18ft bowrider - merc 3.0lx with alpha 1 - prop advice

[bowler]

Hi all,

My current prop is a 14" diameter x 20 pitch RH Mercury Alpha 4. It was on the boat when i bought it. I think it may be causing torque steering issues and was wondering what others with a similar setup are running as thier prop?

We do a lot of watersports so hole shot is important but the prop steer is wicked, even with trim tab adjusted.

Thanks in advance.

D.

 

[steelespike]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

I don't have any first hand experience but wonder what the max wot rpm and speed is lightly loaded?

 

[Bamaman1]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

Best way to come up with the best prop is usually to find the pitch that'll get you to the redline--4400-4600 rpm's. It might be a 21 pitch in your situation. If you're going to be pulling skiers, drop back to a 19 pitch.

That motor is not a powerhouse coming out of the hole, but will cruise fast perfectly well. Fuel mileage is just great. If you're pulling skiers every time you go out, trade it for something with more horsepower.

As far as torque steer, try another prop--and adjust the tab on the anti-cavitation plate toward the direction it's hard to turn in. That's about all you can do.

 

[smokeonthewater]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

a buddy of mine has almost the same boat, a searay with the 3.0 and a wake tower... It had a 4 blade 21 pitch on it when he bought it and I dropped him to a 3 blade 19 pitch.... It is a whole new boat... planes nearly instantly with two tubes behind it and tops out (not towing) at 40+ mph right at the top of the recommended rpm range.

what is your current wot rpm? also which side do you have your trim tab adjusted to?

Last, look into a no feedback helm.... It still takes effort to turn the wheel but it will stay put instead of you having to fight to hold it.

 

[marcoalza]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

I agree with smokeonthewater.
I have 2 props, 21 and a 19 and the 19 is great for getting the boat up quickly and the wakeboarder.

Makes a massive difference.

SOTW, what's a 'no feedback helm' ??

 

[Tail_Gunner]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

Hi all,

My current prop is a 14" diameter x 20 pitch RH Mercury Alpha 4. It was on the boat when i bought it. I think it may be causing torque steering issues and was wondering what others with a similar setup are running as thier prop?

We do a lot of watersports so hole shot is important but the prop steer is wicked, even with trim tab adjusted.

Thanks in advance.

D.

I doubt the prop is creating tourqe steer. I assume you dont have power steering which will make what you are feeling as a heavy drag....There is a trim anode that you turn....its on the back of you cav plate you turn it in the direction of the pull. Aside from that your prop seems a bit large. You should post your rpm at wide open throttle and speed..4600 rpm is a good place to be with that 4cyl

 

[himmelrr]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

I used to own a 17.5' Caravelle bowrider with the 3.0. I had a Vengeance 21P and it was OK for skiing or tubing. It was the perfect prop for that boat for cruising. I'll bet a 19p would be great for you.

 

[smokeonthewater]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

a no feedback helm lets the wheel steer the engine but the engine can't turn the wheel so wherever you turn the wheel to it will stay there till you turn it again.

The helm is the portion of the steering system that fits under the dash.

 

[bowler]

Re: 18ft bowrider - merc 3.0lx with alpha 1 - prop advice

great advice all,

can anyone recommend a particular prop with 19 pitch - a assume 4 blade would be the way to go? Also, can just the helm be replaced with a NFB helm or should i get the whole kit like the one below:

http://www.nautequipe.co.uk/teleflex-no-feedback-steering-kits-711-p.asp

P.S WOT is currently 4600 according to my tach (which is a bit funny). With a smaller pitch i'd need to keep an eye on those revs but I like the idea of improved hole shot.

D.