Prop size and shaft size

bowlbuds2 · Post by **bowlbuds2** » Sat Sep 12, 2009 10:03 pm

Hi Guys, I'm new to inboard engines and the Trojan forum and need help. I have a F26 and the prop on it looks very small. What size, pitch ans shaft size do I need. I have a 318 in her that runs great but she moves real slow. the bottom is clean so I think I have a prop problem. Pease help. Thanks,Bruce

prowlersfish · Post by **prowlersfish** » Sat Sep 12, 2009 11:21 pm

How many rpm can you get at WOT ?

Most likey your boat has a 1 to 1 gear and 1" shaft and came with a 13x10 or maybe a 14X10 prop .

MattSC · Post by **MattSC** » Sun Sep 13, 2009 12:00 am

The prop should be in the neighborhood of a 14x10 with a cup. Your shaft if original should be 1". The recommended WOT for the Chrysler 318 is 4000 rpm. With that setup you should be able to cruise around 17kts and reach 25 at WOT.

bowlbuds2 · Post by **bowlbuds2** » Sun Sep 13, 2009 8:03 am

Thanks for your replies. What does WOT stand for? At 3000 RPM I can only do around 10 MPH. Bruce

LSP · Post by **LSP** » Sun Sep 13, 2009 8:12 am

Wide Open Trottle

g36 · Post by **g36** » Sun Sep 13, 2009 8:43 pm

one thing also to check would be to make sure the mechanical advance in the distributor is working properly.. i thought my 318 was running good till i got to wondering why i was only getting 2900 rpms out of one engine at wot and the other apx 3900 rpms. my boat is a f32 with 2 318's so i had some idea that something was wrong. i got to checking some things and found out that the distributor was the problem. this only surfaced at speed. it would start up run great but had no power. turns out one advance spring was gone and the other stretched. found some springs and installed them and retimed it ,now getting the appropriate rpms. just my thoughts good luck

bowlbuds2 · Post by **bowlbuds2** » Sun Sep 13, 2009 10:04 pm

Thanks again. You guys are great to take time to help. I will check and retry. Thanks , Bruce