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Another Newb question

Dougncrew

Dougncrew

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I took the boat out for the first time this weekend and realized I had some questions.
It is a tritoon with the Volvo 5.7 IO.
Question 1 - What RPM is a good cruising speed? What is the max I should go?
Question 2 - What should my Trim be at when cruising? What reasons would I change other than shallow water?
Thanks in advance.
 
Welcome, Doug!

1. If your instrumentation provides instant MPG information, the it will be pretty easy to find your sweet spot for cruising. Depending on wind, load, etc. my sweet spot is between about 12 to 17 mph. Generally speaking, you'll want to get on plane and out of the water so you're not pushing through the water, but rather skimming on top of it.

2. When you take off, you'll want the outdrive about as low or trimmed down as possible but once you're on plane you'll want to trim it up almost it the point of ventilation (where the prop starts spinning freely) or porpoising (bow bouncing up and down regardless of waves). That will keep the bow up and out of the water, so once again you are not pushing through the water. Once you have it properly trimmed, there really should be no reason to change except for shallow water, stopping/starting or a shift of weight from people moving forward or back.

Post some pics when you have the chance!
 
1. To me, boats are built for wide open throttle. Go as fast as you can afford or are comfortable with. The engine computer should prevent over rev. #2. What Michiman said.
 
Michiman said:
Welcome, Doug!

1. If your instrumentation provides instant MPG information, the it will be pretty easy to find your sweet spot for cruising. Depending on wind, load, etc. my sweet spot is between about 12 to 17 mph. Generally speaking, you'll want to get on plane and out of the water so you're not pushing through the water, but rather skimming on top of it.

2. When you take off, you'll want the outdrive about as low or trimmed down as possible but once you're on plane you'll want to trim it up almost it the point of ventilation (where the prop starts spinning freely) or porpoising (bow bouncing up and down regardless of waves). That will keep the bow up and out of the water, so once again you are not pushing through the water. Once you have it properly trimmed, there really should be no reason to change except for shallow water, stopping/starting or a shift of weight from people moving forward or back.

Post some pics when you have the chance!
Click to expand...
20180120_110753.jpg FB_IMG_1516648148258.jpg FB_IMG_1516648148258.jpg FB_IMG_1516648283400.jpg
 
I/O's do look sweet on a pontoon!
 
IMO I would be cruising at around 3k RPM's, its typically where you find the best speed/fuel economy. With the V8 I'd guess it will be in the high 20's mph range at those rpm's
 
Dougncrew said:
I took the boat out for the first time this weekend and realized I had some questions.
It is a tritoon with the Volvo 5.7 IO.
Question 1 - What RPM is a good cruising speed? What is the max I should go?
Question 2 - What should my Trim be at when cruising? What reasons would I change other than shallow water?
Thanks in advance.
Click to expand...

After you've had your boat for awhile and are used to it.........You won't have to look at your gauges for RPM's, cruising speed, max speed, trim, etc. etc. You'll be able to tell by the feel and sound of the engine and the ride. You'll just know......
 
The way I have found the trim that is right for me is while cruising at my selected speed I kept an eye on my GPS watching the mph and slowly nudge the trim up and down until I hit the maximum speed. Now I know that for me it is at about 3/4 up and I don't generally have to play with the trim anymore
 
Link said:
The way I have found the trim that is right for me is while cruising at my selected speed I kept an eye on my GPS watching the mph and slowly nudge the trim up and down until I hit the maximum speed. Now I know that for me it is at about 3/4 up and I don't generally have to play with the trim anymore
Click to expand...
Yup, this will work just as well.
 
Link's method is exactly how I do it too. 3/4 on the gauge is just about perfect.
 
OK mine is %. so are we talking 75% or 25% showing? Oh well I will do like you guys said and get to a cruise speed / Sound with the RPMs then move it around until it feels right. I am going out again this weekend so I will give it a shot. Thanks again.
 
The gauges being referenced are similar to a fuel gauge with trim all the down on empty and all the up full so to speak, so 3/4 trim would be 3/4 of the way up. Depending on how you gauge starts out all the way down would determine your %. As stated trial/error will prevail to be best way to determine your settings, every time I mess with a prop or engine height I start from scratch on trim levels.
 
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