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Discussion Starter #1
I noticed yesterday when warming the car up to the burp the cooling system that there was a slight knocking sound coming from the drivers side when cold. After running for a bit it appeared to get less loud if not went away altogether. I assume that if this was a major internal problem the knock would not change pitch after warmed up, a major problem being a rod knock or something. I'm pulling the valve cover tonight to look the top end over and while it's off I'm gonna adjust the valve lash.

Here's my question, would you drive the car if the noise went away when warm? The vehicle seems to run fine, plenty of power, and I really don't want to pull the motor. Possibly related to oil being thinner at start up and then when it get thicker takes up the clearance issue that may be causing this noise? Metal expansion taking up the gap? Thought, comments, or ideas appreciated. I want to enjoy the heck out of the car this summer and don't want to be sidelined for the second year in a row. Thanks guys.
 

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It may just be a rocker....If you can find some old valve covers....Cut the top about a 1 1/2 the length of the valve cover...That way you can run the engine to make adjustments to your rockers without making a mess....
 

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Discussion Starter #3
It may be hard to adjust my rockers with the motor running. I guess I should give some details, it's a solid lifter cam, 1.6 rockers, center bolt valve covers, 383 SBC, aluminum heads, GM 350 block. If that helps anyone.

Was talking with a co-worker and he said if it was serious knock noise, i.e. connecting rod, that it would not get less loud as it got warmer. So maybe I'm OK, maybe it's just a little cold piston slap.
 

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Possibly related to oil being thinner at start up and then when it get thicker takes up the clearance issue that may be causing this noise? QUOTE]

Isn't the oil thicker when cold and thinner when it heats up? Or is my thinking all wrong.
 

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Discussion Starter #5
I guess, I don't know, maybe I'm all wrong on this one. We need an oil guru out there to chime in.
 

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Discussion Starter #6
I am wrong!

Nevermind, it does get thinner when warm. So I guess I'm dealing with a metal expansion thing here.
 

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oil is thicker when cold, might just be the valve lash, which you set when cold on a solid lifter motor, not hat it would matter since the lifters don't pump up
 

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Discussion Starter #8
Lash is slightly off, but I think some may be way off. Going through them all tomorrow as it was getting late. I hope I can still make that car show on Sunday :yes:
 

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Discussion Starter #9
All Good!

Adjusted all the lifters today and the noise is gone!! Thank the lord, I was very concerned, but drove it for about 60 - 70 miles today with no problems.
 
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