Prop Causing Engine To Smoke

[Steve Sayian]

I have an M35B on a '99 MKII.  Last year I put on a Kiwi 16" feathering prop with a factory setting of 21 degrees (~11.5").  When the boat was launched the engine lost 600 RPMs and it smoked very bad.  I had a diver go in and reduce the pitch to 18 degrees (~10+").  Engine performance improved but there was still some light grey smoke at the top end.
This year I further reduced the pitch to 17 degrees (~9.5").  Engine RPMs increased a bit (my tach is not at all accurate so revs I achieved are not relevant.  Ordered a laser tach to rectify that problem) and it still smoked light grey smoke at the top end.

Prior to the Kiwi prop I was running the standard 15x9 3-blade Michgan prop and the engine didn't smoke a bit.  Could get 7.1 knots at full throttle.

My transmission is a 1.79:1

My questions are:  1. Does anyone else runnig a Kiwi on an M35B exibit any of these symptoms.
2.  What did your Kiwi props come set with for pitch in degrees?
3.  What diameter Kiwi are you running.

Thanks for the help.

Steve

[Ron Hill]

Steve : Catalina recommends that only a 15" diameter prop be used!!   

[Mike Vaccaro]

We're running a 15 inch Kiwi on our M-25.  You're on the right track with the pitch, but you've got some extra area with 16 inch blades.  Provided blade clearance isn't an issue (Ron's correct about factory recommendation for 15 inch diameter).  The Kiwi dealer will likely swap blades with you, or you can continue to back off the pitch.

Best of luck,

Mike

[Steve Sayian]

Mike,

I checked my paperwork from the company I bought the prop from and it does say 16".

Going to call them tomorrow and see about getting 15" blades.

Thanks to you and Ron for the feedback.

Steve