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Sudden Loud knocking

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Old 01-01-2012, 12:27 PM
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Default Sudden Loud knocking

Hello all-

Driving home today, the car suddenly began knocking very loudly. I then limped my car home as I was less than a mile away. The noise is rhythmic and the speed increases with the throttle. The knock can be felt in the tunnel and by the firewall. I initially suspected a problem with the clutch and flywheel, but after some searching, I'm beginning to suspect a failed lifter or some sort of major failure in the engine. The engine still has oil.

If I were to remove the oil filter and cut it open, is there anything I could look for to tell if the problem is in the engine? My reason being, if the problem is engine related, I will likely just park the car until I can afford a new motor. If it isn't, I will just fix it now. I don't have the room or the know-how to remove and rip apart the motor.

Thank you guys in advance.

Jacob
Old 01-02-2012, 01:12 AM
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if you are going to cut the filter open you are going to want to look for copper type metel in the filter/oil if you find that, you had a bearing failer somewhere and the motor will need a rebuild.
Old 01-05-2012, 03:23 PM
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Drained the oil and cut open the filter. No bearing material or metal anywhere to be found. A buddy suggested it could have been a failed starter gear return spring, but the starter appears to be normal with no irregular wear. Here is a video I caught while I could stand listening to the engine like that. The knocking is much louder than the video suggests. I'm open to ideas.

http://www.youtube.com/watch?v=F07ci...j_gl79XeWVgU6Q
Old 01-05-2012, 07:55 PM
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sounds pretty nasty. i would pull the valve covers and see if you dropped a valve.
Old 01-05-2012, 07:59 PM
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^^^^this. look for any that are a different hieght with the rockers off.
Old 01-05-2012, 08:03 PM
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It does sound like something is bouncing around in there. Like polt said, just pull the valve covers and check your top end. It's the easiest thing you can check right off the bat.

Does it sound like it's coming from a certain side at all?
Old 01-05-2012, 10:05 PM
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Any Check engine light? Check for missfire codes. Had this happen to me 2 times and was a bent pushrod and the other was oil was to thick believe it or not.
Old 01-05-2012, 10:08 PM
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Plus a failed lifter wouldn't be that loud. Try pulling spark plug wire by wire and see if it quiets down u have a bent push rod. If not pull the covers and check if any rocker arm bolts stripped off. Were u driving it hard when it happened?
Old 01-05-2012, 11:18 PM
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No CEL and can't really tell what side its coming from. It's just too loud to isolate really. I was driving it moderately hard maybe 15 minutes before it happened, but when it started, I was cruising at around 30-35. I'm going to be pulling the valve covers tomorrow. I'm still unsure of what to look for. How would a bent pushrod present itself?
Old 01-05-2012, 11:39 PM
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When you pull the covers, look for any loose rocker arms or valve stems that look off center from the rocker, or springs that have come off.
Old 01-05-2012, 11:44 PM
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I see, thanks guys!
Old 01-06-2012, 11:32 AM
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Got em.
Old 01-06-2012, 11:46 AM
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Failed rocker. Good job man. Told ya, it was easy ehh?

Now get a new set of quality rockers. Luckily you didn't drop a valve and it was just that rocker.

What rockers are those?


EDIT: Just my opinion, but if 1 failed like that, I would have zero faith in the other rockers and that company. I would change them all, but that's just me. Glad you figured out the problem and it isn't catastrophic.

You're probably gonna need another push rod also. That one was surely slamming into the valve cover and is probably damaged.

Last edited by sepsis; 01-06-2012 at 12:28 PM.
Old 01-06-2012, 12:11 PM
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Default Rocker Arm

All I can say is damn that sucks
Old 01-06-2012, 12:43 PM
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Originally Posted by sepsis
Failed rocker. Good job man. Told ya, it was easy ehh?

Now get a new set of quality rockers. Luckily you didn't drop a valve and it was just that rocker.

What rockers are those?


EDIT: Just my opinion, but if 1 failed like that, I would have zero faith in the other rockers and that company. I would change them all, but that's just me. Glad you figured out the problem and it isn't catastrophic.

You're probably gonna need another push rod also. That one was surely slamming into the valve cover and is probably damaged.
I forgot how easy it was to pop the valve covers. I have more trouble getting the oil filter off with my long tubes than I do popping the valve covers.

The rockers were Yella Terras. I got them after my stockers fell victim to a failed deck on an over-ported head, and figured they would give me the faster revving motor I want. I'm most definitely changing all of them, as someone just offered me a set of rockers for free.

The car community delivers again. Thanks guys!
Old 01-06-2012, 01:40 PM
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Yet another YT failure.

Good **** though man, glad to see it's gonna work out for you.
Old 01-07-2012, 01:33 PM
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What rockers are you going with?
Old 01-07-2012, 02:00 PM
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Noob Question of the day: Shouldn't you have to worry about all the metal pieces floating around in there?
Old 01-07-2012, 08:01 PM
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Originally Posted by sepsis
What rockers are you going with?
Just picked up a set of stockers. Going to send them out to either Harland Sharp or Colorado Speed to get the trunion upgrade.

Originally Posted by BlaskO
Noob Question of the day: Shouldn't you have to worry about all the metal pieces floating around in there?
Yes. That is the next step, along with checking the intake for any damage from the backfiring. Unfortunately, Yella Terras are aluminum so I can't use a magnet to try and find that piece. I may be pulling the oil pan soon. At least I still have my short block though
Old 01-07-2012, 08:06 PM
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Best of Luck, Buddy


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