Help me with valvetrain noise before i go insane...please
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Help me with valvetrain noise before i go insane...please
This is on a 98 silverado 383 but i figured maybe someone would have some advice, the way the valve train works is still pretty similar. Ok here is what happened, the engine is brand new and i just got it running last week. Amongst start up there was a lot of valve train noise which got worse as i drove which turned out to be one of my roll rockers coming loose. I pulled the rocker off and it gouged the side of the rocker and part of the self aligning washer lookin things, the roller seemed fine however. I put it all back together and started it up and it seemd to have a knock/tick comming from the passenger side of the bay (which is the side the rocker fell of on) so i drove it for a few more days and the noise continued, I then reset the preset on all the rockers and the noise was still there. After that i decided to switch the bad rocker with a good one from the other side. After that the noise seemed a little better and it sounded like the deeper noise was comming from the drivers side and there was still a tick from the passenger side. I decided to proceed with the engine break in and hope it would go away after break in when i got on. Well i finished with break in and got on it and the noise is still there and it seems more consistant then before (before it would kind of fade in and out). Im wondering if the rocker on the one side needs to be replaced and maybe the pushrod on the other side is damaged. What do you guys think and what kind of noise would a bad roller rocker make? Would a pushrod cause a ticking noise? both noises seem to increase in speed but don't get louder with increase in engine rpm
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I bought it off of a freind. It was a used block that was fluxed and then vortec heads that where rebuilt with guides, valves, seals, new springs, screw in studs etc etc. Everything else inside the motor is brand new except the rockers (new stuff is cam, lifters, pushrods etc) Its the lt4 hotcam and then crane cam 918 springs i think with lt4 lightweight retainers. The engine had been sitting for about a year since it was built i would say but was covered in a garage and the uper end was completly dissassembled before it was ran
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Originally Posted by Fandango
Are the heads modified to run the lift of that lt4 cam? I am pretty sure those heads(when stock) can only accomodate .450" of lift.
the noise only sounds like it is from one lifter/rocker/pushrod/ just don't know what is causing the noise and it kinda makes it sound like a diesel and im sick of hearing the noise... it is definately valvetrain somewhere to
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Originally Posted by chevymec
When you broke in the motor did you prime the oil pump and made sure that oil came up to all the rocker arms? Also I'd say recheck the pushrod from the bad rocker arm came from.
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bolt on some stock 1.5 self align OE rockers,they should be cheap and good used one near free.Anything other than OE rockers the valve covers have to be modded for clearence,hopefully you dont have a ton of metal that went thru the motor because the rockers rubbing inside the valve covers.I am guessing you have 1.6 golds,I seem to hear storys about 1.6s from time to time, check to see if rockers are hitting the tops of the retainer or keepers,or if the self-align guides of the rockers are hitting the tops of the retainers.checked for correct push rod length?