[C320-list] C320 Prop Question

[Jeff Hare]

Hi Frank,

Your hull number is really important here, but 15" is the correct prop diameter. The pitch depends on your engine and trans gear ratio. 

Unused fuel coming out would concern me some. If its a yanmar, check the top of the engine to be sure the decompression levers are all in the down position. Can't imagine that one is up, but it should be burning all the fuel I would think.

What boat speed did you reach?

What RPM were you able to reach when you said it was running fast? 3GM should run 3500-3800 rpm or so wide open.

Jeff
C320 #809 -2001. Stock 3blade was 15x9 (LH rotation?)

Frank Reid <freid59 at verizon.net> wrote:

I'm in the process of buying a Catalina 320 and the current owner changed the prop from the 2 blade 13 inch (measured tip to tip) with a 3 blade 15 inch. During our sea trial while under high RPM the engine was expelling unused fuel out the exhaust. If we place the transmission in neutral and rev'd it up there was no fuel expelling. I suspect the prop is the wrong size. It has the 30F engine. Does anyone know for sure what size 3 blade prop is correct?