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Discussion Starter · #1 · (Edited)
Guys, I need some help on how to go about adjusting the valves on a 454 bb engine in my Wellcraft Nova.
I had this engine rebuilt last year and it only has 1 hour run time on it.
I fired it up for the first time this season and there was a clattering noise coming from the rocker cover, metal hitting metal. I removed the rocker cover and found that a rocker had come loose,off the spring.Almost all the rockers were slack .
I tried my hand on tightening them by rotating the crankshaft pulley until each spring was fully UP, tightened the nut just enough so the push rod could not spin then tightened the nut 1/4 .
After completing one bank, went back to re-check what I did and they were all slack again. re did them again. Tried firing the engine up with no luck, allot of back firing

Any help would be great.
 

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Buy a remote starter switch from autozone etc. Start on one side in the front or back. I always start at one end and work to other. Tap the motor til the pushrod goes down. It sounds like you are trying to do it with the lifter/pushrod up (on top of the lobe). With pushrod down wiggle the rocker from the pushrod to the valve and tighten the nut until the slack is out. Go a half turn more and you are done. Move on to the next on.

Remember tighten the rocker to get the slck out then half turn. Don't bottom lifter out the tighten because you'll just have all the valves open.

Hope this makes sense and helps.
 

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if its a stock 454 you do not have adjustable rocker arms.

Is there a allen head in the middle with a locknut?

Or just a bolt? ( non adjustable )
 

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Go to Comp Cams website and follow the instructions. You need to set the rockers when the cam lobe is at the bottom of the stroke. You need to set the intake valve when the exhaust starts to open and the exhaust when the intake is almost closed. If they were set correctly when the engine was built you have probably wiped out the cam. I have a new cam for my dad's 454 in the floor now due to damaging a lobe during break-in. Premature cam wear is a commom problem with the oils we now have available.
 

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Discussion Starter · #6 ·
Fixed the problem, she now purrs like a kitten :yawn: This engine sounds quiet and gutless.Good thing it's up for sale.
The instructions in the link above is fool proof, the engine fired up in one try and was Idling on it's own.
I'll post some pix of the job later.
Thanks for the input guys.
Steve
 
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