Dear boat friends I have a question here:
Which propellers are the best?
I drive a Coronet Seafarer II (built 1972) with 2 Volvo Penta aq 170 engines and Volvo Penta 270 drives. At the moment I have HIGH-SPEED 15x17 propellers mounted. I have the impression that the engine power can not be used properly here. Does anyone have experience in this subject? I would be very pleased to receive constructive feedback, gladly by e-mail.
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Liebe Bootsfreunde ich habe hier eine Frage:
Welche Propeller sind die optimalen?
Ich fahre eine Coronet Seafarer II (Baujahr 1972) mit 2Volvo Penta aq 170 Motoren und Volvo Penta 270 Antrieben. Momentan habe ich HIGH-SPEED 15x17 Propeller montiert. Ich habe den Eindruck, dass die Motorenleistung hier nicht richtig ausgenutzt werden kann. Hat jemand Erfahrung in diesem Thema? Über eine konstruktive Rückmeldung, gerne per Mail freue ich mich sehr.

Hi!

Do you reach max recomended rpm as it is now?

Do you have to much prop slip?

In the Volvo Penta catalog I belive the standard props are called high speed but in 2020 we do not think 20 plus something knots is high speed.

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Thank you very much for your answer,
I can't get the maximum speed right, it should be at. 4.800 - 5.000 rpm, I can reach a maximum of 4.600.
Since I will overhaul the engines, I will leave it with these propellers for the time being and will continue to test the whole thing next season.
Best regards Joachim

I have a 24 Deluxe/Cabin with the same engines and have not gone over 4,500 because it doesn’t feel right, so I wonder the same thing, if there are newer propellers that offer better speed and efficiency.

Yes, the motors should not run at maximum load for long periods. With me it is so, that with an engine a piston ring is defective. This could be an indication for a too strong load possibly by a too strong propeller pitch. However, the engines are built in 1972 so there could be many other reasons.
I will inform myself further, should I receive further information I will post it here.