replace Atomic 4 with Yanmar YSB8

[russ1302]

has anyone replaced an Atomic 4 with a Yanmar YSB8? I'm considering the swap in my newport 27, but I'm not sure if it's enough engine. Does anyone have any experience with the Yanmar YSB8, in a 27ft boat?

Thanks
Russ

[mhfowle]

I have a ysm 8 on my 26ft. S2. It's very reliable and powerful. I think my boats weighs 5000lbs. It's easy to maintain and the parts are reasonable and redily available. Also Yanmar stands behind their pproducts and offer superior customer service, even on 30 yr. old engines.

[okawbow]

I have a YSE8 in my Bristol 24. The boat weighs 5800 lbs. I use a 12", 2 blade prop. The motor pushes the boat near hull speed, but I've had trouble making good headway in very high winds and waves.

[sailingdog]

Russ-

Why are you replacing the Atomic 4? Is it because the engine is having problems? Or is it because is a gasoline engine???

BTW, IIRC, Beta Marine may make a diesel that is a "drop-in" replacement for the Atomic 4.... and that would significantly reduce the costs of swapping the Atomic 4 for a diesel—since you wouldn't need to replace the engine mounts or prop shaft.

[russ1302]

I'm replacing the atomic 4 because it was siezed when I got the boat, and when I dug deeper, I found the valves are frozen and there is way to many rusted out parts to mess with.

It sounds like I should try to find some thing with a bit more power for my 6000 lbs boat. Or maybe just a different prop?

Thanks
Russ

[sailhog]

Look at the Beta Marine drop-in replacement. They're a lot less expensive than the Yanmar, and are made specifically to replace the A-4. Good luck.

[Valiente]

Beta (which are simply marinized Kubotas, from what I understand) have been getting good reports not just as a drop-in for Atomic 4s, but generally as reliable small diesels that are a shade more intelligently designed, particularly for the typical "lift off the companionway stairs" access option.

I never thought I would appreciate having an engine bay I can simply stand in, but I do, as the thought of hauling my engine anywhere but directly up is fairly depressing.

I think it's a shame that the "engine box in saloon" style has pretty well disappeared. I'm sure modern soundproofing techniques, careful venting, and other methods could make it work. Having the diesel in the middle of the boat not only makes sense (360 degree access), but puts the weight over the keel and closer to the CG. It also means the shaft and prop can exit the boat at a shallower and more useful angle.

But I digress.

[russ1302]

The yanmar is a good used engine, and would cost a fraction of the Beta Marine. The boat isn't worth the cost of the Beta setup. So I'm looking to find an engine and just freshen it up.

Russ

[okawbow]

Many sailboats don't have motors at all. The 8hp Yanmar should push your boat well in most conditions. If you don't sail in areas with strong currents, you should be ok. Just treat the motor as an aid to sailing. I can't understand why some sailors go around the world without a motor, and some have to have 50hp on a 26 footer.

[russ1302]

I sail in the San Francisco bay, and there is a great deal of current in some areas. I will often motor for as much as 45 minutes at a time, in strong currents. So I'm thinking I'll go with a slightly stronger engine. Maybe the YSB12, or a 2 cylinder model.

Thanks
Russ