need help, knocking noise

[Rugbyfan]

First off, thank you for the response. When I pulled the IM and valve cover, and peered down into the cylinder, I did not see any scour marks on the piston the would be indicative of valve-piston contact, nor did a magnet pull any metallic debris . Is it possible that the stuck portion of the valvetrain is preventing the cam from turning past that point (opening the #4 exhaust valves?) and that is the resistance I am feeling?

[Ceeker]

First off, thank you for the response. When I pulled the IM and valve cover, and peered down into the cylinder, I did not see any scour marks on the piston the would be indicative of valve-piston contact, nor did a magnet pull any metallic debris . Is it possible that the stuck portion of the valvetrain is preventing the cam from turning past that point (opening the #4 exhaust valves?) and that is the resistance I am feeling?

your video indicates a rapping noise indicative of a sticky lifter or probably a dropped valve.

I am not entirely sure about the valve train preventing the cam from turning. it shouldn't. pretty simple set up. I spoke with a buddy of mine and he says if you can't manually crank the car over and there is binding he thinks a valve is stuck open.

I would check the lifter; it's quite possible it might only be sticking.
Find out if there is some lubricant you can put into the valvetrain to free up a sticky valve. Aside from the noise, it doesn't seem like you are damaging the engine with the exception of the spark plug closing.

[Rugbyfan]

with the exception of the spark plug closing.

and that could've just been me gapping it too closely like an idiot.

My finger pointed to a closed exhaust valve because the cylinder was wet on top, leading me to believe that any fuel being injected wasn't being allow to vent.

[Ceeker]

if it is staying closed; remove the valve cover. Crank the motor to see if the cams are spinning. as the motor is cranking put your finger inside to see if the valve is dropping. Do this procedure slowly manually cranking the engine. You have to check this to see if your valves in #4 is doing what they are supposed too.

[Rugbyfan]

I'm not quite sure I follow what you're talking about. Where would I stick my finger to feel for the exhaust valves dropping without pulling the headers?

[Ceeker]

I'm not quite sure I follow what you're talking about. Where would I stick my finger to feel for the exhaust valves dropping without pulling the headers?

ah ok..well that is an option. but I would think maybe you can get at it from the intake side?

[328ijunkie]

Start by pulling cams/trays. Youll be able to tell if a lifter is Fed or a valve is staying open thats not under load.

[Rugbyfan]

Well it's official, I am now totally lost. I decided to do a compression test to see if one cylinder had zero psi and then I would know a valve was stuck open. I performed the test in less than ideal conditions:
I only let it idle to warm up (wanted to minimize revving it)
I ran the test when it was just past the cold mark
and like an idiot I forgot to leave the throttle wide open

Oh well this was just to see if a valve was stuck
the results:
1: 195
2: 170
3: 198
4: 188
5: 195
6: 195

So other than cyl #2 being low (but not alarmingly low, and the car barely burns oil) WHAT IS THIS TICKING COMING FROM? If the motor is revved the ticking increases steadily, which to me says valvetrain. And it doesn't sound like lifter tick, the noise is pretty damn loud. Here's another vid:

[scottinAZ]

I still say collapsed lifter. If it is stuck bad, and there is a LOT of lash, then it could easily be that loud,

Buddy of mine has an M20 that sounds like a damn diesel if the valves are out of whack, yours isnt appreciably louder than his

[Rugbyfan]

Anyone near savannah that wants to take a listen?

[328ijunkie]

:wave
;)

[Rugbyfan]

:wave
;)

unfortunately you're just outside my range. I'm not keen on driving the car, and even with my 100 mile AAA towing I'd still have to pay for a lot more. But I might be making some purchases from you (good for you, bad for me!)

[Mr.SWISS]

That sounds more toward teh rear like clutch/fly that motor knock. I had a car once that sounded like that, one of the tq converter bolts backed out a tad and was hitting the sheet metal dust cover. I know there is a difference in what you are working with but perhaps you didn't grind the pan down enough and it's hitting the fly in one particular spot.......

[Rugbyfan]

didn't grind the pan down enough and it's hitting the fly in one particular spot.......

grind the pan?

[Ceeker]

unfortunately you're just outside my range. I'm not keen on driving the car, and even with my 100 mile AAA towing I'd still have to pay for a lot more. But I might be making some purchases from you (good for you, bad for me!)

never dropped the exhaust to peak into it huh? it's not going to be easy or a miracle to fix man...face the reality..start digging... :-)