Engine size questions oday 25

[Johnkent]

I have several questions about what engine size to buy for our boat, both horsepower, length and weight.
Horse power: We have a oday 25 and live and sail on the Chesapeake Bay, so yes currents, tides & swells. From previous posts on this site it sounds like for my conditions a 9.9 would be best, that's what we have now. Having just said that, the engine place up the road is getting rid of their Hondas and they have a new 8hp 4 stoke power thrust (2001 never used) for $999 with 5 year warranty. However a good sale is not anything if it's the wrong engine. Thoughts?
Length: I currently have an Evinrude and according to how I've been taught to measure for shaft length, mine is measuring 22". The same engine place has yamaha's both 20" and 25". What is the ideal length for an oday 25. I would not want anything shorter than what I currently have as it does pop in and out with swells. At the same time I can't pull it all the way out of the water once underway, the top of the prop is still underwater which is not really an issue as we're not racers.
Weight: I know most are going to say stay with a 2 stroke, but I've had my share of bad luck with used engines and have paid more in service than what a new engine would cost for two different engine now, and we're new-bees so there's the confidence issue with new vs used. The Yamaha 9.9 that I'm looking at is right at 100 lbs, too much?
Thank you,
Kent

 

[sPk]

I have several questions about what engine size to buy for our boat, both horsepower, length and weight.
Horse power: We have a oday 25 and live and sail on the Chesapeake Bay, so yes currents, tides & swells. From previous posts on this site it sounds like for my conditions a 9.9 would be best, that's what we have now. Having just said that, the engine place up the road is getting rid of their Hondas and they have a new 8hp 4 stoke power thrust (2001 never used) for $999 with 5 year warranty. However a good sale is not anything if it's the wrong engine. Thoughts?
Length: I currently have an Evinrude and according to how I've been taught to measure for shaft length, mine is measuring 22". The same engine place has yamaha's both 20" and 25". What is the ideal length for an oday 25. I would not want anything shorter than what I currently have as it does pop in and out with swells. At the same time I can't pull it all the way out of the water once underway, the top of the prop is still underwater which is not really an issue as we're not racers.
Weight: I know most are going to say stay with a 2 stroke, but I've had my share of bad luck with used engines and have paid more in service than what a new engine would cost for two different engine now, and we're new-bees so there's the confidence issue with new vs used. The Yamaha 9.9 that I'm looking at is right at 100 lbs, too much?
Thank you,
Kent

A couple years ago I purchased a new extra long shaft Tohatsu 9.9hp 4-stroke to replacing my 1980 Johnson 7.5hp 2 stroke that was becoming unreliable. It was a major project. Due to the additional weight, the transom needed to be reinforced , a new mount purchased and a new wedge created. The engine is louder and vibrates more on most settings above idle. But it is more reliable and much more powerful. Even in Lake Superior, I rarely have to have it more than about 20% or 30% throttle.
sPk

 

[Brian S]

Shaft length should be as long as you can get, to prevent ventilation in rough conditions. I expect with short, steep chop common on the Cheasapeake, 25" would help prevent ventilation.

Also, most small outboards are sold for small jon boats, which need higher pitch props to get up on plane. This is totally the wrong prop for a sailboat that goes @5-6 knots displacement hull speed. Most Sailpro-style models may have a 4 blade, low pitch, "high thrust" prop standard, but not the others. I would expect if you went with that Honda, you'd want them to swap the stock prop for a high thrust prop.

On the other hand, if you've got a reliable 9.9 with high thrust prop now, why would you want to change? Going from a 2 stroke to a 4 stroke would give you better fuel economy. Also, going from a motor without charging circuit, you might go with the Honda if it had charging. Likewise, electric start. Otherwise, older 2 strokes tend to keep on keepin' on.

I have heard a few horror stories with Hondas, but then again, I've heard the same about smaller Nissan/Tohatsu/Mercury, especially low speed idle when the jet is continually clogged. Also recently found the smaller Evinrudes are also Tohatsu-made, according to Wikipedia.

 

[Ward H]

Hi Josh,
My Yamaha T9.9 High Thrust XL Shaft (25") pushes our O'day 25 into 20+ knots of wind with 3 to 4' chop at hull speed at half throttle. Prop stays in the water in these conditions.
I have power tilt so I never lift the mount but if I did with the motor tilted down, the prop would still be in the water but not enough to ensure good water pick up.
If I didn't have the power tilt, I would have to raise, then tilt the OB up to get it all the way out of the water.
With the high freeboard of the 25, I would not go with a shorter OB because to mount it so the prop is low enough, you need the extra length so the OB head is high enough to reach. Mine probably could be a couple inches higher but that is the way it was when I bought it.
Our OB weighs 115lbs. Without the power tilt I believe it would be 105 lbs.

I have seen O'day 25 specs that list 10hp as max and some list 15hp as max.

I have a receipt for my original Yamaha T9.9 from when it was bought in 2002. It is mounted on a bracket that is bolted flat to the transom. There is a large piece of 1/2 starboard on the outside of the transom and a matching piece on the inside as well, to reinforce the mount. Not sure if there was a hump that was removed or not.
I have no evidence of flex on the transom.

My other thought is try to get the gear shift mounted on the tiller near the throttle, not on the OB head itself. That will save you from having to lean way over to shift.

BTW, that 2002 model had electric choke which gave me fits. I bought the one I talk about above last season.

I will try to post some photos of my bracket a bit later.

 

[Johnkent]

Thanks for the replies, all good stuff. Yeah I'm really up in the air on this one, I feel because of the weight, a 2 stroke would be a better fit, it's just that I've been burned twice with 2 stokes so I'm very gun-shy. By the way, when I asked the local dealer why they were discontinuing Hondas he said because they are more expensive to work on. He pop the hood on a yamaha and the oil filter was right there, he went to the Honda and explained what all was involved in replacing the oil filter, vastly different.

 

[Johnkent]

Thanks Ward, is your 9.9 a 4 stroke? Great info by the way. As for the controls, I went with a PowerTiller control system and it works well. Now I can actually be looking forward while approaching the dock. Whatever engine I buy, it will have to be compatible with this system. It's too good not too. The guy who developed the device is not really into selling this product, that's my take, and he was talking about a redesign and going from the current material, aluminum to some kind of ABS plastic. I wanted the aluminum one, which he's not selling so I found a new one on ebay. The controls are mounted to my tiller. Here's a couple of photos of my current set up, it may evolve to something else but for now it's working. I changed out from zip ties to hose clamps. ok I could not figure out how to post a photo. I will research and post later.

 

[Johnkent]

ok I see you said 115lbs so yes I'm going to assume it is a 4 stroke

 

[Johnkent]

Just found out I have a 20" shaft which as I said, pops in and out of the water in fairly small swells. This might be a cause for burning out the impeller which has happened since I've owned the engine. So thanks for the 25" suggestion, I love forums.

 

[Ward H]

John (sorry about the wrong name)

Yep a 4 stroke. Quieter, cleaner, less smell and no mixing the fuel. I am lucky to be near an airport so I can get aviation gas so no ethanol worries either.

I attached photos showing the bracket on the transom and the backing plate. The only time I need to raise the bracket is if I want to do something on the OB with it tilted down. Otherwise the bracket stays down and I just tilt the OB.
Plus, you can't buy a new 2 stroke unless it is new old stock.

Docking was like landing on an aircraft carrier for me until I installed a bridal rope system which helps to catch me coming in and keep me off the dock and neighbor boats. I use both the rudder and OB to steer so can just creep in and turn pretty sharp.

I find attaching photos easiest by going to "Advanced", then click on the camera icon. Photos need to be under 100kb or something like that.

Let us know what you decide.

 

[korchinskyp]

I believe the wedge is there so that the motor can be tited and still clear the transom.
Also without the wedge I would expect the bracket handle to also be too close to the transom. I looked at an O'Day 25 with a new Mercury 8 H.P. atached to the original wedge and the transom was distorted. Bracket manufacturers tell you not to put four stroke engines on those brackets made for two stroke engines. It's not just the extra weight but also the torque developed in the new four stroke engines. I don't believe there are any brackets made for a four stroke that will fit on existing older wedges.

 

[Ward H]

I agree. I wouldn't put a 9.9 hp 4 stroke on a wedge. Just not made for it. At least not on my boat. The motor bracket set up was one of things I liked when I was looking at buying my 25.

 

[Johnkent]

Thanks Ward, do you have a link to the bracket that you used? Thanks for helping me with my homework. Will try to send photo of my powertiller. Like I said, I replaced the zip-ties with ss hose clamps. It did the trick.

 

[Ward H]

That's an OMC bracket. Was on the boat when I got it. Not made anymore from what I hear. If I was looking for a new one I would look at Garelick brackets.
That Power Tiller looks interesting.

 

[Johnkent]

Yes I like the powertiller but he can be a hard fellow to reach. Until now, everything has been hand fabricated but as I mentioned, he's looking at a redesign to lower the cost of manufacturing. He said he wants to do this so he can keep his price in line with his competitors. Funny thing is, I have searched the net pretty extensively and can not find another product out there like it. If you try to contact him from his site, http://powertiller.com you'll get a auto-response with a phone number, I think he tends to answer his phone. The unit I have is very good quality. The last time I spoke with him, he said he still had a few of his older units (like mine) in stock but I could not get him to sell me one, he kept putting it off. I'm not sure his heart is in the business, I think it's a solid idea that perhaps he should sell and let someone else do the manufacturing.
There is not alot throw in the throttle but that might be my engine, it's a direct correlation. It just means mircro moves. However the strength is really having gear control on the tiller, and for new-bees like my wife and myself, it's tremendous. The first time we came into our dock… it was not pretty, the first time with the powertiller, a perfect 10 point landing. Because as you guys know, you're kinda half hanging over the transom to shift. (I'm sounding like a commercial) Some people add the tiller to engine cable system so that the engine turns with your tiller. I did not do this but the video is pretty darn expressive.

When you guys are talking about the wedge, I assume this (photo) is what your'e talking about. And I'm assuming the problem is the foot-print size is too small for the weight, you need more displacement i.e.: your bracket.

Thanks

 

[Johnkent]

Hey Ward, so when I went to the bracket site you suggested and saw an image I realized that's what I have on my boat, (previous photo). Although the makers mark is covered up I'm sure it's the same thing, and mine works well. So don't need a new bracket, I just need to change out the wedge with a large mounting plate of some kind. And it looks like the bracket will change angle to compensate for following the transom angle.

 

[Johnkent]

Hey Ward, I'd like to say this is the last time I'm going to bug you but it probably wont be. In the photo you posted, in looking at the mounting on your transom, both inside and out, does that material they used look like the same material used for a commercial cutting board? We have a heavy duty cutting board on the dock for cleaning fish, the sun has not affected it and I'm sure it's more than strong enough to use. Don't you think I could use the same type of material to for my new mount, both inside and out? thanks again
kent

 

[Brian S]

I have seen some folks build up a new fiberglass wedge. Somewhere on this site, I think.

I would not use cutting board. Or Starboard, for a motor backing plate. Starboard is high density polyethylene (HDPE) or ultra-high density polyethylene. It has a tendency to compress under load, and walk or creep. If I had to build up a transom, I'd probably pony up for some G10 board, and glue it in place with epoxy. It is low resin to glass ratio fiberglass board.

Brian

Hey Ward, I'd like to say this is the last time I'm going to bug you but it probably wont be. In the photo you posted, in looking at the mounting on your transom, both inside and out, does that material they used look like the same material used for a commercial cutting board? We have a heavy duty cutting board on the dock for cleaning fish, the sun has not affected it and I'm sure it's more than strong enough to use. Don't you think I could use the same type of material to for my new mount, both inside and out? thanks again
kent

 

[sPk]

I have seen some folks build up a new fiberglass wedge. Somewhere on this site, I think.

I would not use cutting board. Or Starboard, for a motor backing plate. Starboard is high density polyethylene (HDPE) or ultra-high density polyethylene. It has a tendency to compress under load, and walk or creep. If I had to build up a transom, I'd probably pony up for some G10 board, and glue it in place with epoxy. It is low resin to glass ratio fiberglass board.

Brian

I tried mounting the engine without the wedge and the 4-stroke Garelick mount but ended up making a custom wedge or actually wedges out of wood/fiberglass. The angles and design boggled my mind even though I started from someone else's rough wedge design. Having the shift on the tiller would be nice addition/option. I do like having electric start and charging but I think I may have been able to get by with smaller HP motor but I don't think there was much of a weight savings so I opted for 9.9HP.

http://www.garelick.com/Aluminum-Auxiliary-Motor-Bracket-For-4-Stroke-Motors

 

[Ward H]

sPk,
Nice looking job. What mount model # did you use?

Brian,
I just bought a sheet of starboard to play around with. Made winch pads and a pad for my new line clutch.
It sure looks like what was used under my motor mount but I don't know for sure.

John,
I looked at the Garelick site. I don't think that is what you have on your boat. Yours looks similar but I don't think it is a Garelick for 4 stroke.

As to what material to use, I don't know and would defer to Brian.

 

[Brian S]

As to what material to use, I don't know and would defer to Brian.

I've been trying to figure out what Starboard is, and after looking at some of it, concluded it was UHMPE. Can't get any answers from the website. I've been around polyethylene enough with my kayaks, I couldn't imagine using it for much structurally. And there's Dyneema, which is UHMPE line, if memory serves. Waxy stuff, not much sticks to it. And slippery.

It was MaineSail who said he wouldn't use Starboard for a backing plate. I'll parrot him for anything, guys knows his stuff, and if it doesn't work, he'll call it out!

The guys who build the Left Coast Dart won't use any wood anywhere in the boat, except for trim pieces. They use all foam cores, and G10 where extra strength or through bolting is required. It's all vacuum bagged and infused resin, and I think they aren't messing around with inferior construction methods.