Worrying Engine noises/knock

I pulled plugs and stuck a scope in each cylinder. Everything looks consistent between all 4 cylinders, decent amount of carbon build up but nothing out of the ordinary for an engine with 80k on it. Cylinder walls still had some cross mill marks visible but they looked like the factory boring. (which I was curious about cause the previous owner swore this was a 2.0L.)
Valve operation looked great in the cylinder with no visible damage and looked to be free moving.

Anyway, still looking for problems, nothing is jumping out at me. Suggestions are very welcome, as i'm running out of ideas beyond the water pump (which i have to re-assemble the top before testing).
 
Hmm. there was a posting where someone found the wrong bolt in the cam pulley. (Yes grasping at straws)

? going to put the crank pulley back on and run for a little bit with no belt? (don't run too long with no water pump).

Next time you hear the noise, press the clutch down to see if the noise changes. (yes again grasping at straws) (this will stop the input on the transmission from spinning.)

a little puzzled on the rust color between the lob's on #3 but I do not think that is related.
 
The rust difference on the camshaft surprised me too. I know my clutch makes a lot of whirring noises when depressed, I have a new clutch and throw out bearing (which is probably worn) for it. There is a potential that there is something bouncing around in the bellhousing causing the clunk, but it is very consistent with rotation of the engine.

I will be careful not to run it long without a water pump, already had that belt break on me once and it got pretty toasty fast. I have been hearing a squeak coming from belt driven components for a few weeks, my primary suspect is the water pump.
 
Can you drive the car?
The sounds will probably change under load and may then give away its cause.

But try no belts and depressed clutch first.
 
When you get your valve shim tool, you might want to check that none of the tappets are binding and pop right up when you release them - particularly the ones near the rust on the cam.

I don't know if it is just the photo, but it looks like tappet I3 may have some rust around the edges.
 
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The throw out bearing is always in contact with the pressure plate on an unmodified 87. This makes them wear out relatively quickly. When they do wear out they make a terrible racket - like yours does. (Well actually yours isn't bad at all.) It's very easy to troubleshoot a bad throw out bearing, the noise should go away, or change, when you depress the clutch pedal.
Do the easy troubleshooting tests first.
 
The throw out bearing is always in contact with the pressure plate on an unmodified 87. This makes them wear out relatively quickly. When they do wear out they make a terrible racket - like yours does. (Well actually yours isn't bad at all.) It's very easy to troubleshoot a bad throw out bearing, the noise should go away, or change, when you depress the clutch pedal.
Do the easy troubleshooting tests first.
The noise on my X gets much whirry-er and louder when the clutch is pressed in. When you shift at decent rpm it almost sounds like a small blow off valve!
 
The 2nd wire. It sure looks like the wire which goes to your O2 sensor on the exhaust. If that is not hooked up, the car will run and start when cold, but once it warms up it will be way too rich. What did the timing light say for advance?
 
The 2nd wire. It sure looks like the wire which goes to your O2 sensor on the exhaust. If that is not hooked up, the car will run and start when cold, but once it warms up it will be way too rich. What did the timing light say for advance?
Have not gotten it re-assembled to check ignition timing, still have the valve cover loose. I hooked up the O2 sensor again before bringing it in the garage, I think it will help having it hooked up but probably is not the cause of my worrying noise.
 
The noise on my X gets much whirry-er and louder when the clutch is pressed in. When you shift at decent rpm it almost sounds like a small blow off valve!
OK, it sounds like you might have an issue with your throw out bearing. The whirry sound is the bearing eating itself up under load. If it wears much more the rattling sound you hear when the clutch pedal is not depressed will get much louder, and much more annoying. You'll also cause small children and dogs to avoid your car as they will think it's about to blow up!
 
OK, it sounds like you might have an issue with your throw out bearing. The whirry sound is the bearing eating itself up under load. If it wears much more the rattling sound you hear when the clutch pedal is not depressed will get much louder, and much more annoying. You'll also cause small children and dogs to avoid your car as they will think it's about to blow up!
Intimidating ones' surroundings sounds like a positive if it didn't potentially result in complete clutch failure! :)

I am trying to decide when i want to take care of that clutch, maybe I should just get it over with and pull the transmission.
 
Others correct Me if I Am wrong. If we are thinking throw out bearing, removing the spring (arm to bell housing bolt) and holding the arm away from the bell housing, This would make the noise go away as it should pull the bearing off the fingers. (when done install the spring the correct way, not arm to bell housing).
 
I know this isn't the best solution, but have people evenly shaved off a couple thousandths off the bottom (not the side the cam rides on) of the shim? Only thinking about this cause I'm at most .002 out of spec.
 
Well, one step forward two steps back. Got the engine back together and put the accessory belt on. Went to start it up and it ran like utter garbage, lots of smoke running like it was on three. Started disconnecting ignition wires and every wire made it then sound like it was running on two, all affected the engine noise. Also looks like there should be a plunger in the middle of the distributor cap where there is a spring, I could not find it but made a replacement with a fuse end. When i was turning the engine it looks like one of the clips that holds the cap on the distributor jumped up into the distributor and messed them up.

Was trying to figure out what happened, pulled distributor cap to see the four star like points under the rotor were bent to hell. Bent them back and tried to start it and it would not fire, put a timing light to it and no spark at all.

Guess its back to the basics, gotta figure out what happened to my spark.
 
You've bent the hall effect sensor, it triggers the ignition as the fingers pass the static fingers; the clearance is fairly critical.
replacement parts are available, not especially expensive; it's a common Bosch system.

Oh, yeah, get a new cap.
 
You've bent the hall effect sensor, it triggers the ignition as the fingers pass the static fingers; the clearance is fairly critical.
replacement parts are available, not especially expensive; it's a common Bosch system.

Oh, yeah, get a new cap.
Yeah i figured. I can find a new cap without issue but finding the hall effect rotor is a bit of a pain. Ugh, apparently there is supposed to be a cover in there to prevent this. Previous owner removed it and looks like my own ignorance bit me :|

Oh well, lesson learned. A mistake I will not make again.

Anyone know where i can find a replacement hall effect rotor?
 
I got this from ebay 2 years ago
IMG_1217.JPG
I ended up using another distributor, so I have one of these too
IMG_1215.JPG
PM me, lets make a deal.
 
Look at the schematic in the catalog before you disassemble the dist. There is a tiny roll pin that locates the trigger wheel on the shaft. Remove the dist to do this work. You will be buggered if you drop the roll pin into the dist guts or worse lose it elsewhere.
 
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