Moderated Discussion Areas
  ContinuousWave: Post-Classic Whalers
  Repowering a Dauntless 15

Post New Topic  Post Reply
search | FAQ | profile | register | author help

Author Topic:   Repowering a Dauntless 15
JohnJ80 posted 04-07-2003 09:51 PM ET (US)   Profile for JohnJ80   Send Email to JohnJ80  
I came across a deal on an Evinrude 75Hp Ficht 2003 motor. What I have now is a mid 90's 70hp Johnson 2 stroke.

I like the evinrude since it lists a big alternator - 60A compared to the 15A johnson that I have (for all sorts of reasons). I also have some mechanical issues with the Johnson.

Plus the deal now is that if you buy Evinrude before 4/15 they give you a seven year warranty.

What I am concerned about is the weight of the newer motors. My motor is about 250lbs, the Evinrude (and all the others, 4 strokes included) all are 350lbs or so.

The guys at Whaler seem to think that this could cause a problem with the scuppers and that the extra weight could cause porpoising.

Anyone have any experience with a heavier motor on the D15?


Perry posted 04-08-2003 02:41 AM ET (US)     Profile for Perry  Send Email to Perry     
The 75 Ficht is a great motor but is heavy. It's a V4 and is over 350#. The 115 Ficht weighs the same. What is the max hp and weight limit for your boat?
andygere posted 04-08-2003 03:58 PM ET (US)     Profile for andygere  Send Email to andygere     
Find a 100 pound wife, friend or neighbor kid, launch the boat and have him or her sit on the cowling of your motor (only when it's not running) to get an idea of the static trim with the heavier outboard.
captbone posted 04-08-2003 07:44 PM ET (US)     Profile for captbone  Send Email to captbone     
You would have to buy new controls for $300.00 but I would put the 90 hp Yamaha 2 stroke on that vessel. I feel it is a lightweight, economical engine that would be well balanced for that boat. It will also be cheaper than evinrude. I would go with the 90 yamaha first, it may seem like alot of power put the engine would be great on that hull, not a overpowered monster.
JohnJ80 posted 04-08-2003 10:57 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
100lbs just doesn't seem like all that much. I do know that when I stand in the back - with my old flap type bailers, i did get some water in. But that is alot more than 100 lbs!

Whaler has a service bulletin about an older Honda motor (4 stroke) from a few years ago. Apparently when you put it on a D15, because it weighed 370lbs or so, it caused porpoising.

Whaler CS says that the center of gravity can move to far back.

Now, I am adding a trolling battery under the console (50lbs). Wouldn't that help to ballast it properly?

Does anyone have a heavy motor (like 350LB) and do they have the porpoising problem. Can it be solved with a Doel Fin or equivalent?

I don't want to put the 90HP on. I live on a buy waterway with lots of water police. That would be asking for a hefty ticket.


Tallydon posted 04-10-2003 09:20 PM ET (US)     Profile for Tallydon  Send Email to Tallydon     
I owned a d15 and had a 50 4 stroke Merc on the back. It did porpoise a lot until I put on a doel-fin. That helped, but I still had the balance out the weight especially when heading into the wind.
JohnJ80 posted 04-10-2003 10:17 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Just an update.

The dry weight as listed by evinrude is 369 lbs. However, the specs the dealer has, for just the motor says 319 lbs.

In talking with BW, their service bulletin says that a older 50HP honda, which weighed 370 lbs had porpoising problems. The same bulletin also says that a 75Hp Merc of the same vintage, with a motor weight of 305 lbs was ok with no performance problems noted.

According to two dealers I talked to, they also said that the honda has more weight aft in the motor so it tends to act heavier than some of the 2 strokes like the Evinrude.

BW also suggested a thing called Turbo Lift from Grand Island marine. Apparently it works somewhat differently than does a doel fin etc.. BW says that this thing clamps on the motor - no holes drilled as with the other fins so it doesn't invalidate the motor warranty. BW also said that it had really great results on any boat that they tried it on.

In talking to Grand Island Marine, they claim that it will reduce planing revs by up to 30%.

So, I think that the Evinrude 75HP FICHT will repower this boat nicely, the additional 14 lbs (over the older Merc) shouldn't make any difference. If so, I think this Turbo Lift Fin will solve the problem if there is one.

Any comments?


Perry posted 04-11-2003 01:02 PM ET (US)     Profile for Perry  Send Email to Perry     
The Ficht weighs 369 lbs. What is the max engine weight for your boat as listed on the capacity plate? If 369 lbs excedes that weight, I would not put it on, nor would the dealer.
PMUCCIOLO posted 04-11-2003 09:40 PM ET (US)     Profile for PMUCCIOLO    

Having owned a 15 Dauntless, I can offer a few first-hand observations. My boat, powered by a 60 Evinrude, had satisfactory performance. It planed well, rode smoothly and was dry for a boat of its size. However, the boat (even when lightly loaded) had drainage problems with which I couldn't live.

I did, during my shopping, go out for a test ride on a 15 Dauntless with a 75HP Mercury. It FLEW! The boat's performance was exhilarating!

If you experience no drainage issues of concern, I'd opt for the 75 Mercury (two-stroke). I would not recommend putting a heavier engine on the boat. If you have drainage problems, they'll most likely be worsened. If you don't have drainage problems, the heavier engine may create them.

I hope that this is of some benefit to your decision-making.


JohnJ80 posted 04-17-2003 05:18 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
The 75HP FICHT shipping weight is 369 lbs. The actual engine weight per the mfg service manual is 319 lbs. The 75HP 2 stroke merc actual engine weight is 305 lbs. So there is a 14 lb difference - not much.

BW tech support says that there is no problem with the 305 hp Merc 2 stroke. There is a service bulletin that says there is a problem with the honda 70HP (4 stroke). When you take off the engine covers you can see why.

The Honda has a major assembly at the valve heads that a 2stroke doesn't have. It alone weighs about 60-70 lbs per teh dealer. This is positioned well aft on the engine - not over the transom clamp so it has the effect of being at the end of a lever arm. On top of that the Honda is a 370 lb motor vs the 305lb Merc or 319 lb Evinrude.

Boston Whaler tech guy also recommended a different fin from a company called Grand Island Marine (321-452-8126). This fin works on a different principle than Doel style fins. It also does not require any drilling of the engine. BW says they have seen this thing work very well and substantiated much of what the mfg claims.


BWdaunt18 posted 04-17-2003 05:55 PM ET (US)     Profile for BWdaunt18  Send Email to BWdaunt18     
I owned a Dauntless 13 with a 40 Yamaha. I had two six gallon tanks, battery, gear and a fishing seat in the rear. I took in some water through the scuppers. I fixed the problem with the installtion of Rabuds. Rabuds are one-way valves with ping pong balls in them. They worked great.

If it's water you are worried about, get the engine you want and a set of Rabuds.

I agree with some comments above...go with the Yamaha. They make a great outboard.


Perry posted 04-17-2003 08:24 PM ET (US)     Profile for Perry  Send Email to Perry     
My brother has a 115 Ficht on his boat. This is the same 105 cubic inch V4 as the 75 HP Ficht. According to the owner's manual, the motor weighs 369 lbs dry. Add oil to the lower unit and it weighs over 370 lbs. The carbed 105 ci V4 Johnsons weigh 319 lbs. The Ficht are a bit heavier.
captbone posted 04-17-2003 08:38 PM ET (US)     Profile for captbone  Send Email to captbone     
I would still look at the 90 Yamaha 2 stroke. It would give you the same perfomance as the 75 fitch, is lighter. Also of people say the yammi 2 stroke is equal to a 80hp becuase it does not have alot of cc. Plus you just remove the 90 sticker from the stern of the hood and people will think it is a 50 because it is that small. I would strong rec. against the 75 fitch because of the weight. Maybe the 70 tohatsu lpdi, or the johnsuzuki 70 4 stroke but IMO the fitch is too heavy. If you can wait until july for the new etec. They are going to be amazing and the future of Evinrude. Just my 2 cents.
JohnJ80 posted 04-18-2003 07:21 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Thanks for all the dialog on this very helpful. Here is what I found out.

The 75HP V4 carbed johnson weighs in at 314 lbs (motor only). The 75HP V4 FICHT Evinrude comes in at 324.5lbs.

The dealer set up three similiar boats (whalers) last year with no problems. They handled if fine.

I already have the Rabuds installed and I keep the boat drysailed on a Jet Dock (very cool product incidentally, I had minor water problems with the old flapper style drains when I stood on the rear corner of the boat. I did not have any problems after Rabuds.

The deal on this motor is just too compelling. Plus, I worked out a swap deal with the dealer if there is a problem with the motor in the first 30 days (I will know in the first 30 minutes). He also sells merc, yamaha, evinrude/johnson and Honda. So, I have the yammie fallback position if need be.

i will put a detailed summary on here after i get it all in the water in a couple of weeks.


Perry posted 04-18-2003 09:46 PM ET (US)     Profile for Perry  Send Email to Perry     
What are the maximum weight and horsepower limits for the Dauntless 15 as sated on the capacity plate?
JohnJ80 posted 04-18-2003 09:55 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
I know for sure that the HP limit is 75HP. I don't recall the total weight, but it was quite a bit. I think 1250 lbs (or more) or 6 persons. There is no max weight listed for the motor.


captbone posted 04-19-2003 04:16 PM ET (US)     Profile for captbone  Send Email to captbone     
I have never heard of the new 75 hp Johnson Carb????
lhg posted 04-19-2003 05:57 PM ET (US)     Profile for lhg    
You're getting scammed by the Dealer on that engine weight. The 2003 Evinrude catalog shows the ENGINE weight as 369#, as mentioned. There is no such thing as shipping weight as used with outboards. What is that supposed to mean - the weight in the box?

Call Bombardier's regional sales office for the correct information.

I also believe that 75HP Ficht engine is too heavy for the 15 Dauntless. Sounds like an unscrupulous dealer chasing a "compelling" sale, mis-representing the weight like that, and no less for a boat that is very sensitive to engine weight.

Perry posted 04-19-2003 10:54 PM ET (US)     Profile for Perry  Send Email to Perry     
I agree with Ihg. I've been saying all along that the 75 Ficht weighs 369#. Look here
That motor is going to bee too heavy for your boat. I bet 369# is beyond the weight capacity and if the dealer agrees to put it on for you, he's nuts.
JohnJ80 posted 04-21-2003 11:43 AM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
This whole weight thing is driving me crazy.

I called Bombardier tech support today. They started looking at this and they also think that their listed dry weight is way wrong. They are pretty sure it is shipping weight (motor + pallet + drag link + box+ manuals) and not just motor hanging from a hook.

The factory guys are going to go out and weigh all the motors again. They think their specs are bad across the board now.

The 2002 service manual (not owners manual) lists the wieght at 324.5lbs. 2003 is basically/virtually the same motor.

For reference, a honda 75HP weighs in at 373lbs. Everyone that has handled the 75HP FICHT says that it is considerably lighter - estimates (qualitative) run 50-70lb guesses.

Bottom line - no one really knows what this weighs but everyone, factory included, is pretty sure the 369# number is wrong by a fair amount. No one, BW included, really knows what this will mean in performance but even they think that at 320# there should be no problem.

The dealer here is very reputable. Based on all this discussion, if this doesn't work well, they will put anything I want on the boat. They want this to be right and they put that in writing.

So, its going to be a bit of a science project. The motor is going to go on the boat. If I don't like it, it comes off. If that is the case, then I will either swap it out with the Merc 75HP 2 stroke or a Yamaha 75HP 2 stroke - this dealer sells either (plus Johnson, Honda too).

There are a ton of other factors in this as I talk to all the those involved (Bombardier, Merc, Dealers, Boston Whaler, others). Not only is the weight of the motor important, but where the weight is carried on the motor itself. For example, weight carried aft on the motor is at the end of a lever arm on the transom. This has the effect of acting much 'heavier' than if the weight is closer to the front of the motor.

Going to learn a lot in the first 30 mintues the boat is in the water. My options on this will be to go Evinrude->Yamaha->Merc if this doesn't work.

thanks to all for your help and opinions on this. Not a simple solution but should come out ok one way or another. I will let you know how it works out.


lhg posted 04-22-2003 04:56 PM ET (US)     Profile for lhg    
Well, if all you are saying about Bombardier is correct, it's well they should be getting out of the outboard business!

Engine manufacturers are notorious, especially Yamaha, for under reporting the weight of their engines, because with the new technology, the increased weights are getting to be an issue. Suzuki is so sensitive about the issue, their 2003 catalog doens't even give weights, also a mistake! But over reporting engine weights by 25% sure makes no sense to me. The engineers at the factory don't know what an engine weighs? I'm not buying it.

PMUCCIOLO posted 04-22-2003 10:20 PM ET (US)     Profile for PMUCCIOLO    

If Yamaha underreports the weights of its engines, then why do the Mercury & Yamaha engines with shared technology (e.g., F60) have weight values in the Mercury literature almost identical to those in the Yamaha literature? I know, I know, it's a PLOT! Just a little jest!

It would be nice if the manufacturers reported the "wet" engine weights (i.e., with oil and lubricant reservoirs full), as opposed to providing numbers which can be misleading to the untrained eye.


Bigshot posted 04-23-2003 11:54 AM ET (US)     Profile for Bigshot  Send Email to Bigshot     
Suzuki reports the DF60/70 is 338lbs. OMC states it at 359.....same engine, go figure.
lhg posted 04-23-2003 04:47 PM ET (US)     Profile for lhg    
Paul - Both the Yamaha/Mercury produced 4-stroke Yamaha 80/100's were under reported on weight at 356 lb, while Mercury showed the same engines at 386 lb. Yamaha has now increased the weight listing on those engines to be closer to Mercury.

Weight is so critical these days, that under reporting it can increase sales over a competitor. But I don't think it's very fair to the consumer. BW had a situation like this a few years ago also.

PMUCCIOLO posted 04-23-2003 06:48 PM ET (US)     Profile for PMUCCIOLO    

I agree completely. The difference of even a few pounds on the 15 (between the two-stroke and four-stroke engines) concerned me when I was shopping. It took an informal survey to locate the actual weight of the 3-cylinder two-stroke 70 OMC engine to which I compared the potential powerplants.

It is imperative (and unfortunate) that the consumer must be(ware) of this misinformation. For two-stroke engines with remote oil tanks, the extra weight of the full tank and plumbing must be considered as well.


JohnJ80 posted 06-07-2003 03:11 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
I have mostly completed this project and I thought I would share the results to date.

The engine is a 2003 75HP Evinrude FICHT with an aluminum 13.75x15 prop. The motor is mounted one hole up from all the way down which puts the AV plate at about 1/2" above the bottom of the hull. I just mounted a Grand Island Marine Turbo Lift Fin on the motor as recommended by BW tech support.

Before mounting the fin, the boat had a tendency to behave bow light taking waves harder than with the old 70HP 2 stroke johnson i had before. The boat also has a tendency to porpoise such that I really had little trim range unless the water was dead flat calm. Motor needed to be trimmed all the way down most of the time (<37mph)

This improved markedly when I raised the motor one hole to its present position. I suspect that this will improve further when I raise it another hole.

When I added the turbo lift fin, the performance change was dramatic. The hole shot improved so that the boat was on a plane within about a boat length from dead stop. The porpoising stopped, the ride was dramatically softer and smoother - pretty much how it was with the 70HP Johnson. The trim range improved so that it is essentially what it was with the 70HP Johnson - most often at about 25% up from all the way down. The minimum plane speed decreased from about 17-19mph to 13-15mph.

Here are the numbers:

0% trim
2800 RPM
13-14mph minimum plane depending on sea state

25% trim
3100 RPM
19mph (just raised trm from prior setting)

25% trim
5000 rpm (WOT)

35% trim

Conditions were 5kn of wind, flat water intermixed with a fair number of boat wakes - not flat calm. Passenger load was about 305lbs (two passengers) sitting on the driver's seat. I was able to get the trim up to 40%-45% in flat section of water without porpoising. I think I could get this over 50mph in the right water conditions - total flat calm, no boat wakes, no wind.

At trim down 0-15% I still get rooster tails off the lower unit. I think this means that the motor is still down too far. Grand Island Marine thinks I can move the motor all the way up, but I think I will go just another hole, to the 3rd out of 4 up which should put me about 1-1/4" above the hull bottom.

This top end is way more than enough for me. Just to get more trim range, I may switch to a more cupped prop and/or one that provides more stern lift. This should give me more control over the bow position to control the ride plus increase fuel efficiency.

Qualitative Results:
1. Adding the Turbo Lift decreased the engine noise at WOT about 30-50% vs without it. There was a very significant reduction in noise at the driver's station with the fin in place. It was possible for the two passengers to easily converse is slightly above normal conversational volume.

2. The Turbo Fin greatly improved the ride and trim range.

3. Turning control and handling precision seemed to improve by adding the fin. Steering seemed to require less force.

4. Fuel economy before adding the fin was significantly better than with the 70HP 2 stroke. I expect this will increase with the better trim range.

Conclusions that I draw from this are:

1. This motor is not too heavy for this boat. In point of fact, it behaves pretty much like the 240lb 2 stroke Johnson in terms of trim range. However, a fin is required, as it was on the 2 stroke - more so with the FICHT engine. The average trim range is marginally less (maybe <5% of full scale - i.e. 25% vs 30%). Enough less that it is difficult to quantify on the trim gauge.

2. The vertical hole position of the motor makes a large difference in the performance of the motor on this boat. Not just only in efficiency but also in ride quality. Too low pounds in any waves. Porpoising is increased by going too low and can be decreased by raising the engine from its lowest setting. I think the D15 is very, very sensitive to this position. Since I still get a rooster tail (~ 4-5') at 0% trim at 30mph, I think the motor is still too low.

3. The Hydro Lift seems to be a good product. The difference in hole shot, porpoising, engine/exhaust noise and handling is significant. This device appears to be better than the Stingray that I had on the old motor. However, I didn't try one on this motor since the Turbo Lift does not require drilling of the AV plate so results here are not conclusive.

4. 13.75x15 aluminum seems to be a good prop for this boat. WOT rpm is supposed to be in the range of 4750 to 5200 rpm. This prop meets that critieria and sits nominal.

5. The 75HP FICHT is significantly quieter, uses less fuel and oil than the 70HP 2 stroke Johnson. It also has significantly more torque and gets out of the hole faster.

Projects to go the next step -
+ experiment with a prop that provides more stern lift to see if this improves the trim range.

+ Raise the motor up at least one hole or two (max up). Evaluate for blowout and larger/smaller trim range.

+ Experiment more with weight placement in the boat.



JohnJ80 posted 06-07-2003 03:29 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Forgot to add that in addition to passengers there was 15 gallons of fuel under the driver's seat.


rkong posted 06-10-2003 03:17 AM ET (US)     Profile for rkong  Send Email to rkong     

What are you using to measure your speed? Are you using a GPS? I get no where near your numbers with my D15. And I can't even get those numbers with the prop calculator assuming no slip. They seem to be way off. On mine, turing a 17" pitch at 5000 RPM I can get around 31-31MPH or so.

JohnJ80 posted 06-16-2003 03:50 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
I came to the same conclusion yesterday. I think my FF is out of cal for boat speed. However, the speedo says that i was doing about 40mph at the same time. So, I am not exactly sure what is going on - I can tell you that I was going faster than i ever did with my 70HP 2 stroke.

i'm going to raise the motor up a hole again tonight. If the batteries in my GPS are good, I will give it a shot and see.

once this is done, then its the prop experiments. if the hole up works then i am going to get a 13.25x15 stiletto and see how it goes.


JohnJ80 posted 06-19-2003 11:09 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Just raised my motor to the top hole (all the way up). AV plate looks like it is about 1.25-1.5" above bottom of boat. Works great. I still need to do more testing, I just didn't have time tonight after raising the motor.

Gained about 200 RPM and 2 mph by the speedo. Trim range has increased about 25% over what I had before, ride improved a ton in chop and boat wakes (although I had limited time to test). Side rooster tails are gone, boat feels much better in the water and the engine never sounds like it labors even with a full load at speed with full trim in (motor all the way down). Steering is easier. I can trim up in flat water more before porpoising starts (about 50% of full trim).

I'm going to get a new stiletto 13.25x15 prop and check that out. That is supposed to give me more trim range per the prop guy plus lower planing speed etc...


JohnJ80 posted 06-23-2003 10:45 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Thought I would keep this up to speed just so anyone who might be interested in a similar path could see how this all came out.

I just received a Stiletto 13.25"x15 prop as recommended by Stiletto.

There was a noticeable improvement again in ride and performance. The stern seems to ride higher, the trim range is greatly improved. I can now trim up reliabily to 30% up in virtually all conditions and I was able in very flat water with perfect conditions (no wind or boat wakes) to get the trim up all the way without porpoising. Top speed on my pitot tube speedo was 44mph (which I think is off a bit) but shows as up from 38mph with the old Al (13.75x15) prop. Qualitatively, it is fast, faster than I am comfortable going on the water.

Qualitatively, the boat takes waves even better going very smoothly through chop and boat wakes. The ride has improved to be better than it was with my 70Hp 2 stoke - performance that I was happy with had the engine not been near its end. This has been somewhat of a science project, so I am not sure if the changes I made here would have benefitted the old installation or if the setting of that set up was optimal.

Downside is that I might be a tad toward over propped (but I don't think so). The WOT RPM is 48-4900 with 310 lbs of passengers, full 15 gallons of fuel, dual batteries, manual says the range is 4750-5250. I need to run this with just my daughter and me on board. With the old prop, we hit 5100 rpm at about 50% trim. However, that could have been because the other prop wasn't staying hooked up as well. 4900 RPM that I got was the same as we got on the boat fully loaded with both my kids on board with the old prop but a lot less trim. So, I need to do the apples to apples thing on this.

The other issue is that I don't think I have the full 10 hours on the motor above 2000RPM (or 5, I can't remember which). At this point the computer on the motor changes the timing for higher performance and reduces its oil consumption, so that may have some effect on the performance and rpm too.

So, the combination of the new motor, fin, hole position and SS prop has made a huge difference. This setup works great on this boat exceeds the setup on my old 70HP Johnson 2 stroke for ride and performance. That set up was pretty good, it was an all weather, all condition comfortable rig but this one is better.

JohnJ80 posted 07-02-2003 05:37 PM ET (US)     Profile for JohnJ80  Send Email to JohnJ80     
Further testing with the new prop:

flat water, downwind with 10 gals of fuel and just me on board I can trim the motor up to 100% of its trim range with out porpoising. WOT on speedo shows about 45mph, tach shows 5100rpm. I don't believe the speedo but it is fast. I'm thinking it is pretty close to 40mph.

5100rpm says prop is ok since range is 4750 to 5200.

Looks like this is set up for me.


boatn posted 09-09-2006 12:51 AM ET (US)     Profile for boatn  Send Email to boatn     
So is the final verdict in? How much engine weight can you put on a 15 Dauntless? I can get a good deal on a Mercury 75hp 4 stroke and I'm thinking about putting it on my 15 Justice/Dauntless. The NADA site shows the weight of Mercury's 75hp 4 stroke as 384 lbs. Do you think that is too heavy?
Jkcam posted 09-10-2006 04:13 AM ET (US)     Profile for Jkcam  Send Email to Jkcam     

Thanks for the pile of data................but........

Ever get any batteries for that GPS so there might be a degree of accuracy to the speed?

Mambo Minnow posted 09-10-2006 07:42 AM ET (US)     Profile for Mambo Minnow    
I sold my D15 to fellow forum member Ali. He repowered my Merc 60HP 2 stroke with an Evinrude E-TEC 75HP. Delighted with results. I believe the Merc 60 2 stroke weighed 305 lbs. I really enjoyed the D15, and observed it was a very "tail heavy" boat. I agree with posts that too much additional weight on transom would lead to terrible trim and balance issues.

Post New Topic  Post Reply
Hop to:

Contact Us | RETURN to ContinuousWave Top Page

Powered by: Ultimate Bulletin Board, Freeware Version 2000
Purchase our Licensed Version- which adds many more features!
© Infopop Corporation (formerly Madrona Park, Inc.), 1998 - 2000.