First off I'm new to this forum and to mud motors. Got a new 35 GTR with 9 hrs. on it. Since day one it had a dull knocking sound mostly noticeable at idle. At first it almost sounds like a rod knocking but I think it might be the flywheel out of balance or something like that. Is this normal for these motors? Yea I'm new to mud motors but I've had many BRIGGS motors and can't say I've ever noticed this on any of them.