Hey guys, I have just finished up building a VC460 engine and I have encountered a strange knocking noise which seems to be coming from inside the engine somewhere. So far it is all VC parts that came with the engine camshaft as well. Call me crazy but it sure seems to me like it is camshaft gear backlash, or possibly thrust play. I posted a video of me turning it over with and without the rocker arms installed, video explains it all but it does not make the noise when the rockers are off. I have actually run the engine for a short amount of time and the noise is definitely still there and I wouldnt want to drive around the pits at the drag strip with it sounding this bad. "its a pit golf cart for drag car" The noise is very consistent, 2 distinct clinks from each valve as they are closing, 1 on the way down, and another when the valve is all the way down. So this tells me it probably is not the compression release, and probably not valves hitting the piston.
My thought is the lifter is pushing on the cam and it makes a knock as the gear lash is taken up, then the 2nd knock is when the lifter is on base circle of cam and lash is taken up again.
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Have you guys seen this before and any idea on how would I go about fixing it? I would like to find the problem before just blindly replacing parts like a cam hoping it fixes the problem.
Thanks!
My thought is the lifter is pushing on the cam and it makes a knock as the gear lash is taken up, then the 2nd knock is when the lifter is on base circle of cam and lash is taken up again.
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Have you guys seen this before and any idea on how would I go about fixing it? I would like to find the problem before just blindly replacing parts like a cam hoping it fixes the problem.
Thanks!