Scorpion 8.5m Suzuki DF300 4blade

1978SeaRider · 09 July 2019, 12:24

Hi,

Any advice would be great

Looking for a 4 blade option to try and reduce the boats tendency to lean left and cavitate on heavy acceleration... I’ve got lenco tabs

Has anyone tried a 4 blade pls and if so which pitch do they suggest, looking for hole shot rather than top end, or just a nice allrounder

Thanks !

Pikey Dave · 10 July 2019, 08:38

Quote:

Originally Posted by 1978SeaRider

Hi,

Any advice would be great

Looking for a 4 blade option to try and reduce the boats tendency to lean left and cavitate on heavy acceleration... I’ve got lenco tabs

Has anyone tried a 4 blade pls and if so which pitch do they suggest, looking for hole shot rather than top end, or just a nice allrounder

Thanks !

My go to 4 blade prop is the Mercury Rev4, no idea what pitch you need without knowing figures/numbers/current setup. Even with those it would be an educated guess.
Which prop are you currently running & what is your WOT? Have you tried all the usual options for curing lean etc. Raising engine, adjusting trim tab etc??

1978SeaRider · 11 July 2019, 12:52

Thanks Dave, I’ve currently got a 3x16x23 not sure what the max RPM is, hopefully checking that tomorrow. I’m having to almost fully extend the left tab to keep her level. Trying to avoid moving the engine

Frar · 11 July 2019, 14:39

What PikeyDave said 👍🏻👍🏻👍🏻

Pikey Dave · 11 July 2019, 14:52

Quote:

Originally Posted by 1978SeaRider

Thanks Dave, I’ve currently got a 3x16x23 not sure what the max RPM is, hopefully checking that tomorrow. I’m having to almost fully extend the left tab to keep her level. Trying to avoid moving the engine

You need to get the engine setup correctly before you start chucking money at props. Is it a new install? Has the engine been offset correctly? Has the engine trim tab on the leg been set correctly, is the engine height correct?

1978SeaRider · 12 July 2019, 17:43

Engine’s not changed since it was installed at the factory so hopefully it was done right. Took it out today and max revs I can get is 5250 trimmed right up and flat out... think the max recommended is 5200- 6200, so some spare RPM to use. Engine tab looks fine too

jwalker · 12 July 2019, 20:01

Quote:

Originally Posted by 1978SeaRider

Engine tab looks fine too

In what way does it look fine? You need to set it by trial and error.

Knowing that the single engine will list the boat to the left and not wanting to move the engine you've only got a few options left to improve it.

One of them is the engine trim tab: When you steer the boat left it leans to the left so you need to adjust the trim tab so that the tab forces cause you to steer a little to the right so that the boat then tries to lean to the right. It's a balancing act and you may not be able to completely neutralise the forces but since you've got transom trim tabs I'd expect you can get it within acceptable range.

Put the fat people to the starboard side...

Edit: Just a thought, if your transom tabs are Bennett, the switch is marked with reference to the bow not to the stern so if you press the left switch down you are actually lowering the right tab. Other tab manufacturers may be similar, I've no experience of others.

Pikey Dave · 12 July 2019, 20:45

Quote:

Originally Posted by jwalker

.....
Edit: Just a thought, if your transom tabs are Bennett, the switch is marked with reference to the bow not to the stern so if you press the left switch down you are actually lowering the right tab. Other tab manufacturers may be similar, I've no experience of others.

Lectrotabs are the same as

1978SeaRider · 01 August 2019, 10:35

Hi, I’ve spoken to both Scorpion and Suzuki and they have me measurements to check on transom height position etc and it all seems fine. I’ve had Lenco tabs fitted so no issue with the controls... used the engine trim and tabs more this weekend and it’s riding a lot more level which is good (also moves the weight internally to help).... so now the only issue seems to be revs, she won’t rev to within the many factors guide lines... I’ve spoken to Steel Performace who can do a 4 blade that will increase revs by approx 600rpm, but it’s best part of £600... very tempted but not sure if anyone in here has tried their products and the results ? Thanks !

gtflash · 16 August 2019, 19:36

My scorpion leaned to left. All the weight was centre. Moved battery and oil to right and swapped it from lhd to right to counteract. Plus a few other things.

Also Check for trapped water in cable ducts. A long poking pole and listen for sloshing

gtflash · 21 August 2019, 20:46

Another thought. Have you got a picture of engine height relative to bottom of boat. Engines too low can cause prop torque