I will say that it is quieter than the 4-108 it replaced. Because of the V drive transmission alignment is more crittical. Beta wanted me to fit a flexible shaft coupling but since at the time I was unaware of one that would fit my installation Beta recommended stiffer engine mounts that transmit more noise to the hull. Since then I found a Vetus flex coupling that is no thicker than a standard one and put it in but I still have the stiffer engine mounts. Softer mounts would make it quieter still.

When I was shopping engines Beta fit my needs best. It is a little longer and a little narrower than the 4-108. The exhaust is almost identically placed and the same 2 inch diameter. Yanmar requires a three inch exhaust. The Beta is a lot lighter than the 4-108 and that affected the boat trim. I now keep a 140 ft shot of anchor chain in the lazarette to make up the difference. If you have one of those old Volvos where each cylinder is a seperate casting you will be getting a much lighter engine no matter which one you choose.

If I had to do it again one thing that I would re-think is the second alternator installation. I asked them to give me the fastest alternator speed that they could without going over 10, 000 RPM. That worked out to a 3.66 to one ratio. The upside is that even at idle I can get full alternator output and the alternator runs cooler at the faster speed. The downside is belt wear. They fitted a serpentine six groove belt and it produces a fair bit of belt dust. It also shortens belt life. Even Gates green stripe belts only last about a year. Another upside to that is because the alternator runs cooler I don't burn up stators as much as I used to.

I still love that at oil change time the oil is not black. It is not as clear as it was when the engine was new but it is far better than the 4-108.