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Engine knock around 3000 rpm

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TurboSpider

Proven Member
223
16
Nov 2, 2015
York, Pennsylvania
97 eclipse gst. The other day I was getting on it a little harder then usual, normally I baby the car. The next day I noticed a knocking sound coming from the engine if I bring the rpms up to around 3000 and hold it there. It sometimes does it even when just cruising. Here is a video of the sound, it starts around 0:04 seconds in when I rev it up.
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. I am guessing its a rod knock but would like second opinions. I am going to drain the oil to look for shavings this weekend. It sounds like it is coming from the top of the engine just standing over it, but I havent gotten underneath it yet to see if it is louder at the bottom or the top. I can feel the vibration of the knock on the valve cover though
 
This may be just the video but it doesnt rhythmic enough to be an internal knock. Just based on the video and from what i hear from it it sounds just like a knock from the power steering pump that happened to my old roommates gst. Look for any bolts making contact and diconnect the belt for the power steering so the power steering pump wont work and then start it up again and let me known if the knocking continues. Like i said this is just what i can tell from the video
 
It definitely
sounds like its coming from the top of the engine and not over where the pulleys are.
 
Alright sorry hard to tell from the video. A rod knock is usually louder near the bottom of the block rather than the top. A few things can cause a "similar" sound in the head but not as pronounced as a lower knock. Try removing the VC and testing rockers and inspect your cam lobes. While your in there, remove the spark plugs and inspect pistons heads for any marks or excessive carbon buildup. Have you tried a compression test? Just offering simple tested before you lower the pan
 
I also say pull the valve cover. I thought it kinda sounded like a rocker bouncing around, maybe you got a bad lifter. Its hard to tell from a video
 
Ok I pulled the valve cover, I am not exactly sure what I am looking for. I have attached some pictures of what it looks like. Nothing looks of the ordinary. All the lifters seem to be up against the rockers. I pulled the spark plugs. The far left cylinder had what could be metal shavings on top of the piston. Ignore the score marks on the carbon of the piston in the center as that happened from me trying to stick a punch in there to move the metal shavings around, which I really wasn't able to do. I am not sure if the shavings are from removing the spark plug and debris falling in or what. They don't seem to move so they might be embedded in the piston.

Before removing the valve cover, I started it up and put a pry bar against the clutch pedal to stop the throwout bearing from making noise. I also put another pry bar against the gas pedal to raise the rpms up some. I really am having a tough time deciding where the noise is coming from. It seems to radiate from the engine bay. I even listened with a stethoscope. It seems like it MAY be a little louder on the bottom of the engine. However after listening with my naked ear, It sounds actually like it may be coming from the side of the engine with all the pulleys. While I was under there, I noticed a coolant leak dripping off the bottom of the crankshaft pulley or around that area. There was always a leak there but I am not sure if it was ever that bad as you see it constantly dripping in the video. It seems like the sound is maybe coming from the center of the engine on the side with all the pulleys.

I tried to get another video of the knocking sound both on top and on the bottom, but I know it is hard to tell over a video. I checked the tension of the timing belt. It seems to not have gotten any looser since I looked at it when I first bought the car. There is some play in it though, which I figured was normal. Here is the video and the pictures.
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Belt seems a little loose, id pull the cover and check the hydraulic belt tensioner, especially since the sound is coming from the lower pully area.

The debris on the pistons is hard to see, but it may be detonation marks.
 
I recommend changing the tensioner so that it wont skip a tooth later on. Looks like the water pump is leaking as well. Replace the pump, tensioner, and belt at once. Have you had a chance to pull the pan yet?
 
didn't get a chance to pull the pan or do any other work to it yet. I threw the valve cover back on and had a buddy listen to it. He said it sounds like its the bottom end, but I want to check to make sure
 
Drain the oil and let us know what you see in the oil. Sounds like rod knock. Its good you caught it soon. Don't start the engine again until you drain the oil and pull the pan to verify whether it is a rod bearing or not.

Looks like you have more problems than that though. Oil leaks, exhaust leak(i think), oil all over your timing components. Time to take that car off the road and give it some TLC. My timing belts have never had that much deflection.
 
Pulled the pan, bunch of gold chips in the bottom of the pan. The 2nd piston in from the timing belt the rod moves as seen in the video. I guess I am SOL now. I am mechanically inclined and have done motor swaps in the past but never dealt with engine rebuilds or anything. Judging by the amount of gold flakes, the bearing has spun completely. There was some larger pieces but most of it was finer flakes. So what are my options. I guess I could order another crank and rod set up and put that in, or should I just try and get a 6 bolt to put in? Just try and find a complete engine local to throw in?
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Hello friend. Did you able to solve the problem? What was really the cause? I have the same problem too. Hope to hear from you.
 
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