porpoising boat, 79 skeeter w/ 85 hp johnson

[swamp creek]

this is my first boat and i know nothing about it. i took it out last saturday, took me a bit to figure out how to plane it out. i just gave it all it had, it almost stood straight up and finally came down, the front was up high and kinda scary. then i got it to plane out but it was hopping really bad, the trim was closest to the transom as i could get it, i took the doel-fin off and it planed out perfect for a little bit (when the water was like glass) it doesnt like waves, or the wakes the other boats make. i almost bounced the kids out the boat cause i couldnt slow down in time. the river i took it to is like a
yacht club, every 100 yards, here come another boat bigger than mine hauling tail.

it seemed to run better without the fins, is that normal ? i have a 15' skeeter, 85 hp johnson.

how can i add weight to the bow?

 

[greenbush future]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

The fin you removed is a add on item that may be masking other issues with your boat. How do things look under the floor? Foam wet or dry? boat loaded heavy or light? What prop are you running? what is stock for your boat? May just need to slow down on heavy traffic areas, bass boats aren't built for speed in rough conditions. Standing up on end is not good, may need some weight up front. Snap some pictures of your stern area(back and side shots) do you have power trim and tilt? Could just be a learning curve, and knowing what to expect in different conditions, and not exceeding the boats limits.

 

[swamp creek]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson





i know its heavy in the back, thats where every one sits, if they sat in the front they'd be thrown in the back when i hit it
i guess this motor is the stock motor for it, the other 79 skeeters have the same engine, i think it might be good if i could add weight to the front , but got no where to put it

 

[swamp creek]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

yes it has power tilt trim

 

[metriccrescentwrench]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

If the bow went as high as you describe when you took off it sounds like you didn't have the engine trimmed down enough. For starting out you want to have the engine trimmed pretty much all the way down, that keeps the bow down and helps lift the stern. Then as you pick up speed you'll trim the engine up to get the bow out of the water which allows you to run faster. Trim up until you hear the engine change pitch (the prop is starting to churn air at this point), then go back down a bit. If it's porpoising at speed that's an indication that it's trimmed too high, so trim down a little bit to stop that.

Also, you'll learn that you need to trim down a bit going into a turn, and you can trim back up to your normal running position when coming out of a turn.

Oh, is your trim gauge working?

Once you get the feel of the boat you might want to try putting the fin back on and see if you like it better. With some boats they'll help get you up on plane at a lower speed, and therefore are a help when pulling tubes etc.

 

[swamp creek]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

trim gauge? i dont have any gauges on this boat. i did have the motor trimmed down as far as it can go, as close to the transom as it can get. when i trim up it porpoises even more, so i just rode it all the way down the whole time

 

[metriccrescentwrench]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

trim gauge? i dont have any gauges on this boat. i did have the motor trimmed down as far as it can go, as close to the transom as it can get. when i trim up it porpoises even more, so i just rode it all the way down the whole time

Post a photo taken from the side of the engine when it's trimmed all the way down. Something doesn't add up, I wonder if the trim stop pin is too high.

 

[aspeck]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

Aw yes, the joys of a skeeter SS1 with an 85 on the back! What you describe is a little more exaggerated than normal, but not far off. these things are back heavy, especially with the 85 on the back, 2 full cans of fuel back there, and 2 or 3 people sitting in the seats. If you can reconfigure the 2 batteries to the front, it will help a lot. Also, trim tabs are a big plus ... For the size of the boat, stationary ones are fine. With a little tweaking you can get this boat to run great. but it will take a little tweaking. I know, I had one for 20+ years! Gear boat and a lot of fun after getting it just right.

Practice with the power trim and tilt, also. As you get used to it you will learn the little nuances of the trim for the hole shot and straight shot to keep it from porpoising. As already mentioned, be ready to trim down for turns or she will skip and slide like crazy around turns.

 

[swamp creek]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

yeah that sounds about right aspeck.. there is no stop pin in the motor mount, the motor goes all the way down till it hits the mount itself. i just gotta figure out how to add weight to the front, and i thought about trim tabs

 

[swamp creek]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

i've got a deal on a jack plate for 50 bucks, should i add it and will it help me out from porpoising ? what does it do for me ? i know nothing

 

[chimmike]

Re: porpoising boat, 79 skeeter w/ 85 hp johnson

Another thing, try to be smoother on the throttle. have people sit up front to balance the weight out better and it will get up on plane easier/better. If you're afraid of them getting knocked back when you roll on the throttle, try to do so more slowly. Yeah, that's definitely not a boat for rough water. Make sure everyone's okay with getting wet!