Changed Drive Shaft ????????

[scottyboy]

Originally Posted by Peterjfinch

Thanks again, I'll PM him now. If you speak with him, please let him know.

Cheers

Peter

Will do buddy!

[JamesM]

Don't cut the transom untill you've tried everything else. Also if you add 6 inches of setback the motor will be lower anyway. The transom is at an angle so as it back it goes down. 6" back will lower motor and thus the propshaft with respect to the bottom of the boat by over 1" I reckon.

[sinkunit0]

my transom is 24" with the tape flat against it

[Peterjfinch]

Hi Sink,

Mine is 26", measured the same. What's 2" between friends.

See, all this is driving me further into stupidity.

Peter

[RossM]

Hi mate,
Got your P.M
I think:
1: you need to trim in!! big time lol, all the water your kicking up into the air is speed your loosing.
2: you need more bowlift, try using different props, you could also try shifting weight back or adding setback
3:i think youve lost speed because you properly knocked off around 15 kgs taking 5 inches off the engine, meaning your C.O.G is further forward, giving you less bowlift, meaning you need more positive trim to get the bow up so you have less surface area and less drag. as youve had to trim out more you have lost some of the forward motion from the prop and changed it to upward motion, hents the rooster and lower speed.
try shifting weight back, where is your petrol tank? can you get hold of any other props?
try a chopper, there bowlifting.

p.s your hitting the limiter because your letting the engine spin up and loosing all your power through the rooster

[Peterjfinch]

Hi Puppie,

Thanks for your input.

1: I was trying to trim out to get some speed up. Tried different trim untill the last run, when the alarm went off.
2: Bowlift, how? there's nothing to move back. Tank is 200 ltr, under floor, from near the transom to under the dash. Props are hard to buy here, let alone try out.
3: Would adding weight to the stern help?

When you say that Im "hitting the limiter", can you tell this somehow, am I missing it?

Thanks again

Peter

[RossM]

yep i understand that you had to trim the engine out to get the bow up, but doing so you lost forward motion from the prop, made a big rooster, made ur engine rev up more, and lowered your max speed.
yes you need to put weight back, this is what will give you the bowlift you need.
is there any way you could get hold of a couple of spacers for the engine? or next time you go out, bring along an extra person and make him lean as far back as possible,
remember, you dont want to be kicking up a rooster!
your limiter is either 5600 or 5750 which i think is why your alarm went off, because you hit it.

[JamesM]

I wouldn't have thought a 25" mid is 15kg heavier than a 20 a bit maybe but not 15Kg.

[Peterjfinch]

Hi Puppy,

Putting weight in the back has been said by a guy I've been talking to, about this. What sort of weight are we talking about. Would a 30ltr plastic tank, straped into the engine well help?

Peter

[Peterjfinch]

Hi Johnny,

I've been told that setback will take away the sea keeping ability. Any Ideas.

Peter

[RossM]

Originally Posted by Peterjfinch

Hi Puppy,

Putting weight in the back has been said by a guy I've been talking to, about this. What sort of weight are we talking about. Would a 30ltr plastic tank, straped into the engine well help?

Peter

In answer to your question, yes it would help...But phantoms have very thin engine wells!
maybe put a few sand bags that you can put behind the back seat, that way the weight is lower down aswell.

[RossM]

Originally Posted by Peterjfinch

Hi Johnny,

I've been told that setback will take away the sea keeping ability. Any Ideas.

Peter

Adding setback increases bowlift, too much bowlift in the rough stuff can be dangerous, we have 4.75" setback and it runs perfect and handles the chop nicely,
if you have the money IMO its well worth getting a Jackplate.

[JamesM]

Originally Posted by Peterjfinch

Hi Johnny,

I've been told that setback will take away the sea keeping ability. Any Ideas.

Peter

Its all about balance. Move the engine (weight) back and you change the balance of the boat. This may mean that when in flight the boat may no longer stay level but instead goes nose high. This makes driving in rough conditions more difficult and hence slower, you can't see where your going for one . It depends on the boat though as boats with heavy bow's may need set back in order to get the desired balance. Generally Phantoms perform better in the rough with no setback. But as yours has a long fuel tank and you've increased the weight of your foredeck, set back may improve the balance of your boat and thus improve the rough water performace. You won't know untill you try it.

I think they turn better without setback too but to be honest mine (P20) has 5.5" of setback and I've never tried it without. Hope to this year though.

[Peterjfinch]

Hi All,

If I went for a chopper prop, for the bow lift. Any ideas what pitch and does over or through hub make any difference.

Peter

[Burty]

all choppers are the same, over hub i believe. I'd try a 24" if you can.
Offer of a trial of a 22" ET still stands if you can wait till end of may

[Peterjfinch]

Hi Burty,

Thanks mate, it just show how little I know. I'll try to find what I can but yes, when you're over, it wouldn't hurt to try it.

Thanks

Peter

[gar163y]

Try this : http://cgi.ebay.com/ebaymotors/Prope...QQcmdZViewItem

[gar163y]

Or if they won't post to Europe then therhttp://cgi.ebay.com/ebaymotors/Mercury-Outboard-Racing-Propeller-Prop-Modified-Chopper_W0QQitemZ270095579594QQcategoryZ26456QQssP ageNameZWDVWQQrdZ1QQcmdZViewIteme's this one:

[gar163y]

Or if they won't post to Europe then there's this one: http://cgi.ebay.com/ebaymotors/Mercu...Z1QQcmdZViewIt

[Peterjfinch]

Hi All,

Thanks for your help. Can you confirm the following, as I don't have a clue about this. I have been told that the chopper is a stern lift prop, is it?

"Over the hub props create slip, massive slip in the low RPM range 4500 and lower.

You do not have a HIGH RPM engine.
The over the hub prop will not make use of the torque your engine has.

Only making use of 1500-2000 rpm

A lot will argue and some will agree.

If all you want is top end, and not caring weight give one a try.

But it's not for your ride! IMO

Now, their is no constant rule with props.
Sometimes someones dump truck wheel is magic on yours.

But what you have is not! You need lift!
And maybe a Chopper Style prop will work well, it dam sure has lift!

And you need lift!

Find one, try it."
Peter