lean to port and Chinewalking on a Humber Ocean Pro 6.3 - Page 2

HUMBER P4VWL · 01 April 2013, 07:22

LOL

I struggle to be LIGHTLY loaded even with no kit on!

all those beer stops take it's toll!

Ian M · 01 April 2013, 08:20

No chinewalking, but I had the issue of the port side of Jianna being lower at speed, despite the engine being offset to starboard by 1.5 inches (38mm). I had two heavy batteries on the port side, the idea being to counter balance me, as I often go out alone, sat on the starboard side. Moved the batteries to the starboard side, and whilst I go down the Lymington river (slowly) with the starboad side down a little, at speed Jianna runs level, even with more crew on board. One happy RIB owner.

Ferdi · 01 April 2013, 10:39

Quote:

Originally Posted by HUMBER P4VWL

Our 6.3 op leans to port when trimmed in, as we trim out it balances up to neutral. Ours too sits v low at the rear, it's just the design. Freeboard on transom is excellent though. Tubes drag slightly in water but gives great stability.

Where are your tanks? We have 140L in console. That should stop chine walking. Ours only just chine walked at 52mph... It's v rare though, we need to be v lightly loaded with no kit on.

The 200 must fly.

mine also has 2x70 liter under console.

52 mph / 83 km/h / 45 kn - this is exactly the speed where it begins with chinewalking.

unfortunatyl this is not the end of speed with the 200HO, but there are still 10 - 15 km/h left which cannot be driven because of the extreme chinewalking.
A little chinewalking I am used to handle, but at about 87-88 km/h it gets so bad that I have to reduce gas.

HUMBER P4VWL · 01 April 2013, 21:41

Quote:

Originally Posted by Ferdi

mine also has 2x70 liter under console.

52 mph / 83 km/h / 45 kn - this is exactly the speed where it begins with chinewalking.

unfortunatyl this is not the end of speed with the 200HO, but there are still 10 - 15 km/h left which cannot be driven because of the extreme chinewalking.
A little chinewalking I am used to handle, but at about 87-88 km/h it gets so bad that I have to reduce gas.

Awesome. Not being funny but if you want a 6.3m hull that goes over 52mph, the Humber OP isn't really the horse for the course!! It's a great deep V for the rough with chines and a high sheer bow to keep you dry. Just enjoy it to 52 knowing it will get you there fast and get there 4-6 up. Ours is a little slow once fully loaded, but love it none the less.

Sounds a nice boat.

Chris · 02 April 2013, 07:28

Blimey a 200HO I missed that. Way too much engine for a 6.3 humber. If you had a 175 etec small block you would still get 45 knots and you would have a lot less weight on the back.

Your fuel bill would be lower too !

Ferdi · 02 April 2013, 07:30

Quote:

Originally Posted by HUMBER P4VWL

Awesome. Not being funny but if you want a 6.3m hull that goes over 52mph, the Humber OP isn't really the horse for the course!! It's a great deep V for the rough with chines and a high sheer bow to keep you dry. Just enjoy it to 52 knowing it will get you there fast and get there 4-6 up. Ours is a little slow once fully loaded, but love it none the less.

Sounds a nice boat.

thanks,

I already love my Humber, its incredible.
But of course I try to solve the issues as far as possible.

9D280 · 02 April 2013, 08:51

For what it's worth mine is the "litrle brother grandad" of yours - a 1984 Hull, 1m shorter, and built to take a 2 cyl (light) 60 of the day.

I also got the lean - but to Stbd. (much worse with my old Yam 55 than the "new" merc clamshell except mine kicked in at about 18 knots! The clamshell is approx 10Kg lighter thwan the Yam was, and due to space constraints my 13Kg Aux is also on the Stbd. No matter how I re-distributed weight I couldn't stop it. The Clamshell (much slimmer leg, also much lighter & with PT can be adjusted on the move it now still leansd slightly to stbd but just moving my weight to my left foot is enough to correct it.

Both engines fitted dead centre.

What I did find was that when I turned the hull over to remove 20 years of antifoul, the last 0.5m has a slight concave which I assume is there as a "built in trim tab"to help lift the stern out. I guess yours will have something similar?

But yeah, chine walking at 45 knots doesn't surprise me!

dp24 · 04 April 2013, 14:23

Our dive club had this problem with out Humber OceanPro 6.3m with Suzuki DF140 (although we're propped for 10 divers not speed! max WOT empty is 34kn).

The RIB would lean to port even with 6 divers on board!

Engine is offset 2-5cm ish to Stbd.

I found that raising the engine height on the transom helped, the boat now only leans when trimmed down fully (engine trying to lift stbd transom).

Anti-vent plate is now ~1cm above keel, feel we can probably lift it more too.

My theory:
Too much engine leg in the water was causing lift on the stbd side (acting similar to trim tab).

captnjack · 04 April 2013, 15:31

Quote:

Originally Posted by 9D280

What I did find was that when I turned the hull over to remove 20 years of antifoul, the last 0.5m has a slight concave which I assume is there as a "built in trim tab"to help lift the stern out. I guess yours will have something similar?

Man you are lucky it doesn't porpoise like crazy with this kind of cup in the hull!

I'm no help on the chime walking but the OP's boat sounds like an overpowered deep-V and trying to do 50knts. That's just not sounding like a good idea.

Ferdi · 04 April 2013, 17:07

Quote:

Originally Posted by captnjack

Man you are lucky it doesn't porpoise like crazy with this kind of cup in the hull!

I'm no help on the chime walking but the OP's boat sounds like an overpowered deep-V and trying to do 50knts. That's just not sounding like a good idea.

50 knots would be fine, 100 km/h much better ;-).
no, its no problem for me, even occasions to drive WOT with it are quite often, temptation to do it is always there, even I get tears in the eyes looking at the fuel usage at WOT :-).

Unfortunatly water on danube is quite calm most of the time, so temptation for WOT is quite often. at vacation in Croaotia it will be different, here the deep V can show its advantages.

but I see, WOT is dangerous.

captnjack · 04 April 2013, 17:32

extreme chine walking is, so good luck with that

Ferdi · 06 June 2013, 10:13

So, after some trials and drives it seems, that in large part my problems are solved.

Lean to port I could solve by simply redistribute the heavier things from left to right stowage under jockeyseats or by biotrim, the extrem chinewalk is completly gone as soon as weight is in boat. With 3-4 persons chinewalking is completly gone and speed is still 86-88 km/h.

Motor height seems ok, because with a heavy person on jumpseat motortrim has to be reduced else propslipping occurs much sooner.

cjj216 · 07 June 2013, 07:00

Ferdi
I also have an OP 6.3 with a df140 on. When I first got it I also noticed lean and a pull to port.

After alot of tinkering with trim I realised that this set up was much more sensitive to trim levels than any of my other boats.
Millimetres can be the difference between heavy steering with a pull to port and a perfectly balanced boat that's easy to flick about.
38 knots 4 up with full tanks (2x70ltr up front) is fine for what we do. Flat calm or rough seems to make no difference to this boat! I've done the fast boat thing and this feels safe and fast enough these days, especially with kids and wife on board.
A 175 would be nice but I agree with some of the other posters, 200 is alot on that hull. On the flat maybe ok but I wouldn't want to rag it wide open on the rough stuff.
Your boat will come in to its own out at sea...just go easy on the throttle!

xpertski · 04 August 2018, 07:56

Interesting reading this thread as I also have an Ocean Pro 6.3 with a DF140, 2004 combo.

At some point in the next few years I would like to replace the engine with one with a bit more power (when it needs replacing otherwise fine for now, great engine!). It has lost a little speed over the years, used to be able to “just” get 39 knots one / two up, but now it’s more like 34 knots. Couple of scrapes on hull and remnants of a keelguard which I need to remove will not have helped but also engine may have lost some horses over the years. I used to find 39knots plenty of speed, though maybe on a flat day a few more knots would be nice.

The issue is when there is a full boat and you lose allot of speed. Which gets me thinking. 175 or 200 HP would be nice. The hull is rated to 200hp and engine technology means the new 200hps are coming in similar weight to 2004 140/150hp engines which can only help with boat weight balance (main reason I went for the 140hp at the time, 200hps back then were simply too heavy).

From my thoughts, if the power from a larger engine resulted in chinewalking beyond 45knts the solution, once everything is tried that can be improved, is to keep the speed below that speed, easily done with throttle control. But having the extra power if you need it has the benefit that when you have 4-6 people on board (or 8 as I will on a trip planned to Isle of Wight in September) your speed doesn’t drop to 30knots max or even less, but can be maintained at 39-40knots (when sea is flat of course). That to me sounds like an ideal nice option to have!

The new Evinrude E-etc’s and Mercury range seem nice! Enough to go from trusty Suzuki??

Jonny

HUMBER P4VWL · 04 August 2018, 13:22

Interesting - we have had a Merc 175hp optimax from new for 9yrs and it really does fly. 53mph with 140L (2x70 plastic in console) 2 up. If I go 1 up and 50L it got to 53mph more easily but as I trimmed out it was then VERY twitchy! However the mid range punch in rough weather is brilliant. 4 up, full tanks and some bags, or 6 up and it goes mid 40s. The V6 growl isn’t loved by the wife and kids though.

We also have anti foul and some weed at end of season.

We’ve ordered for end of season the new Merc 200hp 4s 3.4L V6 (max Hp for the hull) which is only slightly heavier than the Optimax. Dealer thinks it’ll be quicker, nudging to 60mph.

(Engine for sale late September, short sea trials welcome in N Wales/Anglesey, 1 owner, full authorised Merc dealer history, low hours, no expense ever spared, all receipts. Winterised each year.)

As you currently have to trim right out to get from 50-53mph, to go faster you need more torque and power so as not to trim quite so far out, to avoid chinewalk, I’m guessing high fifties, possibly 60 mph but we’ll see.

Time will tell but I hope it’ll be at least similar or a little faster than the 2.5L V6 Opti.

Interestingly someone else said the 200 4S Verado (1.7L supercharged) wasn’t as quick as his 175hp Opti. Though Verados are v heavy engines.

No replacement for displacement.

Safi · 20 October 2019, 07:53

Interesting thread, i have a avon sr6 with a efi merc 225 and its dooing the same thing as the humber it leans heavy to port from 30- 45kts and when trimmed up it starts to chinewalk baadly.
I moved the engine 30mm to starboard and it helped a litle but att 30- kts with engine down or a little upp trimmed the engine is trying prety hard to stear left so i presume its not very good for the hydraulic steering cylinder?
I plan to put the engine back att center and put some trimtabs on but i also wonder if it would help reduce chinewalk if i shorten the propeller hub? (Laser 2 prop)
I have a center console and have tryed to put weight in front like stainles steel tank 80kg battery under seat 25kg 200l fuel and it slows down the chine but starts to bouns at 35kts so it has to be driven with no trim at all.

GuyC · 20 October 2019, 09:33

My sterndrive has a 'heel tab' under the cavitation plate that you can rotate to offset the propeller torque. It sounds it would be quite useful for an outboard although the offset would give a bit more room on the transom for the aux (if you are in that camp).

Being a Pac 22, it doesn't go fast enough to chine walk but it does lean to the right (anti-clockwise prop) if the tab isn't adjusted.

Safi · 20 October 2019, 09:55

Many outboard allso have the heel tab and i have been testing many different settings on other outboards but the engines does allways have some ”torgue steering” att some speed/trim thats not usualy a problem.
My efi merc dos not have a heel tab an i dont think it needs one either, but when i offset the engine the ”torgue steering” increased so much that im afraid it will damage the hydraulic steering att some point.

lifeboatman3 · 28 October 2021, 20:26

Hi
Just wondering if you solved this problem? I have a 6.3 also with a Honda BF175 and its doing the same. Mine has the single console and all the weight is in the middle. I have a 100ltr tank in the middle of the rib so all weight is centered yet it still sits on her port chine. I've looked the the engine has been fitted off centre 4 inches more to starboard. I have also noticed the boat does 32-34knots flat out does that sound about right. My friend and I are going to look at the cav plate when it's out of the water, currently on versa dock.
Any help on this would be great thanks

Limecc · 28 October 2021, 20:51

Quote:

Originally Posted by lifeboatman3

Hi
Just wondering if you solved this problem? I have a 6.3 also with a Honda BF175 and its doing the same. Mine has the single console and all the weight is in the middle. I have a 100ltr tank in the middle of the rib so all weight is centered yet it still sits on her port chine. I've looked the the engine has been fitted off centre 4 inches more to starboard. I have also noticed the boat does 32-34knots flat out does that sound about right. My friend and I are going to look at the cav plate when it's out of the water, currently on versa dock.
Any help on this would be great thanks

A starboard offset might contribute but I recall a Willard RIB with this issue and it was caused by cupping on the prop which in turn affects the shape of the thrust cone and the amount of torque reaction. It was also suggested to adjust the skeg anode in another thread linked below:
Ribeye leaning to Port when under power

Need details of prop pitch and the rpm at 34kn to calculate if it's right. Seems slow to me. By all means you should optimise engine height (as high as poss) and personally I'd centralize the engine unless the space is needed for an aux. It was probably offset on purpose to counteract the torque roll but I'm not sure if it was moved in the right direction or not. Different prop is probably the cure.