Solved - bad engine noise!!

Markos

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Can the magnet reach if you rotate the crank until you get closer to TDC? Even if you use a vacuum you will want it close
to the omit hole. Sorry if captain obvious.
 

Stevehose

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Can the magnet reach if you rotate the crank until you get closer to TDC? Even if you use a vacuum you will want it close
to the omit hole. Sorry if captain obvious.
It’s not the depth thats a problem its the angle down from the spark plug hole. Its easier to move the magnet and camera around when it’s at the bottom of piston travel. But when I feed the magnet down the passageway of the head, through the plug hole, the angle down to the passenger side of the cylinder is proving difficult. I did turn the engine over in each cylinder while looking at the camera and saw nothing in there moving around. Am working on a vacuum attachment now. Will also feed the camera down the intake manifolds later. I’m wondering if the missing nuts on the carb inlets are a head-fake and I have something else going on entirely.
 

adawil2002

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A mutual friend had a broken rocker eccentric which created such a clatter, I sprang from my bed to see what was the matter. What to my wondering eyes did appear, the adjuster nut just wasn't there. Down in the sump it luckily appeared, it hadn't made its way through the cylinders. Pulled the cylnder head to replace all these things, it cost quite a bit & his head it did spin. As he paid the bill with a furrowed brow, he was glad it was fixed anyhow. Then off he drove off with a wink in his eye, the highway is calling it's time to fly!
 

x_atlas0

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Andrew's point about checking the pan is a good one.

Is the noise still present if you start the car?

For the front of the engine, if the rockers seem good, are you running the distributor? Are all the bolts present and torqued on the cam gear? I have also heard about the oil pump securing bolts coming undone, as well as the oil pump sprocket being loose, even though it's got a reverse thread on the securing nut. (as I recall)
 

Stevehose

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Andrew's point about checking the pan is a good one.

Is the noise still present if you start the car?

For the front of the engine, if the rockers seem good, are you running the distributor? Are all the bolts present and torqued on the cam gear? I have also heard about the oil pump securing bolts coming undone, as well as the oil pump sprocket being loose, even though it's got a reverse thread on the securing nut. (as I recall)
All rockers, rocker pads, and nuts in tact. No noise from the distributor. Oil pump chain/sprocket looks in place and moves smoothly when cranked, and I get lots of oil coming out of the spray bar.

It was making noise when I got it to my garage. I turned the engine off to check for fan blockage etc. The I restarted for the cylinder drop tests and the noise was there when I did that. If I find nothing in the cylinders then I will put the valve cover back on and start it up for further diagnosis.
 

Arde

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Andrew's point about checking the pan is a good one.

Is the noise still present if you start the car?

For the front of the engine, if the rockers seem good, are you running the distributor? Are all the bolts present and torqued on the cam gear? I have also heard about the oil pump securing bolts coming undone, as well as the oil pump sprocket being loose, even though it's got a reverse thread on the securing nut. (as I recall)
I recall you built a rotisserie for your E9. With that one could put the car upside down and rely on gravity...
 

Stevehose

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The only sign of trauma I can find is in #5 cylinder. In order for the nut to make it into this intake is for it to fall straight back for about 3.5 inches. Possible? I guess in a "magic bullet" sort of way:

IMG_2814.jpg



Here's a look inside, note the fresh looking marks on the top of the cylinder, and the condition of the cylinder wall. Keep in mind, I drove about 1/4 mile with the noise so I would think there would be more nastiness than this:

IMG_2806.JPG


IMG_2809.JPG


IMG_2811.JPG



I have scoped and magneted it thoroughly with no luck. Maybe I chipped this with the magnet probe. Thoughts? It might be time to put the valve cover on and start it up again.
 
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Markos

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Piston looks more like a 2” scrape which would be hard to do with a loose bolt.

Can you do this or bad idea? Note the towel keeping the oil away from the exhaust. Not that the exhaust would be that hot to start.
 

Stevehose

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Piston looks more like a 2” scrape which would be hard to do with a loose bolt.

Can you do this or bad idea? Note the towel keeping the oil away from the exhaust. Not that the exhaust would be that hot to start.
Yes, but the M30 the cam gear and chain throws oil all over the place. I made a shield once to film my oil sprayer bar but threw it out because it was a one use deal. I may make a better one this time that fits better. Good idea.

 

stphers

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Can u position the bore scope so it can see the valves? How about turning the eng over by hand so that one intake valve is wide open and have a look down the carbs and intake at the intake valve seat at least a bit of it I don't see anything on the top of the piston that is hitting something, nothing embedded into the top of the piston.

May sound crazy but if the noise is gone, try banging the exhaust to see if something has gone rigt thru and is now sitting in the bottom of the exhaust. I did see a 6 mm nut go in thru the intake, banged around just a little and went out thru the exhaust!!

Thanks, Rick
 

Stevehose

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Can u position the bore scope so it can see the valves? How about turning the eng over by hand so that one intake valve is wide open and have a look down the carbs and intake at the intake valve seat at least a bit of it I don't see anything on the top of the piston that is hitting something, nothing embedded into the top of the piston.

May sound crazy but if the noise is gone, try banging the exhaust to see if something has gone rigt thru and is now sitting in the bottom of the exhaust. I did see a 6 mm nut go in thru the intake, banged around just a little and went out thru the exhaust!!

Thanks, Rick
I will do this for the exhaust valves tomorrow, I checked all the intake valves, they move freely and look like this:

IMG_2803.JPG


I am making a fiberglass shell using the end of my valve cover as a mold, enough to bolt on and cover the timing chain and sprocket from oil spray. Then I will start it and video the sound and the valve train as well as try to get a better idea of the source. @dang is providing popcorn.
 
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