lauching problem

[nightvision]

Hi all,<br />Yesterday, we had a little problem launching and I'm just curious to get your comments. <br /><br />On our 180 bowrider (3L, 135 hp) the capacity is 7 persons with a total of 900 lbs. We had seven people and a total of 875 lbs. We wanted to test the boat performance at it's full capacity. <br /><br />We had six people on board as we launch the boat. The trailer was back in and the bunks were about one inch under water. We release the winch and safety chain and the driver tried to push the boat in but could not get it off the trailer. We then had to back the trailer much more and the truck back bumper was now touching the water. We were then able to push the boat off. <br /><br />Question b:<br />a. I'm assuming that we had too many people and it was weighting down the boat. We should have unloaded some passenger and launch. We were also at a new ramp and not familiar with the steepness of the ramp. Could the shallow nature of the ramp be the problem also? I did notice the the ramp angle was not too steep. This was the first time we had to back the truck in so far.<br /><br />b. The boat actually performed fine with the heavy load and I was impressed. We tried some tubing with the full load and it was fine. Although, it was slower to plane. However, am I straining the engine by putting the max capacity weight and asking it to do some tubing. We only went about 15 mph? Is this harmful to the engine? Or is it a matter of the just taking longer to plane and no strain is placed on the engine?<br /><br />Thanks.

 

[Silvertip]

Re: lauching problem

Since the boat probably draws a foot or more of water when afloat, the fact the bunks were only an inch under water and you had an extra 875 pounds in the boat, it certainly was not capable of floating. Are there no dock facilities at that ramp? Launch with the operator only, pull to the dock, load the people and go. You need to pick up the tow vehicle operator anyway so this appears to be a "process problem" not a ramp or trailer issue. To determine if you are straining the engine, you need to understand what the tach is telling you. If you can't rev to near wide open throttle rpms, yes, you are "lugging" the engine. You should have two props for your boat. One for cruising, and one with lower pitch for your activities that require "power" (but that will reduce top speed and increase RPM so watch the tach).

 

[tommays]

Re: lauching problem

as a 3.0 owner who does pretty much what your talking about<br /><br />you are going to get much better results with a smaller prop<br /><br />in my case when i have a light load i use a 19 in prop<br /><br />if i load up with 6 people and stuff the 19 will work but a 17 in works much better<br /><br />every boat is different but with only 135 hp you will have to make some comprises to get the best fully loaded performance<br /><br /><br />tommays

 

[nightvision]

Re: lauching problem

Thanks for the replay.<br /><br />We will now keep a light passenger load and pick the rest of the family up at the dock. <br /><br />Tommay,<br />You talk about using a 17 prop. When you are loaded up with passengers, do you bring the prop along and change between activities or do you use the 17 prop throughout the day? If I remember correctly, when we had a full load (875lbs) we just kept it under 3000 rpm. Would a 17 prop be advisable in our situation? THanks.

 

[tommays]

Re: lauching problem

i just pick the prop i am going to use that day<br /><br />as far as the size it depends on what your useing now and the WOT you get<br /><br />a lot of 18 ft boats ship with a 21 in prop<br /><br />there is allways a bit of trial and error finding the best prop<br /><br />tommays

 

[CATransplant]

Re: lauching problem

Personally, I consider it unsafe to launch with passengers on board. It's always going to make launching more difficult, and the slope of the ramp makes it dangerous.<br /><br />On my boat, there are no passenges on board at launch time. They board at the courtesy dock. If there's no courtesy dock, I'll beach the boat for passengers to board. <br /><br />Too much weight, too much danger.

 

[rwidman]

Re: lauching problem

Originally posted by CATransplant:<br /> Personally, I consider it unsafe to launch with passengers on board. It's always going to make launching more difficult, and the slope of the ramp makes it dangerous.<br />

Agreed. Only the operator in the boat and only the driver in the tow vehicle.