1st Test Cruise of "Trawler" Upgrade to Com-Pac Suncat.

[cruz-in]

Hi All,

You may have followed my other threads as we worked thru up engining our Suncat.

Background:

While we love to sail, we wanted the ability to motor for prolonged periods with minnimal vibration and sound. We seriously looked at Ranger R21 Tug. The  diesel did not pass the noise criteria. So I got to thinking about modifing our Suncat for more prolonged motor journeys up the many creeks off the Chesapeakke Bay.


The Hardware:

1) Researched and researched motors. It seemed that the older Yamaha 6 HP were somewhat legendary for being extremely  smooth and quiet. They havee two cylinders, the F/N/R control is on the tiller, sounded perfect. Set out to find one. Using nationwide Craigslist search engines, we found one about 250 miles inland near Pittsburg PA. It was a 2006, Had only been used about 10 hours n a fresh water lake. It was really in pristine condition and for $750 it was ours. However, the beast weighed 86 pounds.

2) We were going to need a significantly beefed up motor mount with backing plate. I ordered 4 motor mounts (2 Garelicks and 2 Panthers) and for one reason or another, I found none of them suitable. Then shawn (on this site) alerted me to the Catalina Direct Motor mount. It is a thing of engineeering/manufacturing beauty. I know good engineering/manufaccturering,  my last job was chief engineer for an aircraft prototype organization. This motor mount had beautiful welds, heavy stainless steal construction, bronze bushings, I could go on  and on. Again, it is a thing of beauty. Here is a link to mount. IMHO, a bargain at $350.

https://www.catalinadirect.com/index.cfm/product/707_84/outboard-motor-mount-four-spring.cfm

3) What to do about the weeight  inbalance created by  the heavy motor and mount? I was adding about 50 poounds (above what the old motor and mount weighed)to the aft, port side,of my Suncat. I was certain I would need weight on the opposite side and well forward to balance the Suncat. To get the weight, I useed a 150 pound Sumo Water Ballast sac. Link below. I placed it on the opposite side from the  motor, forward underneath the berth. It fit perfectly. This allowed me to pump water in or out to balance the boat.

http://www.wakehouse.com/products/straight-line-sumo-sac-150-lbs.html?dfw_tracker=10071-5188&gclid=Cj0KEQjw9vi-BRCx1_GZgN7N4voBEiQAaACKVks2DrFaMfURNcBrmYO0_TR2LFSrPnkOEWBPpiBWGh0aAn3l8P8HAQ

1st test run:

Exceeded our hopes. Quiet, smooth, stable. At about 1/3 throttle we scooted along at about 5 MPH. Could easily have conversations in normal tones. Could hear the water lapping against the hull. The addeed weight (water ballast and motor)made the Suncat, an already satble boat, extremely  stable. Handled large power boat wakes with ease.  Virtually no rocking side to side. I was concerned about this but the motion was dampened very quickly. We only motored, have yet to try motor sailing or sailing. The Catalina Direct motor mount performed great. I disabled one of the 4 springs to get just the righ correct amount of lift. Set like this, it was very well balanced. Lowering and raising the 86 pound motor was a very, very easy operaation. This was important as I have a bad back. It was much easier than raising/lowering the 4 hp on the original compac mount. In or out of the water, you could stop at any point in the lowering/raising and the motor would sit right there....even when motoring it was stable at any point in the throw

I sure we took a hit in sailing performance due to the added weight (particularly light air). Will test that next time out.

All-in-all we could not be happier. Performance under power (stability, control, helm control, ride comfort, boat movement, etc) was really nice. Exceeding our expectations on all counts. Motor was quiet and smooth. Only had a  hull vibraation at one very specific throttle setting. Tap  the throttle up or down a bit and it went away.. Several times we were just cruising along at 5 mph, conversing in normal tones and completely forgot we were motoring. One of would note: "oh yeah, we are motoring, I forgot!"

Olay, I will stop gushing.

Be glad to answer any questions. I will report back on motor sailing and sailing trails. As I mentioned, I fully expect to take a hit in sailing performance. 

Certainly not a mod for everybody. However, depending on your boating needs, the Suncat can make a fine displacement  power cruiser.

I should not be too surprised as the Com-Pac Launch is similar albeit electric power.

[Potcake boy]

The centerboard being down will also help dampen the rolling from wakes or beam seas. Some of the worst rolling occurs when you are overtaken by a powerboat. I found that turning your vessel exactly parallel to the boat wake, your boat tends to go up and down rather than to wallow wildly.

You sound very happy with your boat, can't beat that, so who care about a quarter knot when sailing?

Enjoy

[cruz-in]

Thanks for the reply Ron,

That is one of the things that surprised me. During typical Suncat wallowing situations, the boat behaved very well with almost no detectable wobble.

I'l have to draw a vector diagraom or two to figure why addition of weight, where I put it, would reduce/eliminate the wallowing...

[cruz-in]

Okay, was out today with a few upgrades.

1) changed from a 8.5 x 6.5 prop to and 8.5 to 7.5 prop. I found the Yamaha 2 cylinder was pretty torquey at the lower rpms. So i went to a higher pitch prop.

2) added a power thruster. Here is the link.

http://www.powerthruster.com/

Between the two, I was able to reach hull speed with about 500 less RPMs. This lowered engine noise and vibration at hull speed a bit more. I now think I am about at the limit of what I can do to achieve quiet, smooth , long-term motoring. We are very happy with the results.

As far as handling. Today we purposely tried to take on large wakes at different angles. On all angles, the SunCat "Trawler version" handled the wakes with grace. Remarkedly little rolloing in wakes coming from the sides. The added weight of the motor/gas tank and water ballast really seem to steady the hull. 

Next outing we will try motorsailing.

[Potcake boy]

Cruzin,

Nice to hear that you are getting the results hoped for. Thank you for sharing the details, as I'm sure others will benefit from your "rubber meets the road" testing. The SunCat really is a fun little boat to go out cruising on, it just kind of says "welcome aboard", it makes a very nice platform to share the experience with others.