Moesly Seacraft 21 repower opinions
 

First of all, I hope y'all on the eastern seaboard survived Matthew with minimal damage. My sister is in JAX and faired pretty well. On the other hand, some friends in Lumberton NC took a beating and are about to lose a dam/levee. God Bless you all.

I'm thinking about re-powering my 21 Moesly for Christmas. Unfortunately, like the Kinks, circa 1979, i'm on a low budget, thus I'm looking for your .02. I took the liberty of dragging sme of Fr. Franks quote over from the earlier I-6 discussion to start an opinion gathering thread for repowering a 21.

Ive been looking for a solid I-6 MC 165, but I think I'd like more top end than 165 can offer and also a fairly efficient cruise ant troll. In that earlier thread, FLexpat mentioned the 292/200 hp set up from FirstMate which sounds appealing. Not sure if the extra 35 ponies gets me much but I'd like to get to 35-40 mph in flat water. In fact its 50 more ponies than right now, as i have a 50 year old 150 mercruiser.

Logic says follow IslandTrader's lead and put a small block gm in there, but I like the idea of keeping the layout original an doing little more than painting the engine cover. using something like 3rdDay's choice of a 400 pound 200 hp on a bracket is also a possibility, I guess. Can you say used 2.6 L Etec? Sure...

The thought of getting 200 ponies or better from an I-6 is appealing.

I welcome all thoughts se please, feel free to chime in.

You asked for our .02--- how about the 292 you mentioned.Clifford research four barrel intake. get with Holley and I'd bet they could set you up with a throttle body fuel injection system then upgrade to a electronic ignition system and I wouldn't think mercury' 250 hp number would be hard to achieve .you could get with Clifford and see if a cam is needed to match what Mercury was using ?

The Clifford intake won't fit with a marine exhaust manifold but I think the original intake was set up for a small 4bbl on some of them. That said since a 292 is 4.8l it probably only flows about 350 cfm, a 4bbl is probably a waste of fuel - the more modern marine 2bbl from a 5.0 will flow about the right amount of air and be a bit more efficient - it might fit the existing intake. I would worry about reversion of water if the cam got too 'hi performance' or someone did not understand the difference between a marine cam and a performance cam - maybe work the head to make it higher flow/more efficient instead? Crowley will do custom cam grinds and match it with roller lifters but I don't know if they know what the marine cam is. A rebuilt mercruiser long block with marine cam is 2200 from Perfomance Pro (reselling for FirstMate).

Thanks, wattaway. I am very intrigued by the gm 292 idea. What about the sterndrive? Any insight on compatibility? My understanding was Merc only mated it to a Mercruiser II. Do you know of requirements to to make it adaptable to more current drives like Alpha, Bravo, SEI? Simple as a transom plate and gimbal housing? Would it require a particular gear ratio? I'm very excited to learn more.:cool:

Hey Gillie,

What sort of WOT are you getting with the 150? Don't know what Bob Reiland's WOT was with the original 150 MC in the Moesly 21 "Unohu", but once he learned about the importance of using a vacuum gage and observing a limit of 5-7" Hg for max continuous/cruise power for decent exhaust valve life, he was limited to cruise speeds of about 18 kts. However Bob's friends said he ALWAYS ran 18 knots back then, regardless of sea conditions, so he kinda liked it when seas got up to around 4-6', when few other boats could stay up with him! The last engine he had in it was a 290 hp/350 Chevy/Volvo outdrive, and he said it was a 50 mph rig, although it was also thirstier than the 260 MC! Too bad he passed away a few months ago, as I'm sure he could give you some good advice on how much power you need to get the speed you want! You might also send a PM to Carla, as I'm sure Carl would know that answer!

There's no substitute for cubic inches, so I'd do some research on that 292 block and the Clifford Research site! Is there any way to install the OHC Pontiac head on the 292? With an aluminum head, you'd have to add FWC, so not sure if it would be worth the extra complexity. It's easy to soup up an engine with a hot cam and bigger carb, but doing that usually trades mid-range torque for high end HP and a rough idle, so not always what you want for marine use. A V-8 would certainly meet your WOT speed goals, but a well built 292 (ported head with a good 3 angle valve job and possibly oversize valves, Stellite valve seats, positive valve rotators, and file-fit rings for min gap/leakdown) might develop a surprising amount of HP while still making for a simple installation and easy maintenance. Only question would be how the cost of that would compare to a stock V-8 + boat mods. I suspect the V-8 might actually be a cheaper and simpler route if you could do the boat mods yourself.

Besides cylinder head airflow capacity, the camshaft is the key item for making power. If they make roller cams for that motor, that allows you to open the valves quicker with more lift for more "area under the curve" and more airflow/power without going too wild on duration that would screw up mid-range torque and idle quality. This would be a marine/RV type cam grind as opposed to a race grind that's often used on roller cams. It might also require solid lifters, so you'd also have to be willing to adjust valve lash occasionally, but that's not too hard once you learn to do it. Fuel injection really won't add any power relative to a properly set up carb. It might improve starting and idle operation, but it will require more sensors and be much harder to set up. I think a mildly "breathed on" I-6 and a more modern Alpha drive would be a unique and easily maintained set-up that could offer surprising performance if done right! Keep us posted on what you find out! Denny

Thanks Denny, I really appreciate the insight. WOT feels like 30 mph or less at 3900 rpm... Original tach, so sketchy at best. Seafari quickly does 36 mph and that feeling of speed is there. That nimble quickness is not there in the 21. Of course it's a lot heftier and I really haven't spent the time or effort to dial it in. The seafari is dialed in with a solid 115 tower, goes w/o saying. very different animals.

I'm not really wanting to hop it up just seeking I6 reliability and a sense of giddy up if necessary. I'd love to see 40mph or so cuz the hull deserves it, but I don't think I'd be inclined to spend a big wad of cash on a hot cam or carb to gain 2-3 knots on top end. Most of the time I would be cruising 15-20 knots or less searching for fish offshore.

I want consistent and absolute control @ low idle for trolling and docking and the inherent low and midrange torque of the I6 on plane. I want to preserve Carl's balance fore and aft, and to keep the original engine cover. I really like the original layout, although truth is l really lack Brian and Terry's discipline and motivation skills to do fantastic restorations like theirs. :o

You may be over propped if the tach is accurate (if you could find a strobe light type tach, that would be a good way to check it), as I'd think you should be turning at least 4500, so a larger dia prop with less pitch might spin faster and give you a better hole shot with about the same top end. Bob used to easily cruise at 20 kts at about 9" vacuum with a Bahamas load with the 260 hp MC, which was perfect for following him in my Seafari with the 115 on it, although I had to wind it up to 4500 to stay with him. I'm sure he could have cruised at 25-28 kts if he wanted to. Might touch base with Island Trader to see how much you'd have to mod the deck and engine box to install a V-8. The Chevy V-8's are so common that you can almost buy parts at the corner drug store, so it may actually be cheaper to run a stock V-8 than trying to find an I-6 that's been out of production for years. The weight difference/balance shouldn't be much different.

Data from Carla's website indicates that the 21 would run 40 mph with a 225 hp MC. I'm guessing that was probably a 327 cu. in. V-8.

Did a lil research as you got my curiosity up --don think the intake will work do to the wet exhaust manifolds . Looked at Barrs site and looks like the manifold has the intake and exhaust combine dint one unit . It does look like a carb adapter is used that might allow for use of the Holley 2bbl throttle body injection . A buddy used there(small 650 cfm unit ) on a healthy 360 mopar greatly improving his idle speed and fuel economy and overall performance . They make a "lump" to install in the cylinder heads intake ports to improve the air flow redirecting the air for a better angle approaching the valve I found very interesting

What would you anticipate the performance with a 300hp outboard or twin 200 outboards?

Good luck with the re-power.....

Since the door was left open a crack on outboards I was thinking how sweet it would be to go old-school Merc twin towers like many of the classic racing 21's. I see from some of the original literature the 21's were offered with twin 100's or 115's. Sorry no tech but it's nice to imagine.

I think outboards would be a LOT more expensive than staying with an I/O. If they were mounted on transom, balance would probably be ok although shifted aft a bit relative to the I/O, but cutting the transom to mount outboards and building a splashwell would also be BIG job and not retain the configuration Gillie likes.

Would not recommend a bracketed outboard like Brian used, as it would significantly change balance of the boat. In addition to adding the bracket, he also removed the windshield and big fiberglass seats up front to install a CC, further increasing the aft CG shift. One of the video's he posted of the boat running in a light chop showed some porpoising which the stock boat NEVER did. The bow on the stock configuration Unohu and Island Trader's 21 hardly bounced at all in 2-3' seas, so I've concluded that those mods adversely affected the balance and ride of the boat. I think Gillie is on the right track in staying with the I/O. Only question is whether a modified I-6 or stock V-8 is the most cost effective route.

I agree with all you said. Just a thought exercise based in nostalgia and vanity.

Thanks Bush,

I agree the outboard conversion would be more work and likely more expense. I was just wondering from a performance standpoint. The SC 21Ms are so rare.

I have read ITs thread but dont remember seeing any performance numbers on his (or Brian's for that matter).

I don't think (and I may be way wrong) that the SC 21M was every considered a speed demon, but that it could maintain higher speed in rough ocean conditions.

Sandlapper,
I had a Seavette with twin 2.4 l merc 200 with 225 carbs on transom. Previous owner got 68mph on radar gun. I would guess 60-65 would be a possibility with a pair of light ones.


SSPBill,
I concur a pair of 300 lbs 115s towers would be cool. But I'm looking for range and economy.
Skip and Carla are putting twin Etec 115s on outer strakes on their 21. That will provede added stability and allow them to frolic in the shallows around the keys. The hull will plane with a single 115.

Go Outboard.........a lot less maintenance

Evinrude etec G1 200 HO, or if rated for more, go with the 250HO.
Evinrude got the etec correct right out of the box......1st year 2005.
I have one from that year and it's been perfect since.
Highly refined outboard...........starts immediately warm or cold and go..........very quiet too.

Hi McGillicudy,

That is really impressive! A hull that planes that slow on so little power, with the ability to maintain speed in rough conditions but can still hit 60-65 conditions permitting. It sucks there are so few around....

I think I read that the Formula 233 gets very squirrelly above 50 unless a lot of work is done to remove the hook. Even then I don't think it is as efficient, or can handle the conditions your 21 can.

While I can't wait to start renovation on my project 23, I am scared my heart will never be true to her and will always be looking for a 21...

ETA: Sorry for the derail....

Bgreene,
Yeah outboards are sweet. I do like the etec 2.6 L for this ride but I don't think I have the funds or motivation to cut the transom and hang one. If the boat were more beat up, I'd probably give it a more serious look. Not off the table as I just came across some 2011 200's with around 400 hrs for $6500.

Sandlapper,
Appreciation of other boats is a passtime. Your 23 is a great boat, and in fact my first interest in Seacraft was spawned by a 23 Sceptre. I couldn't afford that one at the time, but I bought the first 20 Seafari I saw shortly thereafter. Eventually bought a Seavette, just to save it from the dump. Only sold it because I didn't have the heart to alter it, and the 21 was on its way.

Good luck with your 23 project!:cool:

Merc did a bunch of tests at Lake X back in the 60's and found that the VDH hull was about 10% faster than a conventional constant deadrise deep V of the same weight and horsepower, so the early SeaCrafts had a reputation for being pretty fast boats. What is really amazing is that all of the Moesly designs, if powered with the engines they were designed for, seem to be able to plane at about 12 mph! Don't think a similar vintage Formula, Bertram or Donzi will even come close to that!

I spent a lot of time under the 20' hull when I painted the bottom on my boat, and discovered some subtle details that show how brilliant Moesly was as a hull designer, despite no formal training as a naval architect:
1. The outer panel has a slight wedge built into it in the aft 10', which you can see if you sight along the chine back toward the transom. This helps the boat get on plane at low speed.
2. Since the hull develops more lift as speed increases, the hull rides higher in the water at high speed, so the outer panels are almost completely out of the water at about 40 mph. This means that the wedge built into the outer panels does NOT limit max speed as it would on a constant deadrise design.
3. Since the inner panel is carrying most of the load at high speed, Moesly incorporated a little bit of rocker into the inner panels, which allows the bow to rise at high speed to reduce wetted surface for less drag and more speed! If you look at the Boating Magazine test of the 20' Seafari in the Literature section, you'll see that sure enough, the running angle increases from a very flat 0.5 degrees at 32-36 mph to 1.25 degrees at almost 40 mph! I've noticed this in my own boat and think it's an absolutely brilliant design detail that very few people are aware of!

As for "not being a speed demon", what you have to remember is that the outboards available in the early 60's were fairly small. Moesly raced the early 21's with a pair of 110 hp Mercs which is why he didn't run much over the mid 40's. It's actually a pretty fast hull if you add more power, and I think Island Trader has seen well over 50 mph with that 383 stroker motor he put in his 21! But you're right, the boats rode so well in rough conditions that Moesly was very competitive with and often beat 30' inboards running twin 500 hp I/O's! And most of us that run offshore are more impressed with rough water speed capability than ultimate speed in flat water!

Gillie;
Remember you can only be original once! If you don't do any other mods, and you throw the OB on her she now becomes a modified mutt. I would go in line or SBC. The only thing on a sb, would you have to split your engine box for it to fit?

Thanks Terry.
I concur. I am very much leaning toward the inline. Haven't figured out the fine details of the stroked inline yet but I'm really leaning that way.

I was very impressed by your expansion project but I'm not that gifted. Granted, a sbc would be a more logical choice, I love the inline idea. Any feed back on drive choice and compatibility would be appreciated.

McGillicuddy - got to ask........
1. Have you run your Moesly in rough choppy waters, and can you comment on the reality of the ride.....as it compares to other boats?
2. Do you have any video of the same ?
I'm fascinated with this particular model....I see it as potential " near perfect " design for fisherman who want this size for trailer ability, cuddy protection, but hard core hull to fish harsher conditions....run longer, faster, better in typical ocean chop. I fish the ocean in a 21' boat up here in New Jersey, and while I pick my days for calm seas, I do some long runs up and down the coast.
So, whatever you can share appreciated......

B,
Sorry, not really, only video I have is pretty boring. took her on some mixed up chop but nothing to brag about. I think the greatest testament to this boat is the mid '60s run of race results.

Followed by Bushwacker's stories of his numerous crossings to Bahamas, where in all boats, big and small would tuck in behind Bob Reiland's 21 "Unohu" and relieve some of the gulf stream pucker factor.

I aint got no friends who'll follow me in rough western swells so it's hard to get video in 4-6' seas.
If you want to send me a go pro and a decent drone, i'll Shanghai some gamers and drag them out to operate the drone to get some viddy, while i negotiate the swell. ;)

I don't remember what 21 you're in but with the number of well priced 23 Sceptres I see from MA to FL, I'd be looking for one of those.

I'm fortunate to have a cream puff 96' V21 with etec 200HO .....looks new.
I've been a casual shopper for a Sceptre, but haven't found package to make it worthwhile to date. I'm in no hurry........but the Moesely 21.....is the " holy grail" :)
(assuming the ride is as good as reported)

Here you go. Mind you it is not by any means a treacherous sea state but the folks in my 23 were holding on for dear life while Terry and crew where sipping cocktails. The only way I can describe how the Moesly 21 appears to ride from a different boat is "squishy" meaning it would move up and down but never abruptly or with a bang. Terry did cross my wake before we started recording and it did so with no bang or list.... just rise and fall at a level plane.

My only other observation is that the Moesly 21 is not your average 21 in overall size. I will find the picture I took and can tell you it towers in overall size over my 23' and the 25'. I often wonder if it is 21' at the waterline where boats should really be measured.

https://www.youtube.com/watch?v=EgIQ43ZmyrE

Kmoose speaks truth, The 21 is HUGE. Here's a few of Island Trader's 21 next to Blue Heron's 25 Seafari.

I had a Marine well versed in towing on the route tow mine from Detroit to San Diego. He commented on several white knuckle moments when the wind would catch it and shake his 7.3L F350. I kind of freaked out about its size when I saw it turn the corner onto my street. Another friend who has towed it with his dually Chevy 3500 duramax, was also surprised by its mass.

Saw that......and while appreciated, it's only a teaser as the boat turns away instead of going across the wake, close up, and continuing alongside.

That's likely a near perfect boat for me because I like everything about it - the concept, and the reality. I can't figure why a boat like this doesn't exist today for people such as me who want a trailerable cuddy specifically made for long ocean runs and fishing. Overbuilt to take nearly any appropriate sea conditions, generally meaning 3'-4' chop and swells for miles of running!!

It`s a tough market.

I was up at R n R talking with Matt a couple of months ago.
They are building a 42 Conch and he told me the material cost to go from a 27 to a 30 was
negligible.

The new Barker 26 bay boat is north of 150.
An Albury 23 is 85 stripped. Go figure.

Not easy to build the 21 and make money.
3rdDay has been trying to make it work for a while now.
A mold is into 6 figures.

When I first saw the 21, my jaw just dropped.
I could stand on the keelson and look up to see outta the hull.
I spent the first few minnows sitting on the floor of the hanger
just studying her entry and steps.

That is Skipper T and Bowrider`s hull.
The center panel "Bulb" is massive when compared to a 23.
I suspect this is one of the secrets of the ride of the 21 vs the 23.
The steps are a good bit taller as well, but the bulb is freakin huge.

When you think about re-entry, what hits first?
That massive bulb does.
The VDH panels receive the water at decreasing angles
to relieve surface tension and most importantly aerate the water
which will now compress a tad when landing.

This also adds lift as the decreasing angles trap the air as the water
rolls over the steps.

Terry`s ride is indeed genteel.

Hey GFS, what's the sound the "decreasing angles" of the VDH hull makes as it re-enters the water.....woosh! There is a difference........:)

Continuing speculation......anyone know why the great 21' hull wasn't utilized into the 23 ? I understand that the 23 hull is good, but not as good.....

Chuckles boat goes woosh woosh woosh.
If you are getting wet or bouncing, you need to put the hammer down.

Yours sounds just the same.

Tried to email you a long reply to this post with an attachment but got a failure notice. I'll try to resend it if you'll PM me with a good email address.

Just sent it to you.......

Do tell, Denny...

Back to the repower, the stroked 250 (292) has got my fancy but First Mate Marine is having trouble calling me back...
Any input from the mechanical wizards on here, or your wize, wrench-wielding friends.

My understanding is that merc only produced the 200 hp Mercruiser configuration for a year, 1969, using the 292 w/MCM II drive - some bastardization of the sideways lifting elgin style lower er sumpin'. Can I mate an inline to an alpha or bravo drive, or am I stuck with the MC 1?

I'm finding a few ci 250 to 292 conversion threads but no real evidence of success. The guys selling these 292 blocks arent the most responsive ...

http://www.jasperengines.com/authentic-custom-engines

Gillie,
Jasper is employee owned and somewhat geared toward the vintage/ antique crowd.
They should have answers for you regarding drive compatibility and long stroke longevity
vs a more over square design with lower side loading of the piston skirts.

Did you send via PM or email? Still don't have anything on either.

Nothing here either.
Over.

I sent my email which is bhgreene2@gmail.com

I was just being a jackass.
Over.

email resent w/o failure message this time.