motor height question

[ken_23434]

I just bought a Suntracker Party Barge 20 this week. I have had it on the water twice. When I get to about half throttle, water starts to splash in front of the motor. Once I get to about 75% throttle, the whole front of the motor cover is wet and water is splashing into the rear of the pontoon.

From what I have read on here and elsewhere, I am pretty certain the motor is mounted too low.

Is this common when purchasing a new boat? I would think the manufacturer would know the correct mount height.

To me, it seems the engine might need to be raised close to 3 inches.

Could anyone back up my opinion on that? I have been trying to get in touch w/ my dealer, but they have not returned any of my messages.

 

[vergil]

Re: motor height question

i had the same problem on my pontoon but i run a 75 hp johnson, what i had to do was move the pin to keep the motor from trying to lift the boat but rather push it, (it plained a lot better) by the looks of your pics you have the same pin just set up just a little differnt, mine moves out when yours apears to move up, now you have tilt and trim correct? the pic that show the pin the best is #5 they way the pics look is that the position the motor is in when full throttle if so the prop angle looks off, not so much as motor height
i hope this helps

 

[EGlideRider]

Re: motor height question

Good question... I would try raising the motor a couple of holes and see what happens.

 

[ken_23434]

Re: motor height question

Are you talking about the smaller bolt that goes from port to stbd?

If I understand what you are saying, I should move the bolt so that the motor does not trim "down" as far, correct?

When trim'd all the way down, the prop has moved past horizontal and is pointing "up" at the bottom of the boat (if you draw a line from the back of the prop, though it's centerline, that line points up to the bottom of the boat).

 

[EGlideRider]

Re: motor height question

No. But you might try that first.

If that doesn't work, then actually raise the motor a couple of holes. Do so by removing the cover and using a come-along to raise the motor.

 

[vergil]

Re: motor height question

Are you talking about the smaller bolt that goes from port to stbd?
the bolt right behind the dog leg, it has pre drilled holes all around it for differnt postions on the side. when the motor is all the way down it should be resting on that bolt, on a johnson motor that bolt would be a pin i believe

If I understand what you are saying, I should move the bolt so that the motor does not trim "down" as far, correct?
Correct, if your not carefull you can put the motor in a postion where it tries to lift the front of the boat when trimmed all the way down


When trim'd all the way down, the prop has moved past horizontal and is pointing "up" at the bottom of the boat (if you draw a line from the back of the prop, though it's centerline, that line points up to the bottom of the boat).

here is where you lose me what do you mean the prop moves past horizontal, is the motor trimmed all the way down in the pic?

 

[ken_23434]

Re: motor height question

In the pictures, the motor is trimmed all the way down. To me it seems like it goes all the way "down" but goes to far. I would think it would stop at "6 o'clock" if it was a clock dial. When I trim it all the way down, it continues until about 6:30.

Hope that analogy made sense.

 

[vergil]

Re: motor height question

that makes perfect sense. thank you , now that said my 75 johson pushes are 24ft pontoon best at about 5:30, when you move that bolt it should keep it at 6:00, then if you move it agian then roughly 5:50, then 5:45 etc.. you will want do do this on the lake so find shallow water and be very careful so you dont drop anything, move it a little bit at a time then try it out trial and error till you get the results you want. another thing pay atten. to the sound of your motor rpms. as i moved the pin on our johnson you can hear it turning a little more rpms, boat goes faster and it doesnt use as much fuel
i hoped this helped some,

 

[crb478]

Re: motor height question

You have very turbulent water coming off at the motor that is why the motor is set so deep. I would try to raise the motor one hole to see if it runs better. If it does then maybe try two. How many people normally ride in your boat? Lots of times everyone wants to ride in the front which is another reason motors are set low. You can move more weight to the front of the boat which will have the effect of raising the propeller higher in the water. See if it runs better that way. It is really trial and error to get the best set up for the way you use the boat.

 

[ken_23434]

Re: motor height question

I just raised the motor by 2 holes. I also moved the pins that limit how far it trims down by one location.

I will be dropping it in the water this afternoon to check. Sure glad the motor had that lifting padeye built into it.

 

[EGlideRider]

Re: motor height question

Please report back your findings.

 

[ken_23434]

Re: motor height question

I will.

Didn't get a chance to get to the water today. Plan to try again tomorrow.

 

[Jeep Man]

Re: motor height question

Ken, I have the same boat and motor, except mine is the regency edition. I have mine set at the center hole. No problems.

 

[ken_23434]

Re: motor height question

OK, made it out today. We had 11 people on board this time. My wife always likes to max out everything (# of people on the boat, supersize the value meal, credit cards, ...). 4 were adults and 7 small kids.

Ran it less than 1/2 throttle most of the day, but did take it to full a couple times. No water splashing from the front of the engine what so ever. So, I am happy now w/ that.

My next issue is that I would hit 6,000 rpm and the throttle wasn't full open, even loaded as much as I was. So, I guess I need to look into getting a bigger prop.

Once again, I am shocked that the boat straight from the manufacturer was not dialed in better. I expected w/ the boat loaded down like it was, that it would struggle to get to 5,500 rpm.

Still happy w/ the boat, though. It was a good day out on the water.

Below is a cell phone pic of it now. Before, the cowl would look practically swamped and my camera probably would be getting splashed.

 

[EGlideRider]

Re: motor height question

Glad you solved that problem. Did you have the high RPM's before? If yes, then you do need a higher pitched prop. If no, check carefully for ventilation in case you have raised the motor too much.

 

[ken_23434]

Re: motor height question

It had the engine RPM problem before, but that was w/ me and a couple kids on. I thought that since the boat was so lightly loaded that might have been why I was experiencing the high rpm.

I don't think it will be loaded any more than it was yesterday (full tank of gas too).

I am just not sure what prop to get. The prop tools all want an engine speed w/ loading etc... but I think it assumes the throttle is full open. The Michigan Wheel site recommended a 9" pitch, 4 bladed prop when I told it my engine speed was 6K. If I lied, and said 6,300 rpm it recommended a 10" pitch prop. I threw that 6,300 rpm in there just cause I figured if I opened the throttle all the way, I might see that high.

I was leaning towards the 10" pitch one, cause the boat would normally be loaded lighter than it was yesterday, so the steeper pitch would probably work out better for most of the trips to the water.

 

[Jeep Man]

Re: motor height question

Is your motor a Bigfoot model? With a 14x9 my max RPM is 6200. With a 14x11 I'm around 5600. Rule of thumb is 200 rpm for every increment. I'd experiment with an 11 and a 13.

 

[EGlideRider]

Re: motor height question

As Jeep Man said, you an 11 or 13 and I would lean toward the 13.

If there is a good prop shop near you, they can repitch your current prop. Or a local dealer may ship yours off for you.

Good luck and report back your findings.

 

[Water logged]

Re: motor height question

What is the pitch of the prop currently on the boat? It would be easier to determine what you need if we knew what you started with.

Glenn

 

[ken_23434]

Re: motor height question

What is the pitch of the prop currently on the boat? It would be easier to determine what you need if we knew what you started with.

Glenn

Ooops... thought I mentioned that. The current prop is a 3 bladed Mercury aluminum 8 pitch by 12.25 diameter. My motor is NOT the BigFoot model. Just the regular 4 stroke 60hp EFI.

I took it out again tonight. This time, 4 small kids (each about 50#) and 2 adults. The engine was hitting 6,000 rpm at about 3/4 throttle.

The local prop shop recommended getting the 9 pitch 4 bladed prop (I told him I preferred the 4 blade, he was trying to push towards a "regular" 3 bladed). He said that going from 3 to 4 blades w/ the same pitch would be similar to stepping up to the next pitch and staying w/ a 3 blade prop. So, the 9 pitch 4 blade would be taking "2 steps up" from the 8 pitch 3 blade I have now.

I expected that a 4 bladed prop would produce a lot more thrust than the same pitch 3 blade... something like 33% more... I guess the math doesn't work that way.