sometimes things don't fit like they should. I think it would have been apparent with assembly. Intermittent rocker arm noice is possible. But, you really need a stethoscope.
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Old Dec 11, 2020 | 09:05 PM
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Originally Posted by 71 Green 454
Did you try running it for a few seconds with the belt off to see if the noise stops?
I removed the belt today. It is much quieter. With the belt off, I can slightly wobble/rock the fan clutch and wp pulley. I'm guessing the wp bearing are shot eventhough the wp is not leaking. I can give the fan a "spin" and it makes a rattle/rumble sound.



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