Something doesn't sound right!

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doogievlg

doogievlg

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Noticed a strange noise coming from my engine yesterday and it's got me stressed out. Typically the exhaust leak is bad but I have never heard almost knocking noise this thing is making. Should I be concerned?

 
Things always sound different through speakers rather than in person, but I'd be pulling that valve cover for a look.
You always hear checking the converter bolts, but they usually make noise with a cold engine and it changes as the engine warms up.
Couldn't hurt to check them obviously, but that sounds like rocker gear noise to me.
 
TrailBeast said:
Things always sound different through speakers rather than in person, but I'd be pulling that valve cover for a look.
You always hear checking the converter bolts, but they usually make noise with a cold engine and it changes as the engine warms up.
Couldn't hurt to check them obviously, but that sounds like rocker gear noise to me.
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The car was not making that noise when I started it. That was after a short drive and idling in the garage for a few minutes. The engine was well warmed up. The heads are about 3 years old but I am still using the factory rockers on aluminum heads.
 
I hear two different sounds, one is a mild thumping like a header leak and the other is a sound that rockers make when they need adjustment. But what Trailbeast said is also true "sounds different if you're there". Have you put the handle of a long screwdriver to your ear and touch the other end to the rocker cover?? Then move to different spots on the cover and see what you hear.


Treblig
 
Treblig said:
I hear two different sounds, one is a mild thumping like a header leak and the other is a sound that rockers make when they need adjustment. But what Trailbeast said is also true "sounds different if you're there". Have you put the handle of a long screwdriver to your ear and touch the other end to the rocker cover?? Then move to different spots on the cover and see what you hear.


Treblig
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I actually have a long pipe i use for that but I could not find it yesterday. I just was freaking myself out that it was more of a knock in the rotating assembly.
 
If you are using hydraulic lifters that thing is noisey.

If you are using solids, tighten up the lash. Sounds like a thrashing machine.
 
doogievlg said:
I actually have a long pipe i use for that but I could not find it yesterday. I just was freaking myself out that it was more of a knock in the rotating assembly.
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Before you go jumping to the rotating assembly route I would first make absolutely sure you don't have a header leak. I've heard header leaks that make many different sounds, some of them really fool you. The simplest solution is usually the answer.

Treblig
 
Doesn't sound like lower end to me. But it's not "just" and exhaust leak there. I'd pull the valve covers and intake and take a look at the cam and lifter preload.
 
If your using stock rockers with high pressure springs make sure that one of the pushrods didn't push through the rocker arm.
 
No it wouldn't be a waste, that's what I did because of the very scenario I mentioned above. It happened once, replaced the rocker, happened a second time and I actually went to a complete roller valve train.
 
I know it's a long shot maybe, I'd pull the accessory drive belt off just to make sure there's not a water pump etc knocking around. Just takes a little time.
 
Dubob said:
I know it's a long shot maybe, I'd pull the accessory drive belt off just to make sure there's not a water pump etc knocking around. Just takes a little time.
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It's possible.
I have heard belt noises that sounded like a light rod knock.
 
If i was to take everything off the front of the engine and turn the water pump by hand I should be able to feel the knock correct?
 
doogievlg said:
If i was to take everything off the front of the engine and turn the water pump by hand I should be able to feel the knock correct?
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I've never heard a WP knock.

I hear lotsa noises;
All those already mentioned,and
I really think I might be hearing a rod in there.
Slow the engine down to 700 or less if it will go there. Then saw on the throttle arm ever so slightly. If it's a rod, then every time the rod is unloaded, it will hammer. So, the sound will not be there when you open the throttle, but the millisecond you are backing off the throttle;knock-knock, there it will be. And then it will be gone. That is how they (rod-knocks) have always started for me.
This stage does not usually last long.:(
 
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Drain your oil. It cost nothing if you use a clean pan. If you see anything other than oil you really need to cut the filter. If you see nothing in the oil you should cut the filter anyway and if all of the above appears to be in order knock off a valvecover. Clean oil typically means whatever noise you have is not heading you down the road of disaster in my experience but based on your video you have something ping, pang, pong going on.... Hopefully it is something eazy peazy to resolve.....

JW
 
doogievlg said:
Hydraulic lifters. I'll pull the valve covers this weekend.
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No way I could wait that long!
Heard a noise, got my cheap parts store stethoscope, located it and pulled the valve cover in about ten minutes. This is what I found. Borrowed an adjuster and had it back on the road, no problems for many, many miles since.
Why sit around wondering what it might be, asking other people and torturing yourself? Take 20 minutes and go pull the covers. You'll feel better just knowing.

20170309_143954.jpg
 
KnuckleDuster said:
No way I could wait that long!
Heard a noise, got my cheap parts store stethoscope, located it and pulled the valve cover in about ten minutes. This is what I found. Borrowed an adjuster and had it back on the road, no problems for many, many miles since.
Why sit around wondering what it might be, asking other people and torturing yourself? Take 20 minutes and go pull the covers. You'll feel better just knowing.

View attachment 1715048867
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The car is over in at my dads shop. I don't have time to drive out and work on it after work. The car is not being driven though so this weekend when I have time I'm going there.
 
doogievlg said:
The car is over in at my dads shop. I don't have time to drive out and work on it after work. The car is not being driven though so this weekend when I have time I'm going there.
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Sorry man, I bet it's no fun at all. Hope it's something simple and cheap. I listened on two devices, but it sounds different on each, though I lean more towards a tap than a knock. Fingers crossed for you.
My intended point was just to let yourself off the hook and check it out.
 
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KnuckleDuster said:
Sorry man, I bet it's no fun at all. Hope it's something simple and cheap. I listened on two devices, but it sounds different on both, though I lean more towards more of a tap than a knock. Fingers crossed for you.
My intended point was just to let yourself off the hook and check it out.
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I'm at a good point in my life right now. I'm single and 26 with a good job. If this turns out to be something major and the motor comes out then it's just going to be time for a stroker kit:)

I would prefer it to be quick and easy though so I can drive it this summer.
 
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I got to thinking about adjusting the valve last on this engine to see if that helps with the noise. Problem is that I have never adjusted valve lash on factory rocker arms that are just stamped out pieces of steel.
 
doogievlg said:
I got to thinking about adjusting the valve last on this engine to see if that helps with the noise. Problem is that I have never adjusted valve lash on factory rocker arms that are just stamped out pieces of steel.
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I did it on a stock 318 many moons ago - IIRC, it's a piece of cake.. just get an FSM and follow the directions
 
doogievlg said:
I got to thinking about adjusting the valve last on this engine to see if that helps with the noise. Problem is that I have never adjusted valve lash on factory rocker arms that are just stamped out pieces of steel.
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I'm lost here. If you have hydraulic lifters and stock rockers....there is NO adjustment. If the lifters are clattering then you need longer pushrods. If the lifters are holding valves open, you need shorter pushrods. Better yet, if this is the case, maybe the heads need to come off and get the stem heights checked and see how far the heads have been decked.
 
A valve tap will have a unique sound that is clicking faster than a rod knock at idle. Usually a "knock" will sound like a knock, but the repetition is less than a "tap" of a valve. I once took a noise diagnosis class when I was a professional auto tech. You start thinking about RPM's and frequencies of the noise of moving parts and that isolates you to the right area to look. A story: a friend had a 70 Sport Satellite with a 383. I was at his garage, he said "man I think my motor is toast" He started it up, it popped pretty regular out of the carb. I said "pull the valve cover, that's in the valve train". We pulled the valve cover and one of the adjustable pushrods backed off to the point that the rocker was I/4 turned and not contacting the pushrod. In effect not even opening the valve. He put it back on and adjusted it, and it ran. But I always wondered why it fell off or backed off. I run the stock rocker shafts, as my cars are street only or "stock". I don't know if Mopars like adjustable valvetrains. It as if they weren't designed for it, something with the valvetrain geometry.
 
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