Volvo Penta DPX prop position
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Anyone know if the Front and Rear prop on the VP DPX drive have a required rotational position relative to one another?
I'm reinstalling my props and can match the previously installed position, but I don't know if they had been installed correctly.
Thanks,
Jeff
I'm reinstalling my props and can match the previously installed position, but I don't know if they had been installed correctly.
Thanks,
Jeff
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Interesting. On Merc Bravo 3's it is very important that they are positioned perfectly.i.e..the blades on the rear prop must cover the spaces between the blades on the front prop.Off even a little and you lose performance and get cavitation.Strange that it doesn't matter on Volvos.
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Interesting. On Merc Bravo 3's it is very important that they are positioned perfectly.i.e..the blades on the rear prop must cover the spaces between the blades on the front prop.Off even a little and you lose performance and get cavitation.Strange that it doesn't matter on Volvos.
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Absolutely. There is even a service bulletin from Merc from years ago with a drawing of how they are positioned.A few years ago we had a customer complaining about reduced performance.Turns out he removed his props to paint the drive,just stuck them back on without alignement,lost a few mph. Ask any Merc dealer,it is fact.
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It's a matter of what position they are in when the path of water off of the front blade intersects the leading edge of the rear blade. Maybe it has something to do with the skegs. DPX's have a relatively small and thin skeg.
Nonetheless, it could make for an intersting experiment. Anyone have a copy of the Mercury bulletin?
Nonetheless, it could make for an intersting experiment. Anyone have a copy of the Mercury bulletin?
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Absolutely. There is even a service bulletin from Merc from years ago with a drawing of how they are positioned.A few years ago we had a customer complaining about reduced performance.Turns out he removed his props to paint the drive,just stuck them back on without alignement,lost a few mph. Ask any Merc dealer,it is fact.
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I used to have a Volvo Duo-Prop on a Cobalt (DPS model) and you had to mount them so that the front and rear prop blades never lined up with the anti-ventilation plate at the same time. VERY IMPORTANT according to Cobalt. I always did it that way but never tried not to.