Engine knock - 96 Firebird Formula
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Engine knock - 96 Firebird Formula I had a friend tell me my engine knock sounded like a loose rocker. It would only knock when you would take off or rev it to about 2500 to 3000 rpm but once you reach speed you couldn't hear it. I took off the valve covers and wiggled the rockers but they didn't have a lot of play. I wanted to check the rods for bends so I took them out cleaned them up and every looks good. I'm have trouble putting it back together though. I made sure to keep track of which rod and rocker came from where but when I'm trying to get zero lash its making the rod feel tight without the rocker bolt going down. I didn't cause any damage yet but can anyone tell me how to put my pushrods back in and tighten the rock back down?
You need to be careful and pay close attention when you're adjusting valves. Here's a very helpful guide.
http://shbox.com/1/4th_gen_tech2.html#adjust_valves
http://shbox.com/1/4th_gen_tech2.html#adjust_valves
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You need to be careful and pay close attention when you're adjusting valves. Here's a very helpful guide.
http://shbox.com/1/4th_gen_tech2.html#adjust_valves
http://shbox.com/1/4th_gen_tech2.html#adjust_valves
Last edited by Cody Ayers; Oct 4, 2018 at 04:00 PM. Reason: Extra words
Don't spin the pushrod. It's too inconsistent. push/pull/wiggle pushrod up/down while tightening adjusting nut and stop at the very moment there is no more play. Just ensure you are on the base circle of the cam lobe when doing this.
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Appreciate the help, how do I make sure I'm on the base circle of the cam lobe? Do I just keep it in the the middle of the hole?
Last edited by Cody Ayers; Oct 4, 2018 at 04:32 PM. Reason: Edit
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Valve train adjustment is not rocket science.....but the motor sure can go "boom" if you FU the process.
You need to rotate the motor as described in the methods in the link so that the valve you are working on the cam is on the center of the base circle
If you have poly locks for the RR just tighten them with your fingers until there is no more Up/down movement of PR then add 3/4 turn of preload by tightening the poly lock then tighten the alan head while holding the poly lock in place
Just remember that if you go back and check the preload again. the push rod will be a little loose because the lifter plunger will pump down a little, Ive seen people keep adjusting the preload until they bottom out the lifter
