Thread subject: Whaler Central - Boston Whaler Boat Information and Photos :: Hydrofoil thoughts?

Posted by Will21 on 08/05/21 - 3:23 PM
#1

2005 130 sport 40hp

I have had plane issues with my family onboard my 130. There seems to be a lot of people really happy with installing hydrofoils. Does anyone have any experience or advice on such a modification?

Posted by Phil T on 08/05/21 - 3:44 PM
#2

Typically hydrofoil's are a bandaid to a problem not addressed.

For all models under 15', the engine should be mounted one hole up with a stern lifting stainless prop.

If lower planing speed is needed, a 4 bladed prop is recommended.

Posted by gypsmjim on 08/06/21 - 5:11 PM
#3

I've been using DoelFin hydrofoils on boats since 1984. In total I have about 60 boat years experience. My only caveat is that I have no experience with the other re-engineered designs.

That said, my Whaler Montauk has one and I couldn't live without it.

The other caveat is that indeed the motor must be raised so that the fin planes the water at speed. Otherwise it may provide the desired lift on the hole shot, but it could also impact top speed.

Band-aid, schmandaied. Tune your boat with a prop that delivers WOT at max spec RPM, raise the engine to the optimum height and that's what's needed anyway. With that accomplished, add a fin and enjoy the added benefits.

Braking off the AV plate, collecting trash and weeds, etc. are all urban legends.




Posted by CaptCol on 08/19/21 - 11:26 AM
#4

I put one on my 2013 130 Super Sport. It helps with the pitch issue. I got the one that is no drill mounted. As for top speed, sure it is more drag in the water. But at top speed, you are in almost calm water or you are asking for a wipeout with a wave, this boat literally hops off the backside of waves, plenty of flats boats have had mishaps with similar touchy handling characteristics.

Edited by Joe Kriz on 08/19/21 - 11:56 AM

Posted by butchdavis on 08/20/21 - 7:35 AM
#5

Typically hydrofoils are not as useful as proper propeller selection and engine height adjustment. Something as simple as a good engine tune up and fresh fuel can often improve performance more than one would suspect. On boats as small as 16 feet LOA can also benefit from judicious weight distribution. I say this from experience and don't mean to imply larger boats cannot also benefit from redistributing weight.

Engine mounting height is such an easy chore and costs virtually nothing to accomplish. I continue to be surprised by the number of owners who hesitate to try various height adjustments before taking on more expensive solutions. Propellers, especially steel ones, are expensive devices for experimentation.

Posted by Will21 on 08/27/21 - 6:13 PM
#6

Thanks Butch. Based on your comments, do you have some more advice. I looked at my engine height after you said this and my 40 hp engine is on the lowest possible notch out of 5. Seems like that may be my issue??

Posted by butchdavis on 08/28/21 - 7:05 AM
#7

I would raise the engine one hole up and test the result. If you feel adventurous go up two holes and test.

Get back to us with the result.

Posted by Phil T on 08/28/21 - 8:25 AM
#8

You don't say what kind of load you have in the boat when the issue is present. What does "family" mean in terms of people and weight?

Please detail the typical load (fuel, people, gear etc).

What is the existing prop; make model and size. The part # is typically stamped on the inside of the hub.

Also note the 130 Sport of that era was on the underpowered side.

Posted by Will21 on 08/28/21 - 1:05 PM
#9

Myself 185, wife no clue, kids 6 and 9, 6 gal fuel, maybe a small cooler 25 pounds maybe. I have the black max 14 pitch, 816706A45

Posted by Phil T on 08/28/21 - 1:46 PM
#10

I would shift the cooler to the forward area.

Given the low power rating for this model, you may need to be more aggressive with your acceleration to get on plane. Once there, back off on the throttle to get to your intended cruising speed.

Warn your crew to hang on and then move throttle quickly to full throttle to get up on plane and then reduce throttle to get to cruise speed.

Report back results, questions etc.