Pre-2003 Mainship Pilot Performance

[Seadweller]

Pre-2003 Mainship Pilot 30 Performance

If I'm correct, Mainship added a tunnel to the Pilot in '03, so my question is related to pre-'03 models.

With the Yanmar 4LHA-STE powerplant, at what speed does the hull truly get "on plane"?

 

[DavidM]

I presume you are talking about the Pilot 30, not the 34? I think only the 30 came with a single Yanmar 4LH engine.

David

 

[Seadweller]

I presume you are talking about the Pilot 30, not the 34? I think only the 30 came with a single Yanmar 4LH engine.

David

Yes, apologies, I thought I had put that in the title...I've corrected it!

 

[tego]

My son has a 2000 34' MS pilot with the single Yanmar. He's on the MS Facebook group quite often. His home port is St Joseph, MI. He checks in here every so often but doesn't post here much ("Tinpusher"). I'll ask him to comment when I see him tomorrow night in Annapolis. (I know they cancelled the show but we're going anyway for the seafood- tough to get good crabs and oysters here in Tennessee). Ben

 

[Seadweller]

My son has a 2000 34' MS pilot with the single Yanmar. He's on the MS Facebook group quite often. His home port is St Joseph, MI. He checks in here every so often but doesn't post here much ("Tinpusher"). I'll ask him to comment when I see him tomorrow night in Annapolis. (I know they cancelled the show but we're going anyway for the seafood- tough to get good crabs and oysters here in Tennessee). Ben

Thanks...Ah, Tennessee. Spent a good amount of time in Johnson City.

 

[caltexflanc]

We used to day charter a 1999-ish 30 with a single Yanmar, out of Alameda on San Francisco Bay. It didn't plane. The sister boat with a Cummins did, kind of. They seemed to be 8 knot kind of boats. Fun though. The 34 with a single Cummins out of Sausalito did plane, and we used it for some longer journeys, like day trips up to Napa or Petaluma. Owners may have more thorough info, but that's my recollection, now 17 or 18 years dated.

 

[Seadweller]

We used to day charter a 1999-ish 30 with a single Yanmar, out of Alameda on San Francisco Bay. It didn't plane. The sister boat with a Cummins did, kind of. They seemed to be 8 knot kind of boats. Fun though. The 34 with a single Cummins out of Sausalito did plane, and we used it for some longer journeys, like day trips up to Napa or Petaluma. Owners may have more thorough info, but that's my recollection, now 17 or 18 years dated.

That's what I'm worried about. The owner claims 13kts @ 2900rpm's. I can tolerate 13kts, but not 8kts or below.

 

[DavidM]

That's what I'm worried about. The owner claims 13kts @ 2900rpm's. I can tolerate 13kts, but not 8kts or below.

I don't think it will make those numbers. The newer model with the 315 hp Yanmar could but not the 220 hp Yanmar.

And anything less that 13 kts, say 10-11 puts you climbing over the hump which is extra load on the engine so not good. As others have said, 8 kts is about right for that engine.

David

 

[Seadweller]

Thanks...This is what the owner has recorded:

 

[Seadweller]

By the way, the last survey report from 2019 indicates a cruise RPM/speed of 3000/12.7kts, and a WOT RPM/speed of 3426/15.8kts.

Is this particular hull fully on plane at 12.7kts?

 

[DavidM]

That chart is a little suspect in that the maximum fuel flow of that engine is about 14.5 gph not the 16.2 shown on the owner's chart. The data sheet is attached.

But why don't you specify in the purchase contract that if the boat doesn't make 13 kts at 2,900 rpm that in addition to returning your deposit and cancelling the contract (standard terms in most purchase contracts) he will pay for the haul out and surveyor's cost? Make him put his money where his mouth is if that speed is all important to you.

David

 

[Seadweller]

Make him put his money where his mouth is if that speed is all important to you.David

It's not so much that a particular speed is important, but more so if the boat can run comfortably on plane at a reasonable RPM that maximizes fuel consumption. If the hull is designed to fully plane at 12kts without tabs at 2800rpm for example, that's fine. I just don't want to get in a position where I'm either running 7kts, or pushing a wall of water at anything but WOT.

 

[willpep]

I owned a MS30 with a Cummins 6BT 220hp for 10 years or so. 2650rpm WOT recorded 17kts. Normal cruise for me was 2400 at 14 kts. At 2300 was a very enjoyable 13knts. Currents made a +/- 2 knot difference in LIS. Trim tabs about +1 knot.

Every season I would calculate avg gal/hour and it was usually 6-7gph. Note I live 4 miles from LIS and run at low rpm until I get into open water. That skews the GPH numbers down a bit.

Cheers Will

 

[Tinpusher]

Not sure if the actual answer has been found for you in this thread. But to the point of the Pilot 30 and 34 with singles:
As my dad (tego) mentioned, I have a 2000 34 Pilot with a single Yanmar. It will get on step at around 16 or 17, then I can back her down to around 12 before she starts to fall off again. I routinely run 15 on Lake Michigan on step at 2600rpm.

 

[Seadweller]

Thanks everyone! I have to say, I'm still confused by all of the data. I found a test report online (230HP Yanmar) that indicates performance that would be perfect for my use. Just not sure how realistic the data is. If the boat performed at 2600RPM as indicated below, I'd be thrilled. I just don't understand why there's such a wide variance.

"We tested the boat with three passengers, full fuel tank, half-full water
and light gear in over 60 feet of water in a 1-foot chop. Range is calculated based on 90 percent of fuel capacity".

RPM KNOTS GPH NMPG RANGE dBA(sound) TRIM
1000 5.2 0.4 13 2041 67 1
1500 7.7 1.81 4.3 668 69 2
2000 8.7 3.42 2.5 399 71 3
2200 9.5 4.16 2.3 359 73 3
2600 13.1 5.69 2.3 361 81 4
3000 16.8 7.82 2.1 337 83 4
3400 19.4 10.57 1.8 288 84 4
3500 20.5 11.58 1.8 278 85 4