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73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: bigben5054 on June 07, 2021, 07:31:01 am

Title: Engine Knock
Post by: bigben5054 on June 07, 2021, 07:31:01 am

Have an engine knock and wondering if anyone can identify it before I tear back into this thing.  Only does it once fully warmed up.  Can hear it very well standing above engine, but lay under truck with ear close to oil pan and can’t hear it.  Speeds up with throttle.  Not sure what it does under a load.  Have tried to copy link to YouTube clip below.  Thanks.

https://youtube.com/shorts/REn-9D66e5E?feature=share

Title: Re: Engine Knock
Post by: Mike81K10 on June 07, 2021, 10:55:19 am

Sounds like a loose rocker/valve. Get a small pipe or hose and hold one end to your ear and the other put up to each valve cover to see which side it is on. Take off valve cover and adjust. The loose rocker knock should get faster with acceleration and louder. Fix prior to driving anymore before you throw a rod and have real trouble.