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Hi All

We had a great day of motoring around in warm, late summer conditions on the Ottawa River. Its only my 4th time out motoring on the 26M equipped with a 2010 Suzuki DF60A. I put a new prop on it due to the condition of the one that came with the boat - a Suzuki 11 5/8 x 12 3 blade. I based the size on what was on the boat when I bought it and a bit of reading on this website and others.

With water ballast in, mast up and sails on, two 6 tanks of fuel and 3 people on board, the boat will do around 5 knots at 4000 rpm and max out at 12 knots at WOT at 5500 rpm. It cruises happily enough at 3500 rpm that gives about 4 knots (all speeds provided by the Ray Marine system and they bobble around by + or - 0.2-0.4 knots or so).

Those RPMs and knots are sorta what I expected for a ballasted boat with some people on board. However, one other thing I've noticed is the engine gets a deep bass rumble and vibration to it as it approaches WOT - is this cavitation or ventilation problem? The propellor seems to be not very far from the surface even in the straight up and down position. It does not seem capable of lifting the bow of the boat - the engine lifts and the prop gets closer to the surface when I adjust the trim so it seems to be getting into more aerated water (?). The trim level indicator seems to show a level boat but from my perspective from the helm the bow seems raised. If I try to raise it more (to see if I can ease into a plane) the engine just gets closer to the surface and makes more noise and vibration and loses thrust (or so it seems). It does not sound or feel good at those speeds.

As I'm not going to change an engine to try to get a prop deeper into the water (expense plus a bigger risk on a river) would adding an anti-ventilation plate to the lower unit help? Or is this just the nature of the beast?

Instead of adjusting the motor, try placing more weight forward. You might experiment with this by having someone moving forward, and sitting at the bow. See how the boat responds.

Hi 45Plus+!

I suspect that NiceAft is on to something with the weight shifting idea.

We have a Mac26X with a 2021 Suzuki DF60AV which when the boat is bare bones empty will give us nearly 20 mph.
Loaded as we are for cruising with 24 gallons of fuel, two adults and all our cruising stuff and a hull that needs a good wash after sitting in our warm summer of brackish tidal estuaries here in South Carolina we still get about 12 to 15 mph. We do have a fairly balanced boat fore and aft…( we list a bit to Port as the dual batteries and A/C unit are both on that side …. eventually I’ll get that sorted) which helps a lot getting up on plane.

We found that if the boat is loaded too far aft it doesn’t like getting on plane. To help it along one of us would go forward into the cabin to the V-berth and the bow would level down allowing the boat to stabilize on plane which added about 4 to 5 mph to our speeds.

When we are actually on a distance cruising trip we make it a point to have a clean hull and a balanced boat all around. This helps a lot with getting up on plane and stabilizing.

As a starting point (which is what we did), If you can, try and look how your boat sits statically in calm water vs the waterline boot stripe.if there is a variation fore vs aft and port vs starboard then see if you can adjust things internally or where you have people seated in the cockpit to even things out.

When we travel with just two adults we find it best with the the helm seat and starboard bench occupied. Particularly if the passenger is seated on the forward portion of the starboard bench.

Best Regards,
Over Easy

It might help to post a photo of your engine mount location. Also, maybe a video of this cavitation you are experiencing.

I don't remember what size prop I have on my DF70, but at 3,000RPM we get about 7mph. I usually cruise at about 2500-2800 which is just over 6mph.
This is heavy ballast and 24gal of fuel and 3 people and the bottom is dirty. At WOT, I never reach 5,000RPM (only about 4900) and get about 16-18mph fully loaded. I'm probably still overpropped, but I rarely run at WOT anyway.

Something doesn't seem right about your setup.

My boat never gets on full plane. The bow always lifts up which squats the transom deeper. As mentioned, simply having a crew member go up into the v-berth can get the bow down and up more on plane.

The "red line" in this photo is where I remember the top of the water surface at WOT. Which should also be in line with the bottom of your transom.

Timely thread, after battling confused waves all day Vicky went down into the center aisle of the cabin just as I cranked the throttle over 3,000rpm and it felt like the boat was on rails, tight on it’s heading running 7.5 - 8 knots. It didn’t occur to me it was her being in the center of the cabin but that perfectly tracks to when the steering finally found a groove.

tuxonpup wrote: ↑Mon Sep 01, 2025 7:54 am Timely thread, after battling confused waves all day Vicky went down into the center aisle of the cabin just as I cranked the throttle over 3,000rpm and it felt like the boat was on rails, tight on it’s heading running 7.5 - 8 knots. It didn’t occur to me it was her being in the center of the cabin but that perfectly tracks to when the steering finally found a groove.

Have her go forward more. That's the ONLY way I can get my boat on plane. Or partial plane or whatever it is.

Yes, you can feel it lift up.

Thanks for the replies. I will be going out in the next day or two and will try shifting weight forward - though I have to admit it seems counter intuitive if the engine seems to have trouble raising the bow. But as a number of replies noted, perhaps having too much weight aft means when the engine does try to raise the bow, the stern hunkers down instead. I will try getting one of my guests (can't call them "ballast" can I ) up towards the V berth and see what happens. I will try to get a picture and video of whats going on around the engine as well - engine position and water level wise.

45Plus+ wrote: ↑Mon Sep 01, 2025 11:12 am Thanks for the replies. I will be going out in the next day or two and will try shifting weight forward - though I have to admit it seems counter intuitive if the engine seems to have trouble raising the bow. But as a number of replies noted, perhaps having too much weight aft means when the engine does try to raise the bow, the stern hunkers down instead. I will try getting one of my guests (can't call them "ballast" can I ) up towards the V berth and see what happens. I will try to get a picture and video of whats going on around the engine as well - engine position and water level wise.

Yeah, I’m not calling Vicky ballast… we’ll go with ‘warp drive Ms. Scotty!’

Passenger=Moveable Ballast
(Sounds a lot better than "rail meat")

When I posted about moving someone forward to the bow, I should have mentioned this warning in the manual.

Yah, I saw that in the how-to guide that came with the boat. Its good advice on any boat but particularly the Mac 26 Ms and Xs. That said, the boat seems to do fine with two adults sitting up near the forward hatch while motoring along at 4-5 knots in little wind and little wave. Same goes with going down below while underway. Being on the foredeck in more lively conditions or sailing would not be contemplated except I really had to. I imagine you could reach a good deal of anything that might need adjustment or fixing from the forward hatch - or hopping out on deck near it. I hope I never have to be in a situation where I would have to but its best to have contemplated plan Bs and Cs.

You can move most of your body weight well into the bow while staying in the v-berth.

With my 40hp engine I can't ever get to a true planing configuration but having my younger brother (who outweighs me by 60 pounds) lean up into the v-berth made a noticeable difference. Even a heavily loaded boat with a 40hp will get well above hull speed. Your 60hp should be able to get pretty close to a full "plane" if you are not heavily loaded.

Sails down, keel and rudders up, ballast out (my preference under power) and you should be (by far) the fastest sailboat on the lake. Be careful during the transition from displacement to planing. The steering can get a little "tentative". It will get better once you get past that spot.

With water ballast in, mast up and sails on, two 6 tanks of fuel and 3 people on board, the boat will do around 5 knots at 4000 rpm and max out at 12 knots at WOT at 5500 rpm. It cruises happily enough at 3500 rpm that gives about 4 knots (all speeds provided by the Ray Marine system and they bobble around by + or - 0.2-0.4 knots or so).

Getting back to your original question, I think you have something "off" in your setup. Similarly loaded with a 40hp engine I do 10 knots at 4000 RPM and at 5000 (my top-end) I'm doing 14 knots. At 4 knots I'm turning over less than 1500 RPM. Your numbers should be a lot better than mine.

45Plus+ wrote: ↑Tue Sep 02, 2025 6:40 am Yah, I saw that in the how-to guide that came with the boat. Its good advice on any boat but particularly the Mac 26 Ms and Xs. That said, the boat seems to do fine with two adults sitting up near the forward hatch while motoring along at 4-5 knots in little wind and little wave. Same goes with going down below while underway. Being on the foredeck in more lively conditions or sailing would not be contemplated except I really had to. I imagine you could reach a good deal of anything that might need adjustment or fixing from the forward hatch - or hopping out on deck near it. I hope I never have to be in a situation where I would have to but its best to have contemplated plan Bs and Cs.

I've been on the foredeck in very rough conditions. You don't want to be there (and you don't have to).

It's been said that good decisions come from experience and experience comes from bad decisions (or something like that). After a couple of very scary trips to the foredeck to strike the jib I realized that the jib could be pulled down while standing in the forward hatch. Two lessons learned: Going on deck was not needed and strike the jib (and reef) sooner. Later I added a down-haul and now I don't even need to leave the cockpit. I've not been on the foredeck in bad weather since.

The other place you don't want to be in bad weather is the cabin top in rough conditions, solo, at night trying to drop the main. You can't reach it through the companionway. Been there. Done that. Got the rain-soaked t-shirt. A down-haul for the main as well as a proper harness and jack lines are on the short list of mods before I do another solo overnight sail in the Gulf.

A Dear Friend who unfortunately left this mortal coil too soon last year shared a very good technique with me for going up on the top deck.
See I have a pretty game knee and a similar back so even in good conditions it’s not something I can do with any grace or fluidity.
The mere thought of having to go forward on deck in stable conditions, never mind adverse ones, was a concern… such as having to drop anchor to safely weather a storm.

He shared with me his technique of clipping a safety tag line to either side of my safety harness to either of the life lines on the cabin deck.each tag line is long enough to allow me to move to either side comfortably. To get past the mast up to the bow is a simple process of un clipping on tag line at a time to get past the fwd Stanchion posts. This simple technique was a game changer for me in stability but in confidence.

Best Regards,
Over Easy

This year I FINALLY installed lazy jacks and a looped main halyard so I don't have to go up on deck to hoist sails.
Being able to avoid the foredeck in bouncy situations is a game changer.

What I wish was my dodger had a handle. I grab the dodger as a handle now and then the shrouds.
When the mast is down and dodger not installed, I hate walking up on deck as there isn't much to hold onto.