Outbord engine mounting height.

[yamaha140]

Dear all,

I own a Ranieri pathfinder 18 feet with a Yamaha 140 V4 two stroke outboard.

I just got concerned and noticed that the engine cavitation plate is roughly 2 centimeters above the v shape of the hull. I also heard that such cavitation plate has to be aligned exactly with the V shape of the keel. Does anyone can tell me if the boat is losing performance due to such mounting height, or worse if any harm is being done to the outboard please??.

I thank you in advance for your openions,

Regards,

Johann Malta.

[Landlockedpirate]

Originally Posted by yamaha140

Dear all,

I own a Ranieri pathfinder 18 feet with a Yamaha 140 V4 two stroke outboard.

I just got concerned and noticed that the engine cavitation plate is roughly 2 centimeters above the v shape of the hull. I also heard that such cavitation plate has to be aligned exactly with the V shape of the keel. Does anyone can tell me if the boat is losing performance due to such mounting height, or worse if any harm is being done to the outboard please??.

I thank you in advance for your openions,

Regards,

Johann Malta.

2cm on a non performance boat isnt worth worring about, it wont do the engine any harm either.

We have a similar 19ft centre console in the Med, engine is a little high on that as well. As long as everything works just enjoy the boat.

[nugent]

Just dropped a 250 yam on my rib set cav plate 3" above hull line.


You will be. Fine as is

[yamaha140]

HI guys,

Thanks so much for your replies and Landlockedpirate thanks loads for putting my mind at rest.
Landlockedpirate how much knots you make with your 19 footer with your engine if i may ask?
I can only manage 36.5 knots with a 21 pitch alluminium propp and a 37.5 with a stainless steel prop 21 pitch.

Regards,

Johann Malta.

[Landlockedpirate]

We only have a 90hp ETEC on ours and its propped down for load carrying. Runs around 33kts flat out and lightly loaded.

[jyasaki]

The "plate even with the keel" thing is a starting point.

If it ventilates, prop needs to be lower.

If it splashes a lot, needs to be higher.

Alternatively, you can raise it til it starts ventilating (usually in turns), then drop it back down a hole.

jky