Pilot 30 Cruising Speed- How fast are you going ?

[nveater]

So I have 1999 Pilot 30 with a Cummins 6BT 210 hp engine- this is my 3rd season with the vessel after 37 years with various sailboats. As a former sailboat guy I'm thrilled anytime I'm above 5 knots, but it has gotten me wondering at what other Pilot owners are running their boats at. At 2400 rpm (WOT is 2650), I am cruising in the 11- 12.3 kts range ( yes I have seen higher up to 15 kts, but not very often). I do like to throttle back and cruise in the 9-10 kts range. I realize that this Cummins, a very reliable engine, is probably the smallest hp engine for the pilots and that later iterations with the Yanmar had a bunch more HP. So I would love to know if other Pilot owners with this model engine are seeing similar speeds? More curious than concerned -

Thanks

 

[Mainship Pilot]

2004 Pilot II 30, 6LPA 315 Yanmar, I typically cruise at 2800 rpm's, with a tow, 11' 325# console style dingy behind. I keep it there around 14 knots, as the dingy likes that speed. If not towing, I gain about a knot, at 3000 RPM's, it's a 16 knot cruise, depending on wind and sea conditions.

 

[Mainship Pilot]

2004 Pilot II 30, 6LPA Yanmar, I typically cruise at 2800 rpm's, with a tow, 11' 325# console style dingy behind. I keep it there around 14 knots, as the dingy likes that speed. If not towing, I gain about a knot, at 3000 RPM's, it's a 16 knot cruise, depending on wind and sea conditions.

 

[nveater]

Thanks very interesting that extra 100 hp from Cummins to Yanmar, very nice

 

[DavidM]

Well, that same Cummins block can be had with 380 or even 425 hp.

The Yanmar 6LP at 315 hp is a perfect match for that boat.

But enjoy your Cummins 210 hp engine. You could run it at wot and it probably wouldn’t hurt it at all. That is according to Tony Athens, the Cummins guru on Sbmar.com.

210 hp should push it to similar speeds as the Yanmar at 2,800 rpm.

David

 

[Mainship Pilot]

Well, that same Cummins block can be had with 380 or even 425 hp.

The Yanmar 6LP at 315 hp is a perfect match for that boat.

But enjoy your Cummins 210 hp engine. You could run it at wot and it probably wouldn’t hurt it at all. That is according to Tony Athens, the Cummins guru on Sbmar.com.

210 hp should push it to similar speeds as the Yanmar at 2,800 rpm.

David

David, Assuming your last statement, the 6LPA burns about 7.5 - 8 GPH at 2800rpm in my Pilot 30. What would you guess the Cummins 210 would burn at that same RPM, assuming that's WOT or thereabouts?

 

[DavidM]

Well, your 6LP makes about 18 hp per gpm of diesel so it is producing about 8*18= 144 hp, much less than the Cummins at wot- 210.

If they were both making the same hp, the fuel burn would be about the same.

Remember, the Cummins makes its maximum hp at about 2,600 rpm, your 6LP makes it at 3,800 rpm.

David

 

[nveater]

So for fuel burn- I ran my Cummins pretty much in the 2400 range the first two years I had it and I was getting about 6.8 GPH- this year I have been running it for longer periods at lower rpm (2K or below) and have averaged 3.7 GPH- one of the drawbacks of the higher rpm is the noise. The engine bay is insulated but I was going to ask this forum about what they have down for sound proofing. At 2400 as I said I get between 11.5 and 12.3 kts- I have pushed it to 2600 and am getting 15+ kts there but am sort of nervous about running it at WOT for very long- this is (for me) an interesting discussion and I appreciate all the comments and insights- I am also wondering whether I am propped correctly- (I do have my prop information but its on the boat)

 

[Mainship Pilot]

Noise is probably the biggest drawback of the 6LPA, it’s LOUD at cruise! When we cross to Catalina, 26 miles, it’s pretty much in silence between the admiral and I. Otherwise we would just be yelling!

 

[Duetto]

fwiw, we have run our yanmar 4jh3's at 3400 (3800 wot) for 20 years/4000 hrs. this is not on our mainship but a commentary on how you can run a diesel.