Planning Speed

[2455bayliner]

Can anyone help.

How do you know the correct planning angle for your boat? At present I have a 2455 Bayliner 5.0L but need the trim tabs down to get the front down, I have put any weight normally carried in the front. Should I put some ballast in the ancor locker to lower the front????

I run with the leg all the way down, also what speed should I be getting?

Thanx for your help

 

[hlb]

Depends what you want to achieve. It's set right when the boats going fastest. Experiment. Or if going into the waves, you want the nose down. With the sea behind you. You want the nose up. Getting it the wrong way round can be dangerous. Dont add weight to the bows.

<font color=red> No one can force me to come here-----------
----- I'm a Volunteer! /forums/images/icons/smile.gif

Haydn

 

[jointventureII]

we had a similar boat, a fletcher zingaro with 2 x 280 merc's.
OK, we didnt need to adjust the trim to get planning but found that tilting the legs and the tabs to a certain point gave extra knots (on top of the 42 it already did)
for less fuel. Dont bother putting the weight in the front though, it can be sorted with the trim of leg and tabs usually

JVII

 

[spannerman]

I am a boat mechanic for the Bayliner dealer on the west coast of Norway and run a 2655 myself. Is this the original engine as we have never seen a V8 5.O in a 2455, they always have V6's. I have the 5.OL myself and I have never had a problem with getting on the plane and only use the trimflaps if I have 5-6 onboard. Do you have the right prop, what is the max RPM you attain? Should be 4400-4600 0n the 5.O Does the trim work correctly i.e. is the leg trimming right in, have the trim cylinders been changed at some point as there are 3 diffrent types on Mercruiser depending on age and model and maybe they are incorrect.
As regards trimming the boat start with full down and when it is on the plane gradually trim up/out until you see the bow rise in relation to the horizon, the boat should run at a steady 3-4 degree bow up angle, if the bow starts to bob up and down (porpoising) you are too high, a dab of down will cure it. It helps to trim down a little before turning at cruising speed as this stops the boat sliding sideways, as the bow section then has a better bite on the water, ( as boats actually steer from the bow, we just push the stern sideways with the rudder or sterndrive to initiate the turn) then trim out after the turn. its amazing how many people don.t understand the principles involved and just leave the trim fully in or out, I have met both types who drove their 36ft cruisers like that, one all the way from Oslo to Stavanger with the drives fully in and wondered why the steering was so sensitive! Hope this is of some help Steve

 

[Col]

Er, beg to differ, they're not all V6's . A few years ago I had a 2455 sunbridge with a 5.8 ltr V8 OMC.
(Ford based)

<A target="_blank" HREF=http://www.arweb.co.uk/argallery/colspics> Cols Picture Album</A>

 

[duncan]

You temp a whole book on the subject of triming an outdrive/outboard boat with a question worded in this way - and [bold]spannerman[/bold] has outlined the basics outwith trim tabs and weight distribution.
With so many variables to play with it is important to differentiate your objectives. If everything else is fine then Haydens ([bold]hlb[/bold] spot on (as usual) but I sense an underlying diagnostic question so suggest that you do the following in a nice empty flat area..........
trim in, tabs down, accellerate to around 15 knots at which you should be fully planning. Tabs up to neutral (they are only drag at this speed on a fully planning hull) and then trim out the drive bit by bit until you start to lose boat speed. Back in a touch then apply full throttle. Wait for it to stabilise (told you to get a big flat area) then try trimming out a bit more to see if you can get anymore boat speed. If you can fine. Now check engine revs and speed and check revs against manufactures recomended for engine - this will establish whether you have the right prop. Note - if you have an Alpha drive, most likely, you can also check trim by letting go of the steering wheel - carefully! - when the boat/drive is correctly trimmed the steering is neutral. applying trim up / down from here will actually steer the boat left and right!!

Hope this helps - if you are in Poole practical help can be arranged for the measly cost of a bar bill - but I have to bring friends.....