Prop advice and buy in hurry - KAD42 with 290 DP

[BruceK]

Can anybody advise on the correct prop selection for a 34 foot 7 tonne performance cruiser running twin KAD42's and 290 DP legs? I have no previous experience of duoprops andI'm getting confused over all the A3-5 - D3-5 - C and then B series J series etc etc. It's like shopping for shoes with the wife.

I pulled the boat out for a mid season check and hull clean and the props are mangled. So much for a dirty bottom. The legs etc were but the main culprit were these

Dont ask me when how or where. Got no clue, just noticed a lack of performance that I attributed to fouling.


Can these be repaired? both sets damaged?

Are aluminium props any good as a temporary replacement while these get repaired? (I have a hot date next weekend)

Where can I get in a hurry? Keyparts? http://www.keypart.com/volvo-penta/duoprop-sterndrive/290dp

I see this seems good value for a temp repair but dont really want to risk any further damage if they are not up to scratch http://coastalrides.co.uk/sterndriv...s/a5-duo-propeller-set-replacement-for-854768

 

[BruceK]

I've managed to narrow it down to C3 3587865 or 3860604 for the front prop (the serial 3860604 on the front prop didn't throw any google hits), what does this equate to for ali props?

 

[scottie]

Any reasonable propellor supplier will supply from that number
Any proper repairer will tell you if worth doing

 

[darrenw]

You can cross reference those numbers here...

http://www.volvopenta.com/SiteCollectionDocuments/Penta/Propeller guide/Propeller Guide.pdf

 

[BruceK]

Thanks. Found the matching rear prop for that - 3587871

The set then has a part code of 3588223

Can anybody tell me what the aluminium equivalent of this set is while I get these repaired?

 

[darrenw]

I think you just replace the letter, C being SS and 3 being the size.

Looks like J is the current aluminium equivalent, although A & B went before so they might be ok if you found stock somewhere. Look at the blade profiles for the differences (3 or 4 blades)..

J3 = 21924263

I did notice the following caveat though...

Note! Always use type C stainless steel propellers in engines exceeding 240 hp or capable of speeds above 38 knots (45 mph).

HTH

 

[BruceK]

Oh bother. That's a bit marginal for the KAD42's then.

 

[Seastoke]

why would they make them if you cant use them ,nieve question

 

[BruceK]

The 290 DP outdrive isn't restricted to KAD4xxx use only I suspect.

 

[darrenw]

Nope, that's what i've got on my KAD32 and I'm running with aluminium A6 duo props.

 

[Pendana]

My Targa 35 has Kad42's running on B6 props. I think the Kad 42 develops too much torque for the A series which have a 4 bladed aft prop. The B series has a 3 bladed aft prop.
Probably cant get these any more and now have to for J series.

 

[Seastoke]

whats update bruce

 

[[2068]]

Your current props are "C3" given that 3860604 part number.
Ali equivalent would be roughly "B4" (old style props) or "J5" (new style).

But it's not a precise science: the above suggestions could be out by one size in any direction, depending on the boat.

.