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Old Feb 28, 2007 | 08:54 PM
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Default Engine knock

Could a loose plug wire sound just like a rod knocking?
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Old Feb 28, 2007 | 10:06 PM
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Actually that's how you would tell what cylinder the knock is coming from. If you hear a knock, start pulling wires from plugs one at a time until the knock diminishes. If you have a true knock it's very possible you have a worn rod bearing.
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Old Feb 28, 2007 | 10:08 PM
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Originally Posted by bmankin
Could a loose plug wire sound just like a rod knocking?
Nope
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Old Feb 28, 2007 | 10:43 PM
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It's a fresh rebuild. Just wishful thinking. A loose plug wire is the only thing I have found wrong so far. Oh well.
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Old Feb 28, 2007 | 10:59 PM
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From: In the shop most of the time,,, And it BEER TIME somewhere
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Loose rocker arm,,,,
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Old Feb 28, 2007 | 11:04 PM
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Did you properly break-in the cam?
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Old Feb 28, 2007 | 11:37 PM
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Originally Posted by dgruenke
Did you properly break-in the cam?
I think so. If not could that cause it to knock? I suppose it could be a lifter jammed up in the bore but it sounds like something in the lower end. Its hard for me to tell exactly where its coming from. I think I'm just going to pull it and make sure. I'm about half way there anyway. I can have it out as quick as I can put everything back together. This has gone from a project car to a career.
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Old Mar 1, 2007 | 09:34 AM
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From: In the shop most of the time,,, And it BEER TIME somewhere
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Pull the valve covers off and have a friend bump the engine over a little at a time and look at all the rocker arms to see if they are all going up and down. Also at this time, make sure none of them are too loose.
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Old Mar 1, 2007 | 09:40 AM
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That's my thoughts too. some part of the valve train is maybe not adjusted enough or too much.
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Old Mar 1, 2007 | 10:26 AM
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Couple more thoughts......exhaust leak at the manifold....fuel pump pushrod. Both give that lower end sound.

Last edited by goinbroke; Mar 1, 2007 at 01:11 PM.
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Old Mar 1, 2007 | 10:32 AM
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Originally Posted by BLACK SHARK
Loose rocker arm,,,,
Yep! Definitely a possibility!
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Old Mar 1, 2007 | 10:33 AM
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Originally Posted by goinbroke
Couple more thoughts......exhaust leak fuel pump pushrod. Both give that lower end sound.
i was going to ask if you installed a new fuel pump.
when going bad they make a nice bottom end knock
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Old Mar 4, 2007 | 12:15 AM
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New fuel pump and I checked the rocker arms over and over. I was looking for a paint shop when this happened. The machine shop came to my house and listened and agreed it was in the bottom. I think they will take care of me even though I assembled the engine. I am going to will play it safe and take the engine to them. I am just fortunate that I do not have to do this over a brand new paint job.
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Old Mar 23, 2007 | 08:43 PM
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The first rod bearing was wasted. Machince shop advised appeared to be red thread lock. I noticed chunks of redish brown plastic when I drained oil but I could not figure out what it was. Heres the quote
Assembly/Disassembly $350
Turn crank aprox .30 under $150
Gasket Set $70
Rod/Cam and Mains $70
resize 1st rod check the rest $72

Does this sound fair?
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Old Mar 23, 2007 | 08:50 PM
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Originally Posted by bmankin
The first rod bearing was wasted. Machince shop advised appeared to be red thread lock. I noticed chunks of redish brown plastic when I drained oil but I could not figure out what it was. Heres the quote
Assembly/Disassembly $350
Turn crank aprox .30 under $150
Gasket Set $70
Rod/Cam and Mains $70
resize 1st rod check the rest $72

Does this sound fair?

That sounds right on the mark for a shop's rate at labor and parts. Being able to do this work yourself will save you lots of money but when you can't you have to rely on the ones that can.

Go for it, and consider it money well spent.

Or...

Save that money, put the Vette away for a while, and build or buy a new motor to replace the one that's in it. Other parts will wear or go bad and it'll nickel and dime you to death by the time you just rebuild the whole thing a little at a time.
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