1997 Mainship 37 MY

[varkpilot]

Originally Posted by TooCoys

I would LOVE a Chris Craft Commander, but they seem to all be much older models. Most of the ones that I've seen listings on have been 60's, 70's, and early 80's models. I'd be concerned with much more on an older vessel than just the engines.

Ahh. Good for you. The Commanders were among the first glass boats that Chris Craft built. And man, were they built! Even now, they have the reputation of being an almost bullet-proof hull, and all the surveys I've seen on them recently have come back clean as a pin, old as the boats are. You can pick up a 41 or 410 (newer) Commander for 25,000 with gas engines. Pay particular attention to the number hours on the gas engines. At around 1,500 hours they sometimes start nickeling and dimeing you pretty hard. Just depends on how the previous owner(s) treated them. Finding them with engines that have been replaced or overhauled is NOT difficult at all. There is a website called the Chris Craft Commander Club, free to join and has some very good information on there. I joined several months ago. If you like the Commanders, try PopYachts. They've been very helpful in helping me with my search. BTW, I have no affiliation with them or anyone else. I'm nothing but an old, retired Air Force fighter pilot. Again, if you need help with anything, I'm not busy at much except keeping my Kindle recharged. :-)

[varkpilot]

Originally Posted by SV Bacchus

Sailing Miss Lone Star, on Youtube, took their Cruiser from Kemah around the coast and down to Key West then up to Islamorada. Twin 454's, melted their credit cards! They would burn 300 gallons in a day.

Now on a sail boat..

Oh, and as mentioned (although not as graphically) gas explodes.

Hi, Bacchus. Yes, gas is explosive. That's why God invented the sniffers and bilge blowers. They actually work! :-) And on the other hand, diesel burns, too. Only a little harder to get it started burning. Just takes a little carelessness, just like gas. Wish I was still able to handle a sailing rig. I once owned a 65' schooner and loved the thing. An old wooden boat and you had to have a small crew to sail the thing. What a blast! But that was many, many moons ago.

[TooCoys]

Originally Posted by SV Bacchus

Sailing Miss Lone Star, on Youtube, took their Cruiser from Kemah around the coast and down to Key West then up to Islamorada. Twin 454's, melted their credit cards! They would burn 300 gallons in a day.

Now on a sail boat..

Oh, and as mentioned (although not as graphically) gas explodes.

I started watching them when they first started, but found them highly irritating. I haven't watched an episode after their 2nd or 3rd when she started explaining sex on the boat with kids.

[ranger58sb]

A '97 Mainship MY would have been produced in between their earlier and then later "trawler" years. Some innovative layout features, but in general: pretty good Chevies, in the grand scheme of that kind of boating. Compare to Silvertons (a sister company, at the time), Carver, Sea Ray, Cruisers etc etc etc etc.


(Really. Go to yachtworld and compare. Slightly larger boats may offer features you like even more, and often maybe also diesels at not much more money, or at least at "affordable more" money. $118K for a '97 37' Mainship with gas engines is ridiculous. Even $50K for that particular boat may not be a great deal. Also, go to trawlerforum.com -- as sister forum -- and look for user "timjet" who has just announced he's selling his... hmmm... Carver, I think, approx. 36', aft-cabin motor yacht, with twin diesels, competitive price with your friend's Mainship.)


Gas engines have their well-suited place in the boating hierarchy. Generally they're best for shorter or more occasional trips, and of course they excel as dock queens. The cost of diesels for these roles often is too intimidating... so they live at the other end of the spectrum... along with a heftier up-front cost. Even then, for longer or more frequent, it's often a simple question of "Do I pay a lot upfront now (diesels) or die a thousand deaths over time (gas)?"


Repowering that boat with diesels would cost somewhere between $40-70K (and remember the genset, too)... and if the boat is worth $40K when you start, it'll be worth $42K when you finish.


Maintaining gas engines can be (conceptually) no more expensive than maintaining your car engines... except that boat will have two of them. Still, not a big deal. If they really crap out, repowering with newer more modern gas engines wouldn't cost an arm and a leg... well, maybe only a leg, but much more doable that repowering with diesel.


If you run that gas boat at "trawler-like" speeds, i.e., about 1 kt below theoretical maximum hull speed, you can make long distances relatively cheaply. Sometimes sea states don't cooperate, but if you watch your weather, all that is very manageable.


-Chris

[TooCoys]

Originally Posted by ranger42c

If you run that gas boat at "trawler-like" speeds, i.e., about 1 kt below theoretical maximum hull speed, you can make long distances relatively cheaply. Sometimes sea states don't cooperate, but if you watch your weather, all that is very manageable.


-Chris

What is maximum hull speed?

Is that the maximum speed you can go before you start plowing through the water before planing?

I'm assuming that because this is a modified V hull its more l like a planing hull than a trawler right?

[Three Sisters]

Originally Posted by TooCoys

What is maximum hull speed?

Is that the maximum speed you can go before you start plowing through the water before planing?

I'm assuming that because this is a modified V hull its more l like a planing hull than a trawler right?

The 454 cubic inch engine was available in several flavors for marine use in 1997. Carbureted and MPI being multiport fuel injection, and finally EFI (electronic fuel injection). MPI and EFI injection will involve several electronic components. Each fuel delivery system will have differing benefits and Gallons per Hour consumption.

[varkpilot]

Originally Posted by TooCoys

What is maximum hull speed?

Is that the maximum speed you can go before you start plowing through the water before planing?

I'm assuming that because this is a modified V hull its more l like a planing hull than a trawler right?

TooCoys, if I understand correctly, there is a formula for finding the hull speed of boats. I think you'd be safe to say that the moment before you provide enough power to get on the step, or plane, would be the hull speed (close enough for government work). In the Commander (the only one I know about for sure) that's around 12 knots. So yes, you are exactly right.

The true trawler is definitely a displacement hull and doesn't plane. Neither does an aircraft carrier, which is also a displacement hull. The modified V is often designed with "steps" to allow the hull to plane. The Mainship and Commander have this design and are capable of speeds fast enough to ski behind. You're going to get about 1 mile per gallon for fuel consumption while planing. If there's a chop to the water, the ride will also be rougher. If you stay below planing speeds, your passengers and credit cards will thank you. 11 knots is a good number, so long as you're not in a hurry.

[ranger58sb]

Originally Posted by TooCoys

What is maximum hull speed?

Is that the maximum speed you can go before you start plowing through the water before planing?

I'm assuming that because this is a modified V hull its more l like a planing hull than a trawler right?

Yes, ref "before plowing." For a true displacement hull, the formula would be 1.34 * SQL(LWL), so for that boat, someplace around 8 kts. That is NOT the most efficient speed for fuel economy; usually that would be more like 1.0 * SQL(LWL) so more like 6 kts for that boat. And that's all theoretical, isn't perfectly exact for a planing hull (but close enou8gh for conceptual discussion), etc...

But it's also true that with a planing hull and inboard engines on a boat that size, you mostly burn more fuel/hour as RPMs increase without regard to speed... so your most economical speed would probably be around 6 kts and it goes downhill from there. (There are exceptions, especially light, fast boats powered by new outboards at serious speeds.)

-Chris

[tkeithlu]

Theoretical hull speed in a monohull is 1.34 times the square root of the waterline length in feet, answer in knots. That's the last point at which the transom is supported by the second wave. Thereafter you are climbing the bow wave, bow up, also called "plowing." Huge wake, huge fuel expense. For a 36 ft waterline, 1.34*6=8 knots. Generally speaking, better fuel economy is found a bit below that speed. Our theoretical hull speed is 8.7 knots, but we cruise at 7.6 or so.

[a64pilot]

We had a 36 Sportfishing boat with twin Merc 454's, carburated but with electronic ignition.
We had flowscan fuel flow meters and I graphed fuel burn and speed. What I found was the best fuel mileage was at idle, any above that and fuel mileage came down, graph got real steep at about hull speed. And sort of flattened a bit once on plane, but graph increased with speed, was steeper at some points, but there was no speed that gave best fuel mileage.
This disappointed me greatly cause I was certain that the point just where I could keep her on plane would be best mileage as you have to hold it wide open to get her to break over on plane, but once there you back off, a lot.
I believe those engines actually ran at different rotations, one spun clockwise, the other anti clockwise if I remember correctly.
Easy to work on and truth be know required not all that much maintenance, but I'm a gear head too.
But fuel consumption was phenomenal, a weekends fishing hard was hundreds of gallons of fuel, hundreds.


Sent from my iPad Pro using Cruisers Sailing Forum

[TooCoys]

Originally Posted by a64pilot

We had a 36 Sportfishing boat with twin Merc 454's, carburated but with electronic ignition.
We had flowscan fuel flow meters and I graphed fuel burn and speed. What I found was the best fuel mileage was at idle, any above that and fuel mileage came down, graph got real steep at about hull speed. And sort of flattened a bit once on plane, but graph increased with speed, was steeper at some points, but there was no speed that gave best fuel mileage.
This disappointed me greatly cause I was certain that the point just where I could keep her on plane would be best mileage as you have to hold it wide open to get her to break over on plane, but once there you back off, a lot.
I believe those engines actually ran at different rotations, one spun clockwise, the other anti clockwise if I remember correctly.
Easy to work on and truth be know required not all that much maintenance, but I'm a gear head too.
But fuel consumption was phenomenal, a weekends fishing hard was hundreds of gallons of fuel, hundreds.


Sent from my iPad Pro using Cruisers Sailing Forum

My little 4.6L Volvo Penta in my Chaparral is like that. Its only 18.5', but I have to hammer down to get it out of the hole. It's only a few seconds, and once it breaks plane, its GONE!

I just really want to be able to cruise to other local areas.

And I was thinking last night that if we were to drive down to Port Aransas and stay for a few nights, we'd end up paying $150 a night for a hotel room. So just a few nights stay in a hotel could easily equal the amount of fuel we'd spend. Its just that this way we're bringing our own hotel room.

[smac999]

keep in mind the saftey issue between gas and diesel. I don't know if I'd live aboard a gas boat.

[TooCoys]

Originally Posted by smac999

keep in mind the saftey issue between gas and diesel. I don't know if I'd live aboard a gas boat.

Diesel burns, gas burns, propane burns, natural gas burns.... You're probably more likely to wreck the boat than you are to blow up in one.

It's all safety measures. We live full time in our RV now and we have to be aware of propane. So we always double check our lines, turn things off when we leave, and make sure our warning sensors are running.

[Three Sisters]

[ranger58sb]

Originally Posted by TooCoys

I just really want to be able to cruise to other local areas.

And I was thinking last night that if we were to drive down to Port Aransas and stay for a few nights, we'd end up paying $150 a night for a hotel room. So just a few nights stay in a hotel could easily equal the amount of fuel we'd spend. Its just that this way we're bringing our own hotel room.

Yep, lots good to be said for gas in that kind of a role. Pay attention to safety issues, of course, but all that is very manageable.

Even for the once/year or once/every X years looooong trip, fuel costs can be manageable in various ways. Not the same as zooming out to the canyons every weekend for tuna or whatever, but as a potential mobile liveaboard (or moveable hotel room, or condo), could work within a decent budget if you pay attention.


That particular boat? Maybe, maybe not. Depends on comparables, depends on whether it really has all the features you need/want/like, depends on whether the (eventual) price is competitive in the marketplace, etc. And it depends on whether you love it...

-Chris