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Discussion Starter #1
Hi all, new member here. Just bought my uncles 74 Nova Custom with a 250 inline. He hasn’t driven it in about 10 years, but right before he parked it, he noticed the engine was making a dry squeaking sound at idle. He had no idea what it was, so he parked it. It only happens when the engine warms up, it sounds like it’s coming from the front of an engine. Took all the belts off and it was still there. Doesn’t sound like a rod knock or lifter clatter. Any thoughts?
Here’s a link to it, hope it works: IMG_6372.MOV
 

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Discussion Starter #3
Never heard of that happening, is that an easy check? Would it only happen when the engine warms up?
 

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1970 Nova SS 350 Brandon, MS
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Or it could be the timing tab rubbing the balancer. Mine was doing that and I almost went crazy trying to figure it out.
 

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Does it have a clutch fan on it?

Miles
 

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It could???? be the cam gear rubbing the timing cover??? But normally other noises come along with that. Could also be the crank shaft seal.
 

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Discussion Starter #8
Sorry for late reply, but yes had oil pressure gauge, and it sits right around 30psi at idle. Has clutch fan, but took all the belts off and the sound is still there
 

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I'm thinking a video would help this quite a bit.

Miles
 

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The OP provided a video in his 1st post. IMG 6372.MOV.
I watched/listened but my hearing is so bad now I couldn't hear the squeak (high freq.).
 

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Hi all, new member here. Just bought my uncles 74 Nova Custom with a 250 inline. He hasn’t driven it in about 10 years, but right before he parked it, he noticed the engine was making a dry squeaking sound at idle. He had no idea what it was, so he parked it. It only happens when the engine warms up, it sounds like it’s coming from the front of an engine. Took all the belts off and it was still there. Doesn’t sound like a rod knock or lifter clatter. Any thoughts?
Here’s a link to it, hope it works: IMG_6372.MOV
Pull the Valve cover---look for a dry rocker arm pivot ball----they produce a very high pitch noise when dry---may be a damaged pushrod on either end----lifter can't pass oil up through the pushrod---start lookin'---good luck
 

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Okay, my bad...I was listening for a squeak but that's not what we're listening for, is it? 🥴 DOH!
 

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Discussion Starter #14
I guess it isn’t necessarily a squeak. It’s really hard to describe. Almost sounds like the timing gear running or something. Wouldn’t be speedo cause it’s there when it’s parked and idling.
 

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Ok how about distributor rotor, alternator bearing ,water pump bearing, power steering pump low on fluid a/c compressor bearing?
 

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Discussion Starter #16
I can confirm it’s none of the accessories. We had the belts off and ran the engine and it’s still there. My best guess is the timing gear is rubbing, or a bad cam bearing.
 

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Sounds almost like a mechanical knock. Does the noise change when you lightly rev the motor, if so , that would indicate a piston/bearing issue. If the car has been sitting, a hydraulic lifter could be sticking, that would give a lite ticking noise. Otherwise, I would change the oil and filter, and just drive it a little. Likely it will quiet down, or if there is a real issue, get worse and easier to locate.
 
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