26X Repower Questions

A forum for discussing boat or trailer repairs or modifications that you have made or are considering.
macowneril2015
Engineer
Posts: 188
Joined: Tue Nov 10, 2015 5:51 pm
Sailboat: MacGregor 26X
Location: Downtown Chicago, 2001 26X, 2001 50 Hp Nissan (NS50D2)

26X Repower Questions

Post by macowneril2015 »

I have decided to repower due to the stubbornness to tune and difficulty of getting parts for my old 50 HP Nissan. I was leaning towards going with a Mercury as that seems to be the only outboard engine that has dealers and service representatives readily available in the Chicago Metro area. Is there any suggestions as I assume I should stick with the :macx: recommendation of a 50 HP outboard but are there other nuances like prop size/ pitch, shaft length or any suggested models? I am green at the whole repowering and scrubbing the forum I see a lot of different opinions and a preferential lean towards other manufacturers. Any help is appreciated.
User avatar
Jimmyt
Admiral
Posts: 3166
Joined: Sat Jul 18, 2015 9:52 am
Sailboat: MacGregor 26M
Location: Mobile AL 2013 26M, 60 Etec

Re: 26X Repower Questions

Post by Jimmyt »

What horsepower to buy? Something between 10 and 115 hp, based on who you're asking. I've got a 60hp Etec that will push my boat right at 20 mph with 4 adults and no ballast (mast and rigging in place). If you want to plane, probably 60 hp should be your minimum. If you want to ski behind it, maybe a 70-90 hp selection. At the upper end (beyond 70hp), most folks are putting in some form of transom reinforcement. I'm stating what others have done - I'm not recommending anything over 60hp, because that seems to be where the Macgregor dealers stopped. But, lots of our members have 90's and above, and have run them successfully for many years. You may be somewhat limited by what the dealer is willing to mount on the boat.

I would buy a motor that had readily-available, honest, factory service near you. I think Mercury makes a pretty good outboard. I would want the dealer to service the outboard until the warranty runs out. But, that's just me.

The shaft length is generally determined by your transom height where the motor is mounted. Here's a fairly good discussion that includes some sailboat thoughts (read to end).

https://towers4boats.com/how-to-measure ... ft-length/

Start with the dealer's recommended prop for a pontoon boat of equal weight. Talk to them about loaning you a prop or two to test on the boat - to get zero' in. Never hurts to ask. Can't really even start guessing at props until you've picked a horsepower, lower unit gear ratio, and max rpm.
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River
leefrankpierce
Engineer
Posts: 140
Joined: Fri Oct 06, 2017 5:13 am
Sailboat: MacGregor 26X
Location: Dallas Ft-Worth Texas

Re: 26X Repower Questions

Post by leefrankpierce »

While we all have our opinions, I went with an old carbed mix your own gas johnson/evenrude V4 120hp.
Common as dirt, everyone knows how to work on it, it fit great.
I think the angle of the prop in its most downward position is limiting my performance.
I probably need to add wedges in top to get enough down.
Downsides = smokes, eats more fuel than the 50 hp.
So if I have plenty of $ I would probably stay with a 4 stroke.
Clearance between the seat and the engine = the biggest factor.
Do not get something too tall.
26X in Dallas Fort-Worth area Texas
Slip at Eagle Mountain Lake
:macx:
User avatar
Jimmyt
Admiral
Posts: 3166
Joined: Sat Jul 18, 2015 9:52 am
Sailboat: MacGregor 26M
Location: Mobile AL 2013 26M, 60 Etec

Re: 26X Repower Questions

Post by Jimmyt »

How does it run with that 120 on the stern? Have you measured your top speed?
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River
leefrankpierce
Engineer
Posts: 140
Joined: Fri Oct 06, 2017 5:13 am
Sailboat: MacGregor 26X
Location: Dallas Ft-Worth Texas

Re: 26X Repower Questions

Post by leefrankpierce »

I put it in from a trailer so I knew the ballast was empty, with three big guys we were as fast as I thought safe for the motor, but it was dark and I did not check the actual speed. I did go sit on the bow while my friend drove and it felt on plane and fast. Likely it needed the weight up front.
I think I need more down trim. With my wife and I sitting in the back, and all the stuff we add (microwave, enough throw pillows that I can not find the V-birth, etc...) Full ballast, I measure 20mph with bow high so I do not think I am getting on plane but just plowing.
Point being, I do not think I am giving it a fair shake.
I did open the valve once, it did get faster after about 5 minutes, but I still do not think I am on plane, have no idea if the ballast empties.
I will try to get my wedges installed to give more down and then report back again.

It feels like what this guy is doing (not me)
26X in Dallas Fort-Worth area Texas
Slip at Eagle Mountain Lake
:macx:
User avatar
Jimmyt
Admiral
Posts: 3166
Joined: Sat Jul 18, 2015 9:52 am
Sailboat: MacGregor 26M
Location: Mobile AL 2013 26M, 60 Etec

Re: 26X Repower Questions

Post by Jimmyt »

If you are going 20mph, your ballast was draining. It will drain at much lower speed than that. Just fast enough for the water to break away from the stern is all it takes.

20mph with full ballast and loaded is pretty good.

Check your manual, but if you’re a pretty big guy, you probably shouldn’t be on deck, planing, with empty ballast. It’s a stability issue.

Thanks for the feedback. Probably need a prop change to optimize for your application, but seems like you have a nice setup.
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River
User avatar
Starscream
Admiral
Posts: 1388
Joined: Tue Nov 03, 2009 10:08 am
Sailboat: MacGregor 26X
Location: Montreal, Quebec. 2002 26X - Suzi DF90A

Re: 26X Repower Questions

Post by Starscream »

I'm wondering about the wedges and the down angle. I have a 90HP, with wedges, and top out around 20MPH with ballast and gear.

The boat is nose-high at full throttle, of course.

More down angle will cause some of the motor power to be lost to lifting the stern...which, ok, will lower the nose and make a plane more likely. But i feel like that's an artifical plane and I want all the motor thrust to be directly rearward. Isn't the best motor angle to have the prop thrust horizontal when at max throttle? If so, I need to lift the motor a fair amount using trim (haven't tried that) to achieve the highest forward thrust.

Is dropping the nose using wedges and down angle worth losing a component of the prop thrust to lifting the stern? I'm really not sure.
User avatar
Jimmyt
Admiral
Posts: 3166
Joined: Sat Jul 18, 2015 9:52 am
Sailboat: MacGregor 26M
Location: Mobile AL 2013 26M, 60 Etec

Re: 26X Repower Questions

Post by Jimmyt »

I’m inclined to agree with you. If our hulls didn’t have all that rocker in them, things would be radically different. It seems like the boat has to rotate up until the aft section is planing. Once you’re planing, the less hull in the water, the better. Pushing the nose down increases the wetted area, and as you pointed out, uses thrust for attitude adjustment rather than speed.
Jimmyt
P-Cub-Boo
2013 26M, Etec 60, roller Genoa, roller main
Cruising Waters: Mobile Bay, Western Shore, Fowl River
OverEasy
Admiral
Posts: 2010
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26X Repower Questions

Post by OverEasy »

Hi LeeFrankPierce!

Do you have any numbers on your engine weight?
How much fuel are you carrying?
Do you carry much gear in the aft berth?

Best Regards
Over Easy 😎😎🐩🐈
leefrankpierce
Engineer
Posts: 140
Joined: Fri Oct 06, 2017 5:13 am
Sailboat: MacGregor 26X
Location: Dallas Ft-Worth Texas

Re: 26X Repower Questions

Post by leefrankpierce »

OverEasy wrote: Fri Mar 31, 2023 11:06 am Hi LeeFrankPierce!

Do you have any numbers on your engine weight?
How much fuel are you carrying?
Do you carry much gear in the aft berth?

Best Regards
Over Easy 😎😎🐩🐈
Have no idea how much the thing weighs, but it is not balanced like my honda 50, so I have to be careful under sail or disconnect it from the steering.
I carry 2x6 gallons, but really want to increase to 2x12 gallons.
No gear in the aft berth, other than the mast raising system.

As far as improving getting on plain.
When I had a V8 powered cabin cruiser, I used to get it on plane with the trim almost all the way down and then trim back up once on plane for better stability and speed.
So I presume I need more of the engine pushing up to get up on plane and then will tune the up trim to where the boat is happy.

Lee
26X in Dallas Fort-Worth area Texas
Slip at Eagle Mountain Lake
:macx:
OverEasy
Admiral
Posts: 2010
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26X Repower Questions

Post by OverEasy »

Hi LeeFrankPierce!

Just for reference I believe a V4 Johnson 120hp is built on a 2.0 liter loop charged block and weighs approximately 365 lbs.
Gasoline weighs in at about 6 lbs per gallon so 12 gallons would weigh about 72 lbs.
No relevant aft cabin load weight.
So relative stern weight for your setup for fuel and engine is about 437 lbs.

For our setup with a Suzuki DF60AV 4-stroke carrying 24 gallons of fuel and about 200 lbs of cargo in the aft berth:
Engine. = 230 lbs
Fuel = 144 lbs
Aft berth cargo = 200 lbs
======================
Total = 574 lbs

For comparative reference:
We get a GPS dual directional average speed in calm water without ballast (includes two adults, portable AC and cruising gear in addition to the 200 lbs in the aft berth along with ablative bottom paint but no mast/boom/sails or rudders onboard) of approximately 24+ mph. With full ballast that drops to about 20+ mph in clam water.
While it gets up and goes the hull of a Mac26X doesn’t really plane flat but has a definite bow up orientation that flattens somewhat after transition. Now that our engine has broken in the WOT peak rpm is 5400 rpm.

It would have been my assumption that with twice the hp and nominally 137 lbs lighter your top speed would have been higher and easier to get on step as it were.

Just thinking about it…🤔

Best Regards
Over Easy 😎😎🐩🐈
Kenpool
Posts: 1
Joined: Fri Jan 26, 2018 3:51 pm
Sailboat: MacGregor 26X

Re: 26X Repower Questions

Post by Kenpool »

I have a new Mercury Pro XS 115 CT I’m installing on my 2002 26X. Not much to report yet but I can keep you posted on my progress. Another owner nearby has a Mercury 90 which is the same size and weight as mine so I’ve been able to see how his was installed.
User avatar
pitchpolehobie
First Officer
Posts: 480
Joined: Wed Dec 18, 2019 8:46 pm
Sailboat: MacGregor 26X
Location: USA, OH

Re: 26X Repower Questions

Post by pitchpolehobie »

OverEasy wrote: Sat Apr 01, 2023 12:05 am Hi LeeFrankPierce!

Just for reference I believe a V4 Johnson 120hp is built on a 2.0 liter loop charged block and weighs approximately 365 lbs.
Gasoline weighs in at about 6 lbs per gallon so 12 gallons would weigh about 72 lbs.
No relevant aft cabin load weight.
So relative stern weight for your setup for fuel and engine is about 437 lbs.

For our setup with a Suzuki DF60AV 4-stroke carrying 24 gallons of fuel and about 200 lbs of cargo in the aft berth:
Engine. = 230 lbs
Fuel = 144 lbs
Aft berth cargo = 200 lbs
======================
Total = 574 lbs

For comparative reference:
We get a GPS dual directional average speed in calm water without ballast (includes two adults, portable AC and cruising gear in addition to the 200 lbs in the aft berth along with ablative bottom paint but no mast/boom/sails or rudders onboard) of approximately 24+ mph. With full ballast that drops to about 20+ mph in clam water.
While it gets up and goes the hull of a Mac26X doesn’t really plane flat but has a definite bow up orientation that flattens somewhat after transition. Now that our engine has broken in the WOT peak rpm is 5400 rpm.

It would have been my assumption that with twice the hp and nominally 137 lbs lighter your top speed would have been higher and easier to get on step as it were.

Just thinking about it…🤔

Best Regards
Over Easy 😎😎🐩🐈
Does power trimming after reaching top speed help flatten it out any more?
2002 MacGregor 26X: Remedium
Tohatsu 25HP
Cruising Area: Inland Ohio, Lake Erie
OverEasy
Admiral
Posts: 2010
Joined: Mon Sep 28, 2020 11:16 am
Sailboat: MacGregor 26X
Location: NH & SC

Re: 26X Repower Questions

Post by OverEasy »

Nope
leefrankpierce
Engineer
Posts: 140
Joined: Fri Oct 06, 2017 5:13 am
Sailboat: MacGregor 26X
Location: Dallas Ft-Worth Texas

Re: 26X Repower Questions

Post by leefrankpierce »

Went out yesterday to verify, full of ballast I top out at 20mph.
Have no idea what my rpm is. (no gauge)

Running a Solas 2411-138-13 which is a 13.75 diameter 13 pitch prop.
Totally possible I need a different prop for speed, however not sure I want more pitch as it is as fast as I want it at idle in the marina.
Putting the numbers into the Solas prop finder, presuming 3000 lbs as a round about guess, it suggests the prop I have.

I suspect my ballast is not draining. I have vent using a tube from the front birth back to the cockpit and it might be kinked.
When I have put it on a trailer and pulled the ballast dump, it seemed like it was not venting with the water coming out in burps.
Did not care enough to go fix, so I guess I could fix and then re-try to dump my ballast.
26X in Dallas Fort-Worth area Texas
Slip at Eagle Mountain Lake
:macx:
Post Reply