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Discussion Starter · #1 ·
Okay, I got the 331 up and running and it was quiet for a minute or two, then all of the sudden there was a loud knocking that was rather fast pased. I shut the engine down, let it sit for a minute and then fired it up again. When I did, it knocked as soon as it fired up, then it stoped. WTF! Anyways, I have no clue what this is. I have 185 AFR heads with Trick Flow 1.7 roller rockers and the stock valve covers, but I had already cut out the oil baffle b/c I ran stock valve covers with my old Crane 1.7 roller rockers and they cleared fine. Anyways, I then took my valve covers off to run the engine without them to see if they were knocking. They knocked for a second again as soon as the engine fired, then it was quiet again. The knocking comes and goes. There is play in all of the roller rockers when the valvesprings are not compressed. Should there be this play? I can wiggle them back and forth. They are stud mount roller rockers. I hope someone can help me diagnose this. Josh
 

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Discussion Starter · #2 ·
anyone? ttt
 

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how long has the motor run? it takes a few minutes to pump up the lifters and all the other stuff to settle in to place. after that it should get quiet.
What cam do you have? lift/duration?
 

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i agree with the lifters, usually when rebuilding an engine you're supposed to let hydraulic lifters soak in oil overnight before installing them.

Aaron
 

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Discussion Starter · #5 ·
i let the motor run for about 10 minutes and get warmed up...then it started getting all funky like that on me. i pulled the lower intake and the passenger side head tonight adn there is a small piece of "something" that is up inside the head on top of the valve on the #1 cylinder. There are also a couple of pieces of this crap on the driver's side too, but I didn't have enough time to pull it, cuz I gotta get to $2 Tuesdays @ the strip club..hahahaha Anyways, I'll pull the lifters too, soak them in oil for a few days, while I get this put back together and then re-adjust the rockers and see how she sounds. The valves and the pistons only have a couple of scuffs on them, but there are no knicks or pits in them. Any guesses? josh
 

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knocking

Josh,

did you ever find out the problem my brotherinlaw is having the same problem
 

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Discussion Starter · #7 ·
Yes, I did. What had happened, was a few tiny pieces of my old pistons that shattered from my old motor had gotten stuck inside the upper intake manifold after i shut the old engine down for the last time. Then, when I bolted the upper intake to the new motor and fired it up, it took a second to suck those pieces down into the motor and they got sucked into my heads and the valves/pistons were slapping them. Luckily, I didn't bend any valves or anything like that. I even took my valve covers off and ran it like that for a while, and the problem still persisted, so I knew I had to tear the heads down. I dont' know if this will help his problem or not, but thats' what mine was. Josh
 
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