Mainship 40 general and 1 or 2 engines - Page 2

Dougcole · 05-18-2016, 06:50 PM

Hi Bigfoot.

Sorry for the delay getting back to you, I just noticed this post. At 2,900 RPM, about 15 knots, we burn 12 to 14 GPH. For cruise planning at fast speeds I figure on 1 MPG, just to give myself a cushion. At 1850 RPM, about 8 knots, we burn 4 to 4.5 gph.

On a recent three week trip we went from Stuart outside down almost to Ft. Lauderdale, then across to Bimini, then from Bimini to the Berrys, then messed around in the berrys for a while, then around Hole In the Wall into the Abacos, North throught the chain around to West End then back up to Stuart we burned exactly 10 GPH. That was a mix of hull speed and fast cruise. that also included a good bit of generator use.

Hope that helps.

Bigfoot4 · 05-19-2016, 10:03 AM

Thanks for the info Doug

adk1 · 05-19-2016, 12:10 PM

Quote:

Originally Posted by charlesr

Just joined the forum as my wife and I head toward retirement and a cruising lifestyle. Hoping you folks can provide sage advise. We looking at a 40-45' power boat that will be based in St. Pete's, FL

Our cruising style is 7-8 kts but I like knowing I have more speed available if necessary to avoid weather, etc. We'll probably spend about a week at a time on the boat, maybe a few weeks in the Bahamas or who knows, we might do The Loop some year. Usually it's just the two of us but will probably have guests for day trips or looking forward to welcoming new marina friends on board for a cocktail; ie entertaining space. We've bounced around a lot of styles but we keep coming back to trawlers and I'm seeing everything we need plus decent value in the Mainship 40 (opinions welcomed please).

What I'm really struggling with is single or twin engines. I see the advantages of each:
Single - better fuel economy (I assume), lower maintenance costs, more room to service the engine, etc
Twin - reliability of two engines, faster at WOT, better maneuverability (although bow thruster is standard on the singe, it seems lots of the twins have them as well)

My problem is I don't know which of these are significant advantages.
Sorry for the lengthy post but any insights or general comments on the Mainship 40 much appreciated

We seem to share common goals. I am already steering away from twins based upon fuel consumption, added weight and added cost to maintain etc. I totally agree on the bow and better yet, bow and stern thrusters. I have been seriously looking at the mainship lineup, I like the layout and the cost. I have heard though that they are really meant for inter coastal cruising etc and also do not track as well as others due to a smaller keel? I have also been looking at the tug lineup, between American, Nordic etc. Much more expensive than the Mainship but seem to be able to handle more water

Bigfoot4 · 05-19-2016, 01:23 PM

ADK1

We have owned ocean boats since 1981 with single gas, twin gas and twin diesel

Certainly a single diesel is most economical in most situations but our history is as follows

Single gas- carburetor problem- tow home
- seized up the clutch on a leg- tow home

Twin gas - v-drive breakdown- came home on twin engine
- distributor bearing failure- came home on twin engine
- irreparable water pump failure- came home on twin

Twin diesel - blew an o-ring at an oil cooler -came home on the twin engine
- lost an air sensor- came home on the twin engine
- lost a leg - came home on the twin engine
-lost a clutch on a leg- came home on the twin engine

The common denominator for the twins is "came home on the twin engine"

As we boat in an area that does not have a C-Tow or equivalent service or many boaters in the area to help out, "coming home on the twin engine" is extremely important.

I would never own another single engine boat and I would never fly to Europe in a single engine jet airplane.

An often used argument for single that commercial fishing boats often use singles but these guys are often within sight of other vessels and help.
If you are in the same boat, then a single engine might be the way to go but ruling them out for money saved and giving up safety needs careful consideration.

Dougcole · 05-19-2016, 09:05 PM

Without getting into the general advantages/disadvantages of twins vs. single I'll speak to the specific reasons I think a twin Mainship 400 is a better boat than a single, at least for me.

1. Speed. The twin is capable of cruising at 15 knots at about 75 to 80% throttle. The single, from everything I read, is not.

2. Fuel burn. The twin burns only marginally more fuel at all speeds, and less at over 10 knots.

3. Draft. The draft on the single is around 6" more. That may not matter in some parts of the country but it matters in the Bahamas and Florida.

4. Engine access. Some on here are going to howl about this, but due to the layout of the ER Hatches, engine access on the 400T is the same as, if not better, on the twin. You open one hatch and you are down between the engines without moving any furniture. To access the port side of the engine on the single you have to move the couch.

5. Resale value. The twin engine boats are worth in the range of $10,000 more on the used market, and according to my broker, sell faster.

Again, there are advantages for twins in every boat (maneuverability, get home ability) and disadvantages (maintenance costs, unprotected props) but these are specific to the 400.

adk1 · 05-19-2016, 09:20 PM

Very interesting that a twin drafts less than a single? Good comments on this post they are appreciated. The safety aspect of a backup engine has me thinking more. I guess depends on the type of cruising. I look at the nordhavn three at sea who have cruised thousands of miles with only a single in their 40'. Were they just lucky? Hard saying.

ranger58sb · 05-20-2016, 07:31 AM

Quote:

Originally Posted by Dougcole

4. Engine access. Some on here are going to howl about this, but due to the layout of the ER Hatches, engine access on the 400T is the same as, if not better, on the twin. You open one hatch and you are down between the engines without moving any furniture. To access the port side of the engine on the single you have to move the couch.

Do the engines have service points on the outboard sides? What does it take to access outboard sides of each engine in the twin set-up?

-Chris

Dougcole · 05-20-2016, 08:16 PM

Yes, there are service points on the "outside of the engines." I'd call the access to that area fair but not great. Main thing is a few zincs, which are pretty easy, the raw water pump and impeller on the port side (you have to pull the pump, but you have to do that anyway to access the impeller) and the oil filter on the Stb side which I change by punching a hole in it and draining it into a milk jug.

Hydrophilic · 05-22-2016, 07:37 AM

One other advantage of the single is that the prop is better protected from floating debris. I looked at both and bought a single. One year later, I am happy with that decision. I suggest that if going fast is a major desire, you might consider a different type of boat that can get to 20 - 30 knots

IntoTheBlue · 05-22-2016, 08:45 AM

I had owned a Mainship 390, with a single Yanmar 315. Cruising speed was 8-10 knots. This is similar to the 400. I'm not sure if you can get a 400 with a 315, as I recall Mainship changed their focus to fast trawlers. I would recommend the 390 as a possible alternative (if you want a real trawler speed boat).

ranger58sb · 05-22-2016, 09:12 AM

Quote:

Originally Posted by Dougcole

4. Engine access. Some on here are going to howl about this, but due to the layout of the ER Hatches, engine access on the 400T is the same as, if not better, on the twin. You open one hatch and you are down between the engines without moving any furniture. To access the port side of the engine on the single you have to move the couch.

Quote:

Originally Posted by ranger42c

Do the engines have service points on the outboard sides? What does it take to access outboard sides of each engine in the twin set-up?

Quote:

Originally Posted by Dougcole

Yes, there are service points on the "outside of the engines." I'd call the access to that area fair but not great. Main thing is a few zincs, which are pretty easy, the raw water pump and impeller on the port side (you have to pull the pump, but you have to do that anyway to access the impeller) and the oil filter on the Stb side which I change by punching a hole in it and draining it into a milk jug.

Aside from the couch things, which sounds like it an issue in both configurations...

I'd have thought all that outboard work on the twins version would mean all-round engine access on the single is better...

-Chris

Dougcole · 05-22-2016, 11:18 AM

I don't think I did a good job of explaining the layout.

There are three hatches in the main salon floor. A big one in the center and two much narrower hatches on each side of it. If you open the single large hatch in the center with twins you step down in between the engines, there is lots of space there. If you open the center hatch with a single, the engine is directly below you, and I don't think (I could be wrong) you can slide in around it without lifting the side hatches. The port side hatch is under the couch (or chairs in some boats).

I seldom open the side hatches, I just go through the main hatch and climb around either forward or aft of the engines. There is room to sit in front of either engine, and decent space behind them, though the shafts/trannys are in the way.

As far as the speed thing goes, as I said in my first post I don't want to rehash the old single vs. twins argument in general. But a 20 to 30 knot boat is an entirely different animal than a 15 knot boat. They come with different issues costs etc.

Coming from our old Gulfstar, we wanted a boat that could comfortably run at least 15 knots when needed. I wasn't remotely interested in sea rays or other Euro styled type boats. We looked at a few sportfish, but didn't like the layouts. I like to fish, but that is not the primary purpose of this boat.

The Mainship 400 with twins checked all of our boxes. Quite simply, the single did not.

Other than slightly higher costs I see no disadvantage in having a boat that is capable of running economically at 7 to 8 knots when desired but can also run close to twice that speed when needed.

Again, I'm not speaking of every boat. But in the Mainship 400, the twin is a better boat, there really isn't a logical argument otherwise.

ranger58sb · 05-23-2016, 06:24 AM

Quote:

Originally Posted by Dougcole

I don't think I did a good job of explaining the layout.

There are three hatches in the main salon floor. A big one in the center and two much narrower hatches on each side of it. If you open the single large hatch in the center with twins you step down in between the engines, there is lots of space there. If you open the center hatch with a single, the engine is directly below you, and I don't think (I could be wrong) you can slide in around it without lifting the side hatches. The port side hatch is under the couch (or chairs in some boats).

Ah. Three hatches, yep that's good clarification.

-Chris

Mainship400 · 07-10-2016, 09:38 AM

I had the single engine 400T (just sold it). We opened the large center hatch and the starboard hatch to access the engine. You could get to the port side with a little bilge yoga. My next boat will probably have twin engines for all the reasons that Doug stated.

IntoTheBlue · 07-12-2016, 06:42 AM

Quote:

Originally Posted by Mainship400

I had the single engine 400T (just sold it). We opened the large center hatch and the starboard hatch to access the engine. You could get to the port side with a little bilge yoga. My next boat will probably have twin engines for all the reasons that Doug stated.

We just met a couple in Yarmouth who traveled 5,000 miles on their Mainship 43 Aftcabin. The boat had twin Cummins 330 and cruised at about 12 knots, capable of 16 knot speeds. I have the same hull, pilot version and run cruising speeds of 15-16 knots, capable of 22 knots with twin Yanmar 440's. I bring this up because if your going with twins, but still want to cruise at 10 knots, make sure that the twins are lower HP engines. Diesels need to run at 75-80 % power at cruising speeds. Running all the time at 50 % is not good for the motors, especially if they have have turbos. (Always heard this, but had it confirmed at Mack Borings diesel 2 day seminar). So you have to power your boat accordingly or if buying used, make sure that the power meets your desired cruising speeds.

smitty477 · 07-12-2016, 07:44 AM

"Diesels need to run at 75-80 % power at cruising speeds. Running all the time at 50 % is not good for the motors, especially if they have have turbos. (Always heard this, but had it confirmed at Mack Borings diesel 2 day seminar"

As long as the boat is propped correctly running most any turbo diesel at 50% will be fine and even preferred.

IntoTheBlue · 07-12-2016, 08:37 PM

Like I said, I've heard it, read it and when attending a 2 day seminar at Mac Boring had it confirmed by Larry Berlin. To say it may be OK to run at 50% maybe one thing. To say it is preferred is against all accepted criteria regarding diesel cruising speed. I don't agree with smitty447. Maybe the 50% theory works with gas motors.

smitty477 · 07-12-2016, 08:47 PM

"To say it is preferred is against all accepted criteria regarding diesel cruising speed. I don't agree with smitty447."

If you would really like some good feedback go to boatdiesel(dot)com and ask this same question.
Or you can go to Tony Athens site or call him up and ask his real world experiences with engines of this type at sbmar(dot)com.
Or just go to the sbmar site and read "Tony's tips" for some good background.
Its been 25+ years that I have run similar sized 6 cyl 4stroke diesels with plenty of feedback from similar owners with all good results.

Cruised long Island waters for many years now likely have been out there on the water with you at some point.

jann · 07-23-2016, 05:28 AM

I have a twin engine 34 mainship trawler. and I'm so glad I got a twin.

Three times in the last 2 years I needed the extra motor to get back home.

due to 1)crap trap line, 2)impeller down, 3)raw water line broke.

I really don't understand the single engine argument... to me it's a no brainer.

Mainship400 · 07-23-2016, 04:26 PM

Quote:

Originally Posted by jann

I have a twin engine 34 mainship trawler. and I'm so glad I got a twin.

Three times in the last 2 years I needed the extra motor to get back home.

due to 1)crap trap line, 2)impeller down, 3)raw water line broke.

I really don't understand the single engine argument... to me it's a no brainer.

Jann, curious about how good the engine access is in the 34 twin? The single looks pretty tight to me. Can you get at both the water pumps? All the Zincs?
Thanks
John