Repowered Yamaha ME420 to ME432 Powerloss

[keizerh]

I just repowered my 26 foot boot from a Yamaha ME420 19"single prop to a ME 432 with TRP drive (prop pitch unknown)

New engine makes max 3650 RPM
Old one 3400 RPM

New one
Fuel consumption at 3650 RPM is 65 Litres/hour so engine should deliver 320
HP, speed 55 km/hr.

Old one
Fuel consumption at 3650 RPM is 50 Litres/hour so engine should deliver 250
HP, speed 55 km/hr.

Overall fuel consumption is higher at the new engine.
What can be wrong?

Different prop pitch between front and aft prop?
Wrong prop alignment
or..............................

Please help if you can.

keizerh

[Searider]

Speed?

[keizerh]

55kilometres per hour, both engines.
So 75 Horses are vanished

hendrik

[Ezgoing]

Show us some photos.
What does the dealer say?

rgds

[keizerh]

Here is a pic of the Me420 drive

[keizerh]

And here one of the 432 without props
Props of the new one are 22", and mus be running 77 km/hour

[keizerh]

nobody??

hendrik

[codprawn]

What is acceleration like? It could well be down to the props.

[alt]

Are the gear ratio's the same?

[keizerh]

Accelleration is also less.
Fuel consumption is higher over the full range.
drive ratio was 1.5 and now 1.68

drive is still at the recommended height.
sternangle is the recommended 13 degrees

prop pitches are equal for both props.
prop alignment is correct

hendrik