Weedless or Hydrofan

[seagull101]

Hi everyone,
Is their a difference in speed or power comparing weedless and hydrofan propellers?
I have also always wondered which one is the most efficient at high speed!?

Just thinking ahead with my model 75 as i want the quickest propeller on it.

Cheers, Jacob

[Charles uk]

Is there a Hydrofan for the 75?

[seagull101]

No but there are plenty hydrofan props that will work on the 75 gearbox, century 100 and 102 ones.

[pat777]

Just posting this list of Seagull Outboard Gearbox Ratios, to show which models have the same ratio in case any newbies are reading this topic. Links to previous discussion of gearbox ratios. viewtopic.php?f=2&t=4776&p=38579

I'm not concerned with going fast as I'm only cruising up and down the canal at 4 mph, so I can not add anything further to the topic in terms of experimenting with different props. Jacob you may find that you have to experiment yourself with the different propellers that suit the model 75.

I've noticed in previous discussions on this site that there can be a fair amount of secrecy when it comes to making Seagulls go faster due to the many races that are held all around the world. After all everybody wants to win the race!

Gear Ratio - Number of turns of the flywheel : Number of turns of the propeller.

UPDATED LIST OF SEAGULL OUTBOARD GEARBOX RATIOS

FORTY MINUS
FORTY FEATHERWEIGHT
MODEL 45 ------------------------------------------------GEAR RATIO - 21 : 10


40 MODEL
FORTY PLUS MODEL ------------------------------------GEAR RATIO – 35 : 10


CENTURY 100
SILVER CENTURY-----------------------------------------GEAR RATIO – 35 : 10


CENTURY PLUS
SILVER CENTURY PLUS
Model 80--------------------------------------------------GEAR RATIO – 48 : 12


QB SERIES
KINGFISHER
OSPREY
SEAGULL 5 & 6 (grey coloured)------------------------GEAR RATIO – 3.1 : 1 (FNR)


SEAGULL 5 & 5R (light blue, Yamaha leg)------------GEAR RATIO - 2.03 : 1 (FNR)


FORTY MODEL WITH CLUTCH
CENTURY 75
CURLEW
MODEL 102-----------------------------------------------GEAR RATIO - 2.5 : 1


MODEL 102 PLUS----------------------------------------GEAR RATIO - 4 : 1


MODEL 90
MODEL 110
SD110 INBOARD
SD160 INBOARD-----------------------------------------GEAR RATIO - 3.1 : 1 (FNR)

[Robin Anderson]

Having tried the semi weedless curved blade props on both my 40 Featherweight and Silver Century Plus in direct comparisons, I have gone back to original Hydrofans. The thrust, particularly at low revs in my experience (on my boats anyway) is definitely better with the original Hydrofan and I think top speed is also slightly better - - although speed is hardly the correct word for the breathtaking velocity these power horses can provide I also have Hydrofans on my 40 + and Century 100 and imagine that they also perform slightly better than the semi weedless props which I have for them.( Not tested them directly.) I don't think the semi weedless props are particularly efficient - but I am sure they could be made more efficient by skilful polishing and no doubt the racing gull owners work wonders with bespoke props.
I think the only reason to go for the stock semi weedless props is that they do shed weed to an extent - the Hydrofan does tend to gather all the weed that is going and does not let it go.

[headdownarseup]

hmm, i've noticed this too.
I quite often use a silver century plus on my 17 footer. I've tried both props on this motor and actually prefer the weedless over the hydrofan purely because it pushes my boat (for whatever reason) much quicker than a hydrofan. No jokes, it's literally twice as fast. Why this would be i have no idea.
Curvy rounded blades seem less prone to picking up weed compared to a squarer tipped blade of the hydrofan props.
To me anyway, round is a better shape.

Jon