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Looking for knocking noise driver side

wahya

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I recently installed a new carb and while I was running the motor, a noise, like a knocking, but a bit of a lighter pitch. It kind of sounded like the same sound when I tapped on one of the pipes on my headers. The only other thing I did recently was change my oil. I had been running Valvolene 20w50 racing oil with zinc. I found out that my local store had straight 30 weight Valvolene. I'm running solid lifters.
BTW, I am using my old 318, now ported with larger valves, heads. The motor was built about ten years or so ago.
I decided to pull the driver side valve cover and while looking at the rocker arms, I noticed that by moving a few of the arms, without pressure on them, from side to side made about the same sound. I don't know if the running engine would cause this sideways motion, but, it looks like these arms are going to need attention, as I think I have found a crack in one of them.

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id disconnect one plug at a time and rule out a header leak

I also once had an exhaust leak at the cross over
 
You are not running solid lifters with those rocker arms.
So, living on borrowed time here, or the guy told me wrong? He said he was building it with flat tappet cam and solid lifters and he told me that I would have to use zinc additive or I wouldn't get far. Would having these non adjustable arms cause some of these arms to appear to be shaped differently. I have not taken these covers off before.
 
Yeah, you are not running solid lifters with those rocker arms. As for the noise, usually if one of the pictured rocker arms fail, a pushrod blows through the cup. Are you sure that something didn't get dropped in the intake when changing the carb? All fasteners accounted for? Those should be stamping marks on the rockers that look like cracks. Yes, they can probably move side to side if unloaded. The rockers are left and right accordingly.
 
id disconnect one plug at a time and rule out a header leak

I also once had an exhaust leak at the cross over
I've got new gaskets coming today. I tried just spinning motor without starting it and started to make a mess.
 
Yeah, you are not running solid lifters with those rocker arms. As for the noise, usually if one of the pictured rocker arms fail, a pushrod blows through the cup. Are you sure that something didn't get dropped in the intake when changing the carb? All fasteners accounted for? Those should be stamping marks on the rockers that look like cracks. Yes, they can probably move side to side if unloaded. The rockers are left and right accordingly.
Pretty careful with covering intake after carb removal. Never say never though.
 
So, living on borrowed time here, or the guy told me wrong? He said he was building it with flat tappet cam and solid lifters and he told me that I would have to use zinc additive or I wouldn't get far. Would having these non adjustable arms cause some of these arms to appear to be shaped differently. I have not taken these covers off before.
If you had solid lifters with that valve train it most likely would not run. Valves would be severely out of wack and either be hanging open or rattling like hell.
 
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