Boat loping at high speeds

[oldtimer57]

When you say “loping” it sounds like you mean bow is rising and falling? I can think of two things. (1) trim angle is too much, try backing off on the trim a bit; (2) jack plate is too high allowing the prop to slip, then grab, then slip, etc. Again, try lowering the engine height ¼” at a time to see if there is improvement.

Or are you talking about chine walking where the bow wobbles from side to side? Different issue, although similar causes. Problem is not quite clear based on how your query is worded… I’ve re-read it several times. I begin to think you are talking classic chine walking when you mention “bouncing even when low”. If so, that is an issue that first needs driver input. There are several good posts on here detailing how to stop chine walking before it starts. Proper balance of the boat left-to-right, and fore-to-aft, non-excessive trim angle, tight steering with no slop, no broken motor mounts, or loose bolts, no air in steering, the list goes quite long…

[Cajunhunter67]

Oldtimer
Sorry I wasn’t clear in my post.
It isn’t chine. I am familiar with controlling chine.
This is the bow dropping than rising. Like the prop is losing bite. Bow falls than the prop bites and picks the bow back up.
I have tried raising the jack plate up and tried lowering it. I have moved it from 3 inches below pad to 4 inches using about 1/4 inch adjustments each time.
Whether I use a small or large amount of trim, the bow will start bouncing.
With the 4 blade prop and a good chop I was able to get it to stabilize and the chine was easy to drive. The wind died in the evening and the water smoothed out, so the loping started again.
My guess is with a good chop there is less drag on the pad and the prop holds up the bow.
Smooth water has more drag and the bow drops.
I just find it hard to believe that neither prop will hold the bow up on smooth water.
I don’t carry a ton of tackle.
About ten Plano boxes in the forward center locker and 15 poles in the port.
Another 6 Plano boxes in the passenger rear locker.

[Bass Cat Boats]

The question is how much steering torque do you have? If there is torque, then we feel there is an engine height or propeller bite issue. Since the propeller was reworked by Gilbert, the question becomes was there any damage cleaned up? If so, then we don’t know the condition of that propeller. Have you run another 24 Fury in 3 blades?

We understand the feeling that you need to try another propeller, though we would try the same one to eliminate the most inconsistent part. The lope is either propeller or engine height usually. We assume they checked the hull, and there little chance anything is in error, though it would have had to have been requested as they may overlook issues. With a Pantera II style bottom the chances of imperfections are almost bullet proof as we’ve never seen one. The hull is generally very similar to models going way back on the Pad bottom. It has nothing critical like other bottoms we build and would be very unusual to have an issue.

You have not read one post where BCB moderators have spoken well of the Four Blade Fury for most general applications. It is a specialty wheel and we just don’t think it serves all needs.

[kls2020]

I believe most people call what you are describing as “Loping” to be “Porpoising”.
As was previously stated it is usually caused by too much trim /to little speed .
I’d be curious to see if you removed all of the weight from you boat and power poles if the problem goes away?

[Bass Cat Boats]

No, there is a distinct difference in lope and porpoise. Lope happens at higher speeds and is water connection. Porpoise is hull transition at lower speeds.

[Cajunhunter67]

The steering torque is dependent on my engine height and trim, which I have adjusted to many different positions to troubleshoot this issue.

I have not the opportunity to try another 3 blade furry. I have quite a few PII in the area with the 25 Fury 3. I am sure I could borrow one and see if the lope goes away. I believe that’s my next step.

I tried to eliminate every troubleshooting possibility before posting agan minus a different 3 blade prop.
Both props were brand new with little to no time on them.
Don

[Redngoo]

The fury performs well deep. Honestly the way i found the right height. I lowered mine all the way down and started back up. Though i have a atlas which made it easy. My p2 came from your area. It had a fury 25. Which i had worked by gilbert. Seems to be the right prop for mine. I did try a tempest was ok as well

[Cajunhunter67]

Redngoo wrote:

The fury performs well deep. Honestly the way i found the right height. I lowered mine all the way down and started back up. Though i have a atlas which made it easy. My p2 came from your area. It had a fury 25. Which i had worked by gilbert. Seems to be the right prop for mine. I did try a tempest was ok as well

I had the 24 Fury 3 as deep as 4 inches below pad. Still loped. Its frustrating because the worked 24 works perfect. With dual poles, and dual consoles it shoots out the hole and accelerates like a 4 balled cat on a tin roof! It also handled well at low speeds and running the bayou curves. It just wont hold the bow up at upper speeds.

Hopefully I can get one of my buddies 25 Fury 3 and try it. If it remedies the loping, than I know its a prop issue. I really believe that’s the issue. I just need to verify it.
Than I will have to see if anyone wants a worked 24 Fury 3. Lol!

[Cajunhunter67]

kls2020 wrote:

I believe most people call what you are describing as “Loping” to be “Porpoising”.
As was previously stated it is usually caused by too much trim /to little speed .
I’d be curious to see if you removed all of the weight from you boat and power poles if the problem goes  away?

Once thing both props do well is hold the bow up at slow speeds, regardless of trim angle. Since Ronnie worked the Fury 3, it lifts the bow nearly as well as the Fury 4.
Its 64 mph and up that the bow starts bouncing.

[schodackbassman]

I second trying the 25P 3 blade. This hull (PII and old Classic) like the 25P and 26P.

[Shap from La]

Cajun, I had the same thing on my old classic. I winded up changing my motor mounts and steering bushings and it mostly eliminated the issue. Basically, at higher speeds my motor was moving around on its on due to a busted mount and excessive slack in the steering. It might have nothing to do with your issue but it’s worth looking in to.

Chris Coupel
Paulina, La.

[Cajunhunter67]

Shap from La wrote:

Cajun, I had the same thing on my old classic.  I winded up changing my motor mounts and steering bushings and it mostly eliminated the issue.  Basically, at higher speeds my motor was moving around on its on due to a busted mount and excessive slack in the steering. It might have nothing to do with your issue but it’s worth looking in to.

Chris Coupel
Paulina, La.

Chris
Appreciate the input. I went out and checked the motor for movement, and checked for engine movement ( Yes not smart, but looked behind me at 65 mph) while it was loping. Engine looked solid. Boat has less than a 100 hrs on it.
I had back to Nigeria on the 2nd of Dec. I hope to locate a 25 Fury 3 to test before heading to work. I have located another 24 Fury 3. Just got to take it off my buddies boat. Maybe next week.

[Bass Cat Boats]

Yes… same topic and it’s slippage.. not all props are created equal and some don’t stay that way.

[Sheff]

My 05 Puma would do this anytime I was over 78 mph. It was the fastest BC I’ve owned to date at 84.7. Lou (motor toter guy) is a friend and he suggested having a touch of cup added to my prop. Knowing he’s a go fast guy, runs a 20′ Bullet with a worked 300X, I listened. I had it done and it cured my problem.

[schodackbassman]

Had a conversation with John Crews few years back in Worcester MA about Fury. Said it needs to be tuned every hundred hours under conditions he fishes in. Sure that applies to those who run long and hard often too.

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