boater2065
Active Member
Hi all, i have a Merc 5.7 EFI. Recently i have noticed a high pitched noise coming from the engine while it's running. Seems to be more pronounced when the engine is warm vs when it's cold. It doesn't seem to change with change in RPM, it's just a constant high pitched humming sound. I have attached a short video as a compressed .zip file, of the engine starting and running for a few seconds. Really hoping someone might have some ideas as to what this sound might be. Cheers
Jeff
Jeff