Boat hopping.

[Rivernut]

14ft.jon, 25 Yamaha. Planes out right now, but when wide open it starts hopping, like wave jumping. Water can be dead calm, still hops. Gets sslowly worse, eventually have to ease back on throttle to get it to settle down. Is this a weight issue? Gas tank and battery both in back. Really no weight up front. Just got this spring, still getting use to it. Thanks for any help.

[JimBuck]

Throw some weight in the front until it rides right. The thing with Jon's is there is more surface area on the front hull hitting the water which might lead to porposing like you have mentioned. Good luck.

[fishingguy]

I ditto that. Mud motor guys have issues with that alot. Weight balance is very important on jon boat for sure.

[Rivernut]

Thanks for the replies, already moved battery up front.

[BobT]

I suspect that you already have your motor trimmed down as far as you can. Perhaps you could somehow block the motor to tilt it further down. When I mounted the 40hp on my Lund Rebel I had trouble. I loosened the bolts and added washers under the top ones to tilt the motor head back more. A little trial and error until I found the number needed.

[Rivernut]

Its not trimed down all the way, but it planes out immediately. That tells me its trimmed correctly. It just hops at full throttle, eventually.

[motley man]

Could be shaft is to long and pushing back up and down , or to big a motor for boat. I had this type of problem and it was because to much motor for the boat. I would try what others said and move weight up front and see what happens. Be careful as it can get hard to control if you get to much weight up front and rear lifts up under full throttle. You may have to downsize motor.

[MuleShack]

Would a foil on the motor eliminate the bouncing?

[Rivernut]

It would help to plane the boat out, but that isnt a problem.

[Wish-I-Were-Fishn]

Its not trimed down all the way, but it planes out immediately. That tells me its trimmed correctly. It just hops at full throttle, eventually.

The hop means your trim is not low enough. Try lowering it some and see how it behaves.

[broken_line]

at what speed does it hop??

[river-rat4]

After checking the weight/load of the boat. I would make sure the motor is Centered. I have witnessed it a few times. Take out the tape measure.

river-rat4

[Walleye Guy]

I would bet that the shaft of the motor is too long for the the transom of the boat. Check to see where the cavitation plate on the motor is in relation to the bottom of the boat. If its much below the bottom of the boat the motor has too long of a shaft.

[Fishing Junky]

Originally Posted By: Rivernut

Its not trimed down all the way, but it planes out immediately. That tells me its trimmed correctly. It just hops at full throttle, eventually.

The hop means your trim is not low enough. Try lowering it some and see how it behaves.

This would be my first move.

[Rivernut]

20" transom= longshaft motor. Its a 1442 Alumacraft, rated for a 30 hp. Run a 25hp. I"ll try trimming it down. I do have 2 more settings to drop. A guy on the river yesterday said it was because it was trimmed down too far. Almost forcing the front down , causing the hopping. I will post how it turns out. Thanks for all the input, greatly appreciated.

[Gordie]

If after you have trim your last two settings and it still does this then add weight to the front of the boat like useing your gas tank or battery to equal the load.

[Fredd]

trim it down and that should help, I think they call it porpoising (sp?).

[Fishing Junky]

A guy on the river yesterday said it was because it was trimmed down too far. Almost forcing the front down , causing the hopping.

Your trimmed too high for how the weight in your boat is distributed. Trimming the motor down, should actually get you on plane faster and help keep your bow down and reduce the chance of porpusing. Your boat is light and you might need to readjust some weight forward to totally eliminate the porpusing. You MAY or May not loose top end, but it will be a safer and more enjoyable ride. Good luck. Junky..........

[Rivernut]

Took the jon out today, trimmed it down one notch. That was all it took, you were right. It planed out immediately and didnt porpoise. Looks odd, but works. Didnt notice loosing any top end. If it did, it is minimal. Again, thanks for the help. Mike

[Wish-I-Were-Fishn]

Took the jon out today, trimmed it down one notch. That was all it took, you were right. It planed out immediately and didnt porpoise. Looks odd, but works. Didnt notice loosing any top end. If it did, it is minimal. Again, thanks for the help. Mike

I love hearing that

Glad I could help

[Sandmannd]

Mine will hop a little had full speed, I just trim the motor down a little and it stops hoppin'.