All Volvo V8s have a problem. It seems Yamaha built the engine and noticed it did run smoothly due to the 30° cylinder bank separation. The vibration problem was solved by fitting a counterbalance [CB] shaft in the valley between the cylinder banks. A sprocket and bearing were added on one end to en...

I remember reading on some forum that someone found a loose bolt inside the upper intake manifold. He replaced the manifold and the noise was gone. I wonder if this may be the issue with mine. it had a similar sound to mine and it went away when he touched the "airflow valve??" I honestly...