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Old 05-17-2021, 10:43 AM
supersport#69 supersport#69 is offline
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Default Engine noise question

I can’t tell if my engine is making a noise inside or some other outside noise causing it.
When I first start it it’s quiet. After a few minutes of warming up I hear a faint sound but I can’t pinpoint what it is. I
I took it to my mechanic and he can hear it but also can’t figure it out. He listened through stereoscope and can’t identify it.
There’s good oil pressure, the noise doesn’t get louder when you rev it, you have to put your ear close to even hear it, He said it’s not knocking or something major in his opinion.

What are some things I should look out or listen for to make sure it is nothing big?

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Old 05-17-2021, 11:11 AM
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"Making a noise"... "Faint sound"...That's pretty vague. A little more info is in order. Tapping? Clicking? Whining? Squeaking? See what I mean?

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Old 05-17-2021, 11:51 AM
supersport#69 supersport#69 is offline
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I guess that was pretty vague.

It sounds a bit like a ball lightly swirling around in a tin can? Again, it’s faint. I don’t hear anything that sounds like a knock, ticking, or exhaust leak sounding.

He said possibly a “sticky” lifter but can’t be sure and sounded unlike exhaust or tapping to me.

Is there anything externally like maybe that the stove over drivers side exhaust manifold that could make that sound?

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Old 05-17-2021, 11:57 AM
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Swirling around in a tin can makes me think of alternator bearing, power steering bearing etc. If it doesn't get louder when you increase rpm, does it get faster?

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Old 05-17-2021, 12:29 PM
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Can you associate the cadence or frequency of the sound to the speed of the crank, cam or an engine accessory? Crank speed could be cracking or loosening flex plate, for example. Half crank (cam) speed could be valve train, fuel pump, distributor etc.

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Old 05-17-2021, 01:10 PM
supersport#69 supersport#69 is offline
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There doesn’t seem to be any association with Revving it up. The mechanic was leaned in over the fender and lightly controlling the throttle up and down listening and couldn’t hear a difference. Just a faint consistent sound that starts after it’s warmed up.
I don’t even hear it until it’s been running a few minutes and nearing the 180 mark.
I don’t really hear the noise in the front of the engine. It sounds like it’s somewhere in the back half but I can hear it the same on both sides of the engine. He says he doesn’t think it’s much to worry about but I’d rather not blow it off if possible.

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Old 05-17-2021, 01:17 PM
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Could be many things. I just had a balancer fail...on it's way out it made some odd noises that were difficult to pinpoint. You can eliminate a lot by removing belts one by one.

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Old 05-17-2021, 01:28 PM
supersport#69 supersport#69 is offline
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It might just be coincidence but recently I changed oil and I didn’t fill the new filter up with oil. Would that matter?
I did 5 quarts of vr1 10/30 and Wix filter. I lubed filter too but didn’t pour oil in it.

I didn’t hear any weird noise at start up, and ran fine. I’m reaching hear but trying to see if I screwed up.


Last edited by supersport#69; 05-17-2021 at 01:50 PM.
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Old 05-17-2021, 02:22 PM
supersport#69 supersport#69 is offline
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Ok as it’s worrying me now I called my mechanic to make sure I’m clear in details.

So as for cadence he did say the sound sped up with revving the engine but didn’t get louder, just faster.

I don’t have a flex plate, the distributor wasn’t moving when he checked it, the fuel pump/power steering/alternator being in front-noise in lower rear of engine.

He said it’s a small tick and he thinks it’s a sticky lifter because the sound wasn’t on just one side and not in top end.
He doesn’t believe it’s rod bearing, or anything in bottom end.

His advice is drive it. He also didn’t think me not priming filter was anything horrible.

My gut says he’s right that a lifter is making noise. Any chance that goes away or do they just get worse?

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Old 05-17-2021, 03:22 PM
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throw out bearing assuming manual trans

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  #11  
Old 05-17-2021, 04:16 PM
supersport#69 supersport#69 is offline
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It is the original Muncie 4 spd it came with-not rebuilt. I want to say he replaced that part though when it was unbolted but of course nothing is made well, so who knows.

Can a bad one make a faint tick sound? Will it start after warmed up? Will clutch movement be effected at all in shifting or height of the pedal?

Thinking about this, I'm not sure if the sound was ever checked while in gear.


Last edited by supersport#69; 05-17-2021 at 04:52 PM.
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Old 05-17-2021, 09:59 PM
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Could it be possible that you have a slight exhaust leak. When the gasket between the head and exhaust manifold gets a slight leak it sounds like what your describing.

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Old 05-17-2021, 11:39 PM
supersport#69 supersport#69 is offline
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I was thinking that was a possibility but it is not clear which side it’s coming from.

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Old 05-18-2021, 07:58 AM
ddcrank ddcrank is offline
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A slight exhaust leak is like a mouse in the wall. You never really know where it is until you put your ear against the wall and hunt it down.

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Old 05-18-2021, 09:42 AM
supersport#69 supersport#69 is offline
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If an exhaust leak would it make noise from the start or after warmed up? I don’t hear anything for the first couple of minutes.

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Old 05-18-2021, 09:51 AM
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Yep, parts expand with heat. Some cold leaks will close and become silent, some open gaps as expansion occurs.

Ince the noise is there, you can squirt some oil down the carb to create smoke, then watch for smoke around the manifolds.

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