CONTINUOUSWAVE

I recently acquired a 1999 18 Dauntless. I have purchased a SUZUKI 140. What is the correct propeller to purchase?

I may buy a 14 x 20, a 14 x 21, or maybe a 14 x 22.

—Rick

I would start with a Suzuki stainless 14 x 22. The engine should be mounted "two-holes-up" meaning the top bolts are in the third hole down from the top.

I owned a 1999 Dauntless 18 for ten years. It was powered by a 1998 Evinrude 150 Ocean Pro carburetor engine set on a jack plate. I used a 17-pitch four-bladed propeller.


Fig. 1. The previously owned 1999 Dauntless 18 boat with a 1998 Evinrude 150 carburetor engine.

I now own a 2003 190 Nantucket powered by a 2016 Suzuki DF 140a, so I have experience with both the hull and engine, just not together.


Fig. 2. The currently owned 2003 190 Nantucket powered by a 2016 Suzuki DF 140a

On the DF140a engine [on the 190 NANTUCKET--a different boat than the boat under discussion in this thread] I am using a Suzuki 20-pitch three-bladed propeller. This 20-pitch three-bladed propeller gives me a good mix between [acceleration from a standing start at full throttle] and cruising speed.

For the [18 DAUNTLESS boat under discussion in this thread] I suggest starting with a Suzuki 20-pitch three-bladed propeller on the Suzuki DF140 engine.

I also recommend the Suzuki DF140 engine be mounted as high possible. The 18 DAUNTLESS boat hull has a notch in the lower transom that will enable you to mount the engine high--at least that’s what I was told by a Boston Whaler representative at a boat show.

CONTENDER--you picked a good engine for an 18 DAUNTLESS. The 18 DAUNTLESS has a weight sensitive stern. When I had my 18 Dauntless, I targeted the [Suzuki 140a] engine for a re-power.

Very interested in the performance numbers of the Suzuki 140 hp on your Nantucket 190 and Dauntless 18.

I’m thinking of repowering my Outrage 18 with the Suzuki 140.

Con

[Some data about a different boat than the boat under discussion in this thread is given here--Moderator]

The 190 Nantucket hull weight is 2050-lbs and fuel capacity is 65 gallons. Mine also has a T-Top which adds more weight.

With a full tank and four adults plus one basset hound, I can cruise the 190 NANTUCKET at a boat speed of 25-nautical-miles-per-hour [or 28.75-MPH] and [the SUZUKI DF140a engine] speed is 4400-RPM.

The full-throttle engine speed of the SUZUKI DF140a engine is 6,200-RPM and boat speed for the 190 NANTUCKET is 40-nautical-miles-per-hour [or 46-MPH]

[Moderator's note: converted all boat speeds in nautical-miles-per-hour to statute-miles-per-hour. The distance "nautical mile" is used when a ship is "at sea."]

This SUZUKI DF140a engine likes to run at high RPM. I would think the SUZUKI DF140a would be a great match for your classic OUTRAGE 18 boat.

All good to know.
Thanks, Con

ASIDE: SUZUKI has introduced a new model 140-HP engine, the DF140BG. The prior model DF140a is still available.

Comparing propeller pitch with different engines will be difficult if the gear ratio is not identical. The SUZUKI four-stroke-power-cycle engines tend to use higher numerical gear ratios which reduce the propeller shaft speed relative to the engine crankshaft speed, but increase the torque.

Predicting the optimum propeller is really difficult. Optimizing the propeller can really only be done by actual on-the-water testing with the actual boat, the actual engine, in the normal loading, and on the normal water and temperatures in which the boat will be used. Many factors will affect performance and influence propeller selection.

When buying a new engine that is not part of a boat-engine package, the dealer selling the loose engine usually can provide assistance in selecting a propeller, with the expectation--of course--that you buy the propeller from that dealer. This may result in a slightly higher cost. But being able to sea trial and test several propellers with the engine-seller will usually be worth much more than the cost increase from buying from the dealer.

Mount it as high as possible, not 2 holes up. Suzukis like to be mounted high. I would start with the 22"