Prop Change Out

Hi, I have located a used folding Martec prop for my boat (Cal 9.2) Yea ! ! ! I don't have to now spend $650 only $200 Wondering what to watch out for in installing from a fixed prop. Does the end of the shaft have to be changed in anyway? Any holes to be drilled? Appears that a folding prop hangs lower because it extends out of the end of the shaft, where a fixed is a few inches inside from the end of the shaft. Probably does not matter, except the blade diament can be larger. Also, most important, what is the difference in the pitch number. When I asked Martec which would be best for my boat they said 13 x 10 x 1. The one I am considering is a 9 not 10 pitch. What performance will be compromised ? Any help from the cal list is welcome as always. Late, Nick "Jade" Cal 9.2

Nick I just changed my prop on a Cal 2-29 from a 3 blade 12-12 pitch this was good only if I had more power the new Martec 15-10pitch works great.The first ideal choice should 14-13pitch. Martec is very helpful about the size pitch stuff. The Martec will fit your 1" shaft with standard keyway Also check the free play in the blades Martec sells a shim to correct for play this what I have been told. Go to martec web site they have full directions and they are very helpful. Your size and pitch numbers could to far from the ideal match but try it guess and the beauty about these you can get new blades for the hub. My 10 cents Scott 1975 2-29 ng… [at] comcast.net wrote: Hi, I have located a used folding Martec prop for my boat (Cal 9.2) Yea ! ! ! I don't have to now spend $650 only $200 Wondering what to watch out for in installing from a fixed prop. Does the end of the shaft have to be changed in anyway? Any holes to be drilled? Appears that a folding prop hangs lower because it extends out of the end of the shaft, where a fixed is a few inches inside from the end of the shaft. Probably does not matter, except the blade diament can be larger. Also, most important, what is the difference in the pitch number. When I asked Martec which would be best for my boat they said 13 x 10 x 1. The one I am considering is a 9 not 10 pitch. What performance will be compromised ? Any help from the cal list is welcome as always. Late, Nick "Jade" Cal 9.2 --------------------------------- YAHOO! GROUPS LINKS Visit your group "Cal_Boats" on the web. To unsubscribe from this group, send an email to: Ca… [at] yahoogroups.com Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. --------------------------------- --------------------------------- Yahoo! Autos. Looking for a sweet ride? Get pricing, reviews, & more on new and used cars.

On Jan 28, 2006, at 5:04 PM, ng… [at] comcast.net wrote: > Hi, > I have located a used folding Martec prop for my boat (Cal 9.2) > Yea ! ! ! I don't have to now spend $650 only $200 > Wondering what to watch out for in installing from a fixed prop. Make sure it is a genuine Martec. There are imitations, like Michigan wheel. > Does the end of the shaft have to be changed in anyway? Any holes > to be drilled? Appears that a folding prop hangs lower because it > extends out of the end of the shaft, where a fixed is a few inches > inside from the end of the shaft. Probably does not matter, except > the blade diament can be larger. The nut is in the hub of the Martec. > Also, most important, what is the difference in the pitch number. > When I asked Martec which would be best for my boat they said 13 x > 10 x 1. The one I am considering is a 9 not 10 pitch. What > performance will be compromised ? Slower under power. > > Any help from the cal list is welcome as always. > Late, Nick "Jade" Cal 9.2 Mike Kennedy Conquest Cal 40 # 96 > > YAHOO! GROUPS LINKS > > Visit your group "Cal_Boats" on the web. > > To unsubscribe from this group, send an email to: > Ca… [at] yahoogroups.com > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > >

Hi Nick, I am in the same situation. I am switching from a 14-10 2 bladed fixed prop to a 16-9 martec. (got it on e-bay for $50--baby! not too many people bidding on a left turning prop for a volvo diesel). Any how I spoke to both Martec and the local prop shop. Going from a 10 pitch to a 9 pitch should be no big deal, but you may have to rev the engine faster for the same speed on the water. This is oK as long as you are not over-reving. You should have an optimal RPM target for your particular engine. Also every inch of diameter is roughly equivalent to 1 degree in pitch. In my case the motor may run slower for the same speed as it will develop more thrust per rpm (up 2 in diameter and down 1 in pitch) When I spoke to Martec they recommended several combinations of pitch and diameter for my cal31 with a 13hp volvo. If I recall they suggested a 14-12 or a 15-10. You should have at least 15% of the diameter of the prop in clearance between prop and hull. Hopefully you won't have to shorten the shaft to account for the extra length of the folded prop. If this were the case the shaft would need machining. Probably you would shorten the engine end of it. Probably it would be wise to change your cutless bearing while you are at it. Hope this helps Frank -----Original Message----- From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com]On Behalf Of ng… [at] comcast.net Sent: Saturday, January 28, 2006 8:05 PM To: Cal List Subject: [Cal_Boats] Prop Change Out Hi, I have located a used folding Martec prop for my boat (Cal 9.2) Yea ! ! ! I don't have to now spend $650 only $200 Wondering what to watch out for in installing from a fixed prop. Does the end of the shaft have to be changed in anyway? Any holes to be drilled? Appears that a folding prop hangs lower because it extends out of the end of the shaft, where a fixed is a few inches inside from the end of the shaft. Probably does not matter, except the blade diament can be larger. Also, most important, what is the difference in the pitch number. When I asked Martec which would be best for my boat they said 13 x 10 x 1. The one I am considering is a 9 not 10 pitch. What performance will be compromised ? Any help from the cal list is welcome as always. Late, Nick "Jade" Cal 9.2 ---------------------------------------------------------------------------- -- YAHOO! GROUPS LINKS a.. Visit your group "Cal_Boats" on the web. b.. To unsubscribe from this group, send an email to: Ca… [at] yahoogroups.com c.. Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. ---------------------------------------------------------------------------- --