Engine size

[Blair Dehuff]

I am interested in the Hunter 320. However, I'm concerned about the Yanmar 18 HP being sufficient capacity for a boat which displaces 8,500 lbs dry. I've noticed that Hunter uses the Yanmar 18 HP engine on smaller boats as well.I sail at a high elevation above sea level at Lake Tahoe, CA (6200 ft), where an average marine diesel engine loses 20 - 25% of its power. I'd be interested in any comments or opinions from Hunter 32 or 320 owners regarding their boat's ability to achieve hull speed with a Yanmar 2GM20 at sea level or at higher elevations. Does anyone know if the Hunter 320 will accomodate a larger engine (i.e the next size up - 27 HP Yanmar)? Does Hunter offer it? Has anyone opted for this?Thanks for any advice.

 

[Steve Dion]

Wouldn't worry about it too much.

Blair:I would not worry too much about the power. Considering that the farthest distance you may need to cover would be 26 +/- miles. Many manufacturers have used this engine in MUCH heavier boats. You do not have to contend with any current only wind. We have a H'31 which is about 1000 lbs heavier and the engine does fine unless we are fighting a current. I don't think you are going to find too many boats that have much larger engines in this class. If you look back at the older Cherubini's (like the H'30 they had 8-12hp engines) and they just do fine.

 

[Kent]

320 engine

Blair, All my cruising has been at sea level so I really can't comment on the higher elevations but the engine has performed great. We recently crossed the Gulf Stream to and from the Bahamas and both the Great Bahama Bank and the Little Bahama Bank with almost NO wind. We were able to maintain about 6.5 knots on the GPS most of the time. We averaged 5.5 knots for the 981 miles according to my gps. Don't know if a larger engine would fit but I wouldn't put one in Giggles even if it did.Kent S/V Giggles

 

[Rick Belew]

18 HP on 320

Can not say about your elevation, buttook a 40 mile trip and set the RPM'sat 3000 and averaged 6 knots. If there was a current it was less than .25 knots. I select the 3K rpm's because the engine ran with very little vibration. Hope this helped.

 

[Stephen Baltes]

18 Hourses are all you should need

I can't imagine needing more than the standard 18 horsepower Yanmar unit. S.M.L. is about 900 feet above sea level and, granted no current or tides to deal with, but she's been wonderful. Only a few hours on mine so far but I've had it up to 6 knots for short bursts with no problems. Plenty of power both in forward and reverse and a real mizer on fuel consumption. I do have the 3-blade prop. And I do not recall any options for engine size on the 320 - looks pretty snug in the engine room as it is!For reference my last boat, a Catalina 28, had about the same displacement and an 18 HP Universal engine.

 

[Bryan C.]

Just enough

As a general rule, HP to move boat hull speed is displacement/1000*2. For your boat that would be 17 HP. Might be a tad light if you load 'er up with a ton of stuff, but based on this test you're close enough.