Motor Height

[Fed]

Until we know what it's doing or not it's a guessing competition.
Could have a spun prop hub, could be running on three cylinders, could be full of fat chicks.

[gazza2006au]

Haha fat chicks rock i love a bit of curvature

Sent from my SM-G900I using Ausfish mobile app

[Noelm]

What the max RPM as it's setup now?

[gazza2006au]

Shakey maybe take the hydrofoil off and drop it one hole and see how she performs?

Sent from my SM-G900I using Ausfish mobile app

[shakey55]

What the max RPM as it's setup now?

Noelm. RPM about 5250 from memory.

I’ve decided not to move the motor. Get back from mechanic after service and do some trials on flat water.

I’ll video the trials and then talk to the experts (Ausfish) and show to my mechanic and see what we come up with.


Sent from my iPhone using Ausfish mobile app

[shakey55]

Shakey maybe take the hydrofoil off and drop it one hole and see how she performs?

Sent from my SM-G900I using Ausfish mobile app

Gazza going to do some more trials before changing anything. Thanks


Sent from my iPhone using Ausfish mobile app

[giddyup58]

I'd take the foil off and try it again.
Make sure your prop is in good condition - no nicks, dings ar bends. It's surprising how what appears to be inconsequential damage can have quite drastic effects...
Trim it right in and nail it and listen for ventilation. Thats where it revs without drive... Put it into hard power turns and listen for ventilation. If it's ventilating, its either too high or simply trimmed out too far.
When it is planing, have someone take the wheel and you get down the back and LOOK at the cavitation plate.
If it is slightly under water and covered in spray, the motor is too low. The entire cav plate should be visible from about 4,000rpm on.
Come up only 1 hole at a time.
Similarly, if the cav plate is already clear, drop it down until it is not visible, then come up 1 hole.
By using the above method, my 24' Mustang picked up 4 knots and stopped porpoising.

Using the same method on the 1600SO and the Ventura helped top speed and fuel economy. None of the boats need a foil.

We found that the Mercury Laser2 propeller can take a lot of engine height. Yours may not be the same, but what I have described above is THE method to set engine height.

You may or may not need the foil, but at least you will know that engine height is not the cause of your problem...

[shakey55]

I'd take the foil off and try it again.
Make sure your prop is in good condition - no nicks, dings ar bends. It's surprising how what appears to be inconsequential damage can have quite drastic effects...
Trim it right in and nail it and listen for ventilation. Thats where it revs without drive... Put it into hard power turns and listen for ventilation. If it's ventilating, its either too high or simply trimmed out too far.
When it is planing, have someone take the wheel and you get down the back and LOOK at the cavitation plate.
If it is slightly under water and covered in spray, the motor is too low. The entire cav plate should be visible from about 4,000rpm on.
Come up only 1 hole at a time.
Similarly, if the cav plate is already clear, drop it down until it is not visible, then come up 1 hole.
By using the above method, my 24' Mustang picked up 4 knots and stopped porpoising.

Using the same method on the 1600SO and the Ventura helped top speed and fuel economy. None of the boats need a foil.

We found that the Mercury Laser2 propeller can take a lot of engine height. Yours may not be the same, but what I have described above is THE method to set engine height.

You may or may not need the foil, but at least you will know that engine height is not the cause of your problem...

Thanks giddyup58

Have not been able to do trials. I had the boat down Shoalhaven over Xmas but due to strong winds had to wait then I had the chance was told that they didn’t boats on the Shoalhaven River due to water bombing aircraft using river to fill up.

Got the boat home on Wednesday night and had a little stuff up (see new thread BROKEN SKEG).

Thanks for the tip. Will report back once trials done and video taken.


Shakey - If only I lived near the coast

[gazza2006au]

Shakey u could always make a mould around the chipped skeg and use a JB Weld i have sealed up holes in crankcases on engines using this stuff

Sent from my SM-G900I using Ausfish mobile app

[giddyup58]

Any alloy fabricator an repair the skeg and sand it up nicely for paint.
If it is actually missing, replacement skegs are available on line. Get one of them welded on and t6he hit it with etch prime and rattle can paint......