Hi guys i am looking for some info regarding a prop i just bought for my 38 Bav with the MD2040C engine. If any of you have this engine and know what pitch and diameter your Folding prop kindly advise, and also state (of course if you know) what revs the engine reaches a full throttle i.e. the WOT wide open throttle range.
Pitch and diameter does not depend on the engine alone but also on:
the gearbox ratio
engine Horse Power
waterline length of hull
The best option is to look at the size of your VP fixed propeller. It is engraved on the hub.
I just went through this process last November when I had a new 3 blade VP folding fitted. The dealer first calculated the size using the parameters above. Then the size was confirmed when the fixed prop was removed.
However beware: VP currently are having issues with their hubs. Here is my story:
November 2011: ordered new propeller. VP folding come in a kit. The hub is common to all sizes, the blades come separated with specified pitch and diameter.
November 2011: new propeller fitted by VP dealer and relaunched
December 2011: first sea trial, strong vibration running at cruise speeds, quite concerned. Very happy under sail, boat never sailed so fast. Reverse was as expected, loss of thrust compared to fixed prop, but still manageable. The manageability of fin keel + saildrive helps a lot too.
December 2011: second sea trial with dealer. Dealer confirms strong vibration from new VP folding prop
December 2011: dealer makes claim with VP. They agree to replace the prop and pay for lift/relaunch.
January 2012: Dealer receives new propeller kit. Dealer check propeller and finds that hub does not turn true on its axis. Dealer makes second claim with VP and returns the new hub.
January 2012: Dealer receives new replacement hub. Dealer checks this one too. At first looks like it turns true, but further checks reveal that it turns out of its axis by 2mm. Which means the blades would draw an oval rather than a circle. Dealer returns this second hub.
February 2012: still awaiting for my propeller to be replaced.
Do not think that other makes are better: someone I know in the marina had a Brunton fitted: the propeller fell off soon after relaunch. Brunton blamed the dealer. Dealer called a surveyor who reported a manufacturing defect. Brunton eventually refunded the cost of the propeller but refused to pay for lift and relaunch and the dealer's time.
I hope this helps
