Knock in New Engine?
Thread Starter
Joined: Nov 2001
Posts: 3,066
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From: Sunny San Diego
Knock in New Engine? Still tuning the car. So idle is still rough. But have been hearing a knock from the engine. I first thought it was my exhaust hitting. But can't find anything wrong. I hope its not the engine.
When I bring the idle up, I can't hear it. So not sure it is the engine. but it sounds nasty.
Going to talk to the builder tomorrow.
Knock
When I bring the idle up, I can't hear it. So not sure it is the engine. but it sounds nasty.
Going to talk to the builder tomorrow.
Knock
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
I didn't notice anything in the oil or on the plug.
Now that it is tuned better, the engine doesn't shake as much at idle.
I don't hear it anymore. So maybe it was something hitting. :dunno:
Now that it is tuned better, the engine doesn't shake as much at idle.
I don't hear it anymore. So maybe it was something hitting. :dunno:
My cam only LS1 was doing the same thing. Wasn't pulling any timing and still ran strong so I ignored it for too long. Ended up being the cam bolts had backed out and the cam was walking. Tore up the cam and lifters and hopefully nothing else, still under the knife. If it's like mine it will get progressively worse.
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Thread Starter
Joined: Nov 2001
Posts: 3,066
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From: Sunny San Diego
CJ came down and helped me try to pinpoint the sound.
He couldn't, so I don't fee so bad.
We started eliminating things. We think the rough idle from the tune is causing the flywheel to make noise. And it sounded alot louder after unbolting the TC from the flywheel.
The engine builder doesn't think its the motor and also thought it was the flywheel.
When the idle is smooth, I don't hear it. So I am not going to worry about it after I get it all tuned up.
Knock from under
Flywheel unbolted from TC
He couldn't, so I don't fee so bad.
We started eliminating things. We think the rough idle from the tune is causing the flywheel to make noise. And it sounded alot louder after unbolting the TC from the flywheel.
The engine builder doesn't think its the motor and also thought it was the flywheel.
When the idle is smooth, I don't hear it. So I am not going to worry about it after I get it all tuned up.
Knock from under
Flywheel unbolted from TC
Thread Starter
Joined: Nov 2001
Posts: 3,066
Likes: 0
From: Sunny San Diego
A little more research and some say that the ARP Flywheel bolts won't tighten down enough on the stock flexplate. And I would need to buy ARP flexplate bolts. Opps
Last edited by Ed Blown Vert; Oct 25, 2009 at 08:13 PM.
Thread Starter
Joined: Nov 2001
Posts: 3,066
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From: Sunny San Diego
Motor mounts are poly are fairly brand new.
Builder verified the tray is spaced.
So I hope its the flexplate bolts. Last engine didn't have them. This new one does.
Builder verified the tray is spaced.
So I hope its the flexplate bolts. Last engine didn't have them. This new one does.
Staging Lane
Joined: Jun 2007
Posts: 96
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From: Webster, MA
possibly piston slap at idle? My import has slap at idle and right around 3000rpm with no load, but under load she purrs like a kitten. Guess it's a harmonic thing... dunno about on a V8, but on the 4bangers, i dont worry much about slap that low since most of the big pulls are done from 6-10k rpm.