25" or 20" Outboard for Typhoon

Discussions about Cape Dory, Intrepid and Robinhood sailboats and how we use them. Got questions? Have answers? Provide them here.

Moderator: bobdugan

charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

25" or 20" Outboard for Typhoon

Post by charlesaf3 »

Hi,

I have a Typhoon weekender and it's time to repower it. I did a search here, but couldn't find a discussion of the 25" long outboard shaft for the Typhoon - is it a good idea, or is the 20" shaft better?

I'm looking at the mercury/tohatsu 5hp, gas, which comes in 20 or 25. The 25" is actually $10 cheaper, which is not exactly decisive.

I have the bronze bracket, not a regular outboard mount.

I'm on the Chesapeake, so nothing all that rough, but it seems like the 25 would be more likely to keep it's intake in the water. I'm worried the 25 will drag when tilted up.

Does anyone have any advice? Is the 20" sufficent enough so that I shouldn't overthink it
'
Carl Thunberg
Posts: 1285
Joined: Nov 21st, '05, 08:20
Location: CD28 Cruiser "Loon" Poorhouse Cove, ME

Re: 25" or 20" Outboard for Typhoon

Post by Carl Thunberg »

Is your boat on the hard? If so, you can see for yourself. Take a tape measure and measure the distance from the top of the motor mount down. Remember, shaft length is measured to the top of the cavitation plate.

I see this is your first post. Welcome to the Board! You will find this Board to be a valuable resource.
CDSOA Commodore - Member No. 725

"The more I expand the island of my knowledge, the more I expand the shoreline of my wonder"
Sir Isaac Newton
User avatar
wikakaru
Posts: 837
Joined: Jan 13th, '18, 16:19
Location: 1980 Typhoon #1697 "Dory"; 1981 CD22 #41 "Arietta"

Re: 25" or 20" Outboard for Typhoon

Post by wikakaru »

I have a Yamaha 2.5 with a 20" shaft. Here's a photo of how it looks tilted up:
DSC_7801a.JPG
Here's what a 20" Tohatsu 6HP looks like tilted up:
DSC_8524a.JPG
Note that the only way to get the Tohatsu to tilt up with the removable bronze bracket is to rotate it almost 90 degrees.

Here's what the Tohatsu looks like with the boat out of the water:
DSC_8354.JPG
My Yamaha 2.5 20" occasionally catches a wave when sailing on starboard tack and heeling well over, but not when the boat is level nor on port tack.

If I am single-handing and walk all the way to the bow with the outboard running, the exhaust outlet just above the prop lifts out of the water, but the cooling water inlet still stays submerged. If there are two of us on the boat and one is in the cockpit when the other goes to the foredeck, it stays in the water.

My advice is if you want as much as 5 HP on the boat, and if you expect to motor in large waves frequently, go for the 25". The problem with the 5HP Tohatsu is that it doesn't have an integral fuel tank (at least not the one I looked at) so you have to worry about where to store an external fuel tank. The Typhoon isn't designed for an external fuel tank as some of the other Cape Dories are.

I personally am happy with the 2.5HP 20" Yamaha, but that's because it suits the conditions I sail in. I found the Tohatsu 6 too much engine for the boat (the reason too much horsepower is a problem is that you can't maneuver at low speeds as easily because there is a lot of thrust even at idle speed). I found the original Evinrude 4 that was on the boat when I bought it pretty good, but old and a bit temperamental.

Smooth sailing,

Jim
You do not have the required permissions to view the files attached to this post.
User avatar
wikakaru
Posts: 837
Joined: Jan 13th, '18, 16:19
Location: 1980 Typhoon #1697 "Dory"; 1981 CD22 #41 "Arietta"

Re: 25" or 20" Outboard for Typhoon

Post by wikakaru »

P.S. The only way to get the Yamaha 2.5 to tilt up is to add a 1x2 on top of the outboard bracket to lift it up a bit...

--Jim
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

Thanks for the great replies.

The Mercury 5/Tohatsu (all the little mercurys are made by tohatsu now evidently) has an onboard fuel tank.

So it sounds per the above (thanks for the excellent pictures) that a 20" will generally serve, and that 25" isn't necessary? I was thinking things like walking to the bow when it's running, I'm 6'5 250 so that tends to push things down.

But I'd also prefer not to drag the prop in the water while sailing. It occurred to me I could put a taller wood block on, but in such case why bother getting the 25 (aside from the interesting fact it's $10 cheaper).

I also hadn't though about too much thrust at low speed. That could indeed be an issue at times. I just wanted to be able to make headway through a chop if necessary
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

I get the feeling I might be overpowering the boat. I'm not sure if I should be posting a link to online outboards here? But the 4hp is barely cheaper than the 5hp. The 3.5hp is notably cheaper, but I worry about powering into a decent wind with the 3.5?

Interestingly, online at least, the mercurys are cheaper than the Tohatsus
radsailor
Posts: 134
Joined: Feb 8th, '20, 12:52
Location: Typhoon Weekender LeisureLee

Re: 25" or 20" Outboard for Typhoon

Post by radsailor »

I had a 4hp mercury long shaft, that had more than enough power and tilted easily without dragging in the water.
However, because it was so temperamental I changed it for a short shaft 3hp Torqeedo. The prop comes out of the water in big chop and when I move forward of the cockpit.
It is powerful enough to move (slowly) through 20kt wind and waves. In calm conditions speed is about 3.8kts.

I am thrilled with the motor. No maintenance, no starting problems, no noise, light enough to easily take off is necessary ( I take off the tiller arm and battery and
and put them in the cabin when not sailing. If the battery is 50% or below I take it home to charge. I have two batteries.
User avatar
wikakaru
Posts: 837
Joined: Jan 13th, '18, 16:19
Location: 1980 Typhoon #1697 "Dory"; 1981 CD22 #41 "Arietta"

Re: 25" or 20" Outboard for Typhoon

Post by wikakaru »

charlesaf3 wrote:Thanks for the great replies.

The Mercury 5/Tohatsu (all the little mercurys are made by tohatsu now evidently) has an onboard fuel tank.

So it sounds per the above (thanks for the excellent pictures) that a 20" will generally serve, and that 25" isn't necessary? I was thinking things like walking to the bow when it's running, I'm 6'5 250 so that tends to push things down.

But I'd also prefer not to drag the prop in the water while sailing. It occurred to me I could put a taller wood block on, but in such case why bother getting the 25 (aside from the interesting fact it's $10 cheaper).

I also hadn't though about too much thrust at low speed. That could indeed be an issue at times. I just wanted to be able to make headway through a chop if necessary
I weigh about 200 lbs, and as I said my 20" shaft outboard will just start to lift the cooling system out of the water if I am single-handing and go to the bow, but not if someone else is in the cockpit and their weight is aft. Since you weigh more than I do you may find going to the bow without the cooling system coming out of the water more of a problem than I do. The little Typhoon is sensitive to weight distribution. +1 point for the 25" shaft.

I researched Tohatsu and Yamaha outboards back in 2018-2020 when I bought new outboards for my Typhoon and CD22, but I didn't look at the Mercurys at the time. I find it interesting that the Tohatsu brand 5s have external fuel tanks only, but the Mercury brand 5s have the internal/external option. The Mercury engines are reputed to have a block made by Tohatsu, but obviously other parts of the engine, including the fuel tank setup, differ. +1 point for the Mercury.

You might want to check the tilt mechanism on the Mercury before you buy. I have no idea if the Mercury and Tohatsu use the same tilt mechanism, but on the Tohatsu, you can only tilt the outboard up when the gearshift is in neutral, and you can only tilt the engine down when the gearshift is in forward. What a goofy setup. That little fact could potentially leave the outboard permanently stuck in the up position if, once you have tilted the outboard up, there isn't enough room to move that forward-mounted shift lever into forward. The first time I tilted my Tohatsu up I remember that I had a heck of a time getting it back down. I'm not sure, but I may have had to un-mount the outboard to be able to get the gear shift into forward to tilt the engine back down. With the bronze removable outboard bracket on the Typhoon, there is one magical way to twist the outboard while tilting it up that allows you to get the outboard to go back down again if the outboard mounting pad is not raised before you mount the outboard.

If you are considering extending the wooden mounting pad by an inch or two to make the engine tilt up (or actually, back down, which is the hard part) more easily, then the 25" shaft may make a lot of sense. It essentially becomes a 24" or 23" shaft depending on how far you extend the mounting pad. I didn't have to extend the mounting pad with my Tohatsu once I figured out the magic tilt trick, but I do have to extend the pad for my Yamaha 2.5.

I think the 20" is 5 pounds heavier than the 15", and I suppose the 25" is another 5 pounds more than the 20". It's something to consider if weight is an issue. I like to un-mount my engine after launch day, and I do that from the dinghy on a mooring, so weight is an issue for me. The manufacturers always give the weight specs for the lightest/shortest set of options in an outboard family, and finding out how much the longer shaft models weigh isn't easy. -1 point for the 25" shaft if you care about weight.

If you are dealing with a local dealer who has these outboards in stock, you may be able to sweet-talk them into letting you try one or the other (20" or 25") with the promise that you will buy whichever one of the two fits best on the boat. If the engines have to be ordered and shipped, then they obviously won't want to do that.

Smooth sailing,

Jim
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

I'm looking at an online dealer. I'll post the link here, if someone could let me know if that's against policy. I've never dealt with this place before myself, but they have all the data nicely arranged. Looks like the 25 is only 1 pound lighter. I'm guessing the 4 and the 5 are basically the same motor with a different carb from the stats.

https://onlineoutboards.com/collections ... ard-motors

I gather (perhaps incorrectly) that Tohatsu makes all the little mercurys now. But that's from online research... so I'd be happy to be corrected. Per that link the Tohatsu doesn't have an onboard tank and the mercury does, as you said, huh. I'm surprised they are spec'd differently, but an onboard tank is clearly key.

Mercury warranty support and service would be much easier in my area.

Thank you for letting me know about the tilt issue. I could see that driving me around the bend.

I'll be keeping it at a dock, so wrestling the motor in and out of a dinghy won't be an issue thankfully.

the 3.5 is a lot lighter. Would 3.5 be enough power for a cape dory generally? Say 4 knots into a stiff breeze? Do you feel the 2.5 is underpowered?
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

radsailor wrote:I had a 4hp mercury long shaft, that had more than enough power and tilted easily without dragging in the water.
However, because it was so temperamental I changed it for a short shaft 3hp Torqeedo. The prop comes out of the water in big chop and when I move forward of the cockpit.
It is powerful enough to move (slowly) through 20kt wind and waves. In calm conditions speed is about 3.8kts.

I am thrilled with the motor. No maintenance, no starting problems, no noise, light enough to easily take off is necessary ( I take off the tiller arm and battery and
and put them in the cabin when not sailing. If the battery is 50% or below I take it home to charge. I have two batteries.

I thought about electric, but the price would be far more expensive and the pain higher it appears.
User avatar
wikakaru
Posts: 837
Joined: Jan 13th, '18, 16:19
Location: 1980 Typhoon #1697 "Dory"; 1981 CD22 #41 "Arietta"

Re: 25" or 20" Outboard for Typhoon

Post by wikakaru »

charlesaf3 wrote:I'm looking at an online dealer. I'll post the link here, if someone could let me know if that's against policy. I've never dealt with this place before myself, but they have all the data nicely arranged. Looks like the 25 is only 1 pound lighter. I'm guessing the 4 and the 5 are basically the same motor with a different carb from the stats.

https://onlineoutboards.com/collections ... ard-motors

I gather (perhaps incorrectly) that Tohatsu makes all the little mercurys now. But that's from online research... so I'd be happy to be corrected. Per that link the Tohatsu doesn't have an onboard tank and the mercury does, as you said, huh. I'm surprised they are spec'd differently, but an onboard tank is clearly key.

Mercury warranty support and service would be much easier in my area.

Thank you for letting me know about the tilt issue. I could see that driving me around the bend.

I'll be keeping it at a dock, so wrestling the motor in and out of a dinghy won't be an issue thankfully.

the 3.5 is a lot lighter. Would 3.5 be enough power for a cape dory generally? Say 4 knots into a stiff breeze? Do you feel the 2.5 is underpowered?
Sticking with a brand that is popular in your area is a good idea to obtain future support. You should research whether the warranty will be honored if you buy online. I know some manufacturers will not honor a warranty unless the new outboard was initially prepped by a dealer and the sale registered with the manufacturer via the dealer. Outboards are usually shipped without any fluids, and I guess their argument is that the dealer has to do the prep so they know it is done right.

As to sizing, the 2.5 HP Yamaha will push my Typhoon just to hull speed--about 4.9 knots--at wide open throttle in calm water, but no faster. It's a good get-home-in-normal-conditions motor. It could probably manage 4 knots into a good breeze if the seas are flat, but just barely. The 6 HP Tohatsu I use for my CD22 is really too much motor for the Typhoon. If I remember correctly, it would get the Typhoon up to 5.5 knots in flat water, and have plenty of power in reserve to punch through a big chop, but as I mentioned, had a little too much thrust at idle for low-speed maneuvering. You won't go wrong with a 3.5 or 4 HP motor, horespower-wise. As a point of comparison, I wrote a post on using a 62-pound thrust trolling motor on a Typhoon (http://www.capedory.org/board/viewtopic.php?f=1&t=38397), which would reach a top speed of 3.5 knots in flat water.

I have to say, I've been in wind-against-current conditions off of Cove Point on the Chesapeake, and the waves were so short, steep, and large that the 35-HP diesel on our Crealock 34 could only push us at 2.5 knots. If you expect any outboard to push a Typhoon into those conditions, you may want to re-think your expectations and instead pay close attention to the weather forecasts. If the weather is forecast to be that snotty you probably shouldn't be out in a Typhoon to begin with, and if you happen to be caught out in an unforecast squall, a good option would be to run downwind to a different harbor if you can instead of motoring into it. That's exactly what we did on our Crealock 34 that day, so there would be no shame in doing it on the much smaller Typhoon.

Anyway, it sounds like weight isn't so much of an issue for you, but being able to go to the bow with the motor running and wanting to deal with some adverse weather is. In your situation my first choice would be the Mercury 5 XL (25") shaft, and my second choice would be a 3.5 HP long (20") shaft.

Smooth sailing,

Jim
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

wikakaru wrote: Sticking with a brand that is popular in your area is a good idea to obtain future support. You should research whether the warranty will be honored if you buy online. I know some manufacturers will not honor a warranty unless the new outboard was initially prepped by a dealer and the sale registered with the manufacturer via the dealer. Outboards are usually shipped without any fluids, and I guess their argument is that the dealer has to do the prep so they know it is done right.

As to sizing, the 2.5 HP Yamaha will push my Typhoon just to hull speed--about 4.9 knots--at wide open throttle in calm water, but no faster. It's a good get-home-in-normal-conditions motor. It could probably manage 4 knots into a good breeze if the seas are flat, but just barely. The 6 HP Tohatsu I use for my CD22 is really too much motor for the Typhoon. If I remember correctly, it would get the Typhoon up to 5.5 knots in flat water, and have plenty of power in reserve to punch through a big chop, but as I mentioned, had a little too much thrust at idle for low-speed maneuvering. You won't go wrong with a 3.5 or 4 HP motor, horespower-wise. As a point of comparison, I wrote a post on using a 62-pound thrust trolling motor on a Typhoon (http://www.capedory.org/board/viewtopic.php?f=1&t=38397), which would reach a top speed of 3.5 knots in flat water.

I have to say, I've been in wind-against-current conditions off of Cove Point on the Chesapeake, and the waves were so short, steep, and large that the 35-HP diesel on our Crealock 34 could only push us at 2.5 knots. If you expect any outboard to push a Typhoon into those conditions, you may want to re-think your expectations and instead pay close attention to the weather forecasts. If the weather is forecast to be that snotty you probably shouldn't be out in a Typhoon to begin with, and if you happen to be caught out in an unforecast squall, a good option would be to run downwind to a different harbor if you can instead of motoring into it. That's exactly what we did on our Crealock 34 that day, so there would be no shame in doing it on the much smaller Typhoon.

Anyway, it sounds like weight isn't so much of an issue for you, but being able to go to the bow with the motor running and wanting to deal with some adverse weather is. In your situation my first choice would be the Mercury 5 XL (25") shaft, and my second choice would be a 3.5 HP long (20") shaft.

Smooth sailing,

Jim
A very good point about warranty. I assumed it would be treated like any other out of state purchase. I should check that.


Also a good point on the weather. You now really have me torn between the 5 and the 3.5. The truth is where I sail it's not really going to be a storm issue, it's a squall issue. And I read with interest your 62 pounds thrust comment, I see that 3.5 mercury is 90 pounds thrust.

So the 3.5 is probably the sensible choice, really, and I'm probably overly worried about weather considering the boat. Especially as it drops down a weight and price category.

I think you've "talked" me into the 3.5 20". (given me useful information that causes me to rethink my assumptions rather).

I came across a formula for outboard motor sizing which is displacement/550, giving the Typhoon a 3.6hp need. FWIW
charlesaf3
Posts: 20
Joined: Apr 12th, '22, 10:39

Re: 25" or 20" Outboard for Typhoon

Post by charlesaf3 »

So I asked around, was told 3.5 will be fine, and looks like I'll have to get a 5hp.

Why? No reverse on the 3.5. Totally impractical for my docking situation, and anyone in a slip I'd think. I've done full 360 no reverse motors before, and the were a PITA. So 5 mercury it is it would appear.
User avatar
wikakaru
Posts: 837
Joined: Jan 13th, '18, 16:19
Location: 1980 Typhoon #1697 "Dory"; 1981 CD22 #41 "Arietta"

Re: 25" or 20" Outboard for Typhoon

Post by wikakaru »

charlesaf3 wrote:I came across a formula for outboard motor sizing which is displacement/550, giving the Typhoon a 3.6hp need. FWIW
Here's a rule of thumb that has been around since the middle of the last century that I find instructive:

• To propel a vessel at its S/L 1, allow 1 hp per ton.
• To propel a vessel at hull speed, allow 2 hp per ton.
• For very heavy cruisers with blunt ends, allow 3 hp per ton.

The Displacement/550 formula you reference is basically 4 HP per British "long" ton, or 3.6 HP per American "short" ton, which is a pretty good number to use for an engine that will push a boat to hull speed with some reserve power leftover. (For long-time board readers who are sensing deja vu, I have posted about this before. Check out this thread: https://www.capedory.org/board/viewtopi ... =1&t=38370)

Most boat designers today would probably consider it crazy to install an engine that doesn't push a boat at least up to its hull speed, and ideally the engine should have the power to move the boat at hull speed even against adverse wind and sea conditions. However, when engines were first fitted to sailboats they were considered "auxiliary" propulsion, and made small. Nowadays, most "sailboats" are really powerboats, and it is the sails that are the "auxiliary" form of propulsion. So it seems obvious to say that engine size in sailboats has changed a lot over the years. Just as an example, the Cape Dory 25D (5,120 lbs., 8 HP) had 3.1 HP/ton, while the 2022 Cruising World Boat of the Year - Pocket Cruiser winner, the Beneteau First 27 (3,747 lbs.), has 8.0 HP/ton.

The Yamaha 2.5 on my Typhoon (2,000 lbs.) provides 2.5 HP/ton, which I have said is just barely enough to push the boat to hull speed. For my purposes it is just fine. The Tohatsu 6 on my CD22 (3,200 lbs.) provides 3.75 HP/ton and pushes the boat beyond hull speed with power to spare, which is about right for the way I use the 22 when I want to have an engine on it. (I usually sail without an engine.) I don't think most Typhoon owners will go wrong with any outboard in the 3.5-5 HP range.
charlesaf3 wrote:So I asked around, was told 3.5 will be fine, and looks like I'll have to get a 5hp.

Why? No reverse on the 3.5. Totally impractical for my docking situation, and anyone in a slip I'd think. I've done full 360 no reverse motors before, and the were a PITA. So 5 mercury it is it would appear.
I actually like the 360 rotation of the Yamaha 2.5 on my Typhoon, which as a F-N shifter, but that's because I use it to back out of a really tight slip. The 360 degree rotation acts like a stern thruster and I can pivot the boat on its centerline and avoid the bulkhead behind my boat and the dock lines for the floating bathroom in the slip next to me. Here's a Google Earth photo of my slip that shows why I like a pivoting outboard:
Marina.jpg
If you have more of a need for braking than for pivoting when you maneuver your Typhoon, I can see where the lack of a reverse gear could be a problem. When you swing the outboard around to the "reverse" position while it is in gear you get some side thrust which makes the boat slew around, and having to take the outboard out of gear, pivot it 180 degrees, then put it back in gear just takes too long when docking. Personally, I use an after spring line led from my sheet winch to brake the momentum of the boat when docking (see http://www.capedory.org/board/viewtopic.php?f=1&t=38540), so reverse gear isn't something that's important to me on my Typhoon. And, of course, for those who have any of the Cape Dory designs that have an outboard well, not having a reverse gear is just a bad idea.

Anyway, that's a REALLY long winded way of saying you won't go wrong with either of the two outboards you are considering, but they each offer a different set of features.

Smooth sailing,

Jim
You do not have the required permissions to view the files attached to this post.
s2sailorlis
Posts: 384
Joined: Apr 9th, '14, 18:39
Location: 1984 Cape Dory 22

Re: 25" or 20" Outboard for Typhoon

Post by s2sailorlis »

FWIW, Merc warranty is shorter than Tohatsu. Tohatsu rep told me the Mercs are same as Tohatsu. Just a data point.
______________
Rick
1984 CD22

Excuse auto-correct typos courtesy of iOS...or simply lazy typing
Post Reply