Prop Question

My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL

Prop QuestionHi John - send me the maximum diameter prop that will fit your boat, and her waterline length, I will get you a prop recommendation. Joe DeMers Sound Marine Diesel LLC www.soundmarinediesel.com ----- Original Message ----- From: John To: Ca… [at] yahoogroups.com Sent: Friday, March 07, 2008 6:44 AM Subject: [Cal_Boats] Prop Question My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL ------------------------------------------------------------------------------ No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.21.3/1306 - Release Date: 3/1/2008 5:41 PM

John, If you are just looking for a new or used prop, check the local prop shops. You may find a fixed three blade some power boater changed to maximize, power, fuel economy etc. Joe should be able to give you the pitch required, and a prop shop can re-pitch a new or used 2 inches or so as needed. Happy hunting. John From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of John Sent: Friday, March 07, 2008 6:45 AM To: Ca… [at] yahoogroups.com Subject: [SPAM][Cal_Boats] Prop Question My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL

Joe- Thanks, I will try and get the dimensions this weekend. John _____ From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of Joe DeMers Sent: Friday, March 07, 2008 7:11 AM To: Ca… [at] yahoogroups.com Subject: Re: [Cal_Boats] Prop Question Hi John - send me the maximum diameter prop that will fit your boat, and her waterline length, I will get you a prop recommendation. Joe DeMers Sound Marine Diesel LLC www.soundmarinedies <http://www.soundmarinediesel.com> el.com From: John <mailto:st… [at] embarqmail.com> To: Cal_Boats@yahoogrou <mailto:Ca… [at] yahoogroups.com> ps.com Sent: Friday, March 07, 2008 6:44 AM Subject: [Cal_Boats] Prop Question My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL _____ No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.21.3/1306 - Release Date: 3/1/2008 5:41 PM

John, My CAL 2-29 has the same serious prop walk to starboard as well. I have a Martec two bladed folding prop. What I have learned to do is, get the boat moving in reverse, it should take 5-10 ft to get enough water over the rudder. Now put the tranny in neutral and the rudder will take over. I don't know your slip arrangement, you might have to practice a few times to get it right. Since I started doing this, I can back down some distance just by putting the tranny in reverse to get it moving and neutral to get control of it. I have been asked what kind of prop I have cause others can't get their boats to back straight. Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and they have the same problem. Dave even did a 360 in his fairlane while trying to get out one day. So I don't know if your new prorp will kill all the prop walk. But you can still try reverse and neutral. Randy CAL 2-29 Out Patient Channel Islands Ca John <st… [at] embarqmail.com> wrote: My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search.

I have a Cal29 and looking into a two blade prop. What size is yours. This will help me not have to dive into the San Francsico Bay "cold" or haul the boat. Thanks Randy Alcorn <sa… [at] yahoo.com> wrote: John, My CAL 2-29 has the same serious prop walk to starboard as well. I have a Martec two bladed folding prop. What I have learned to do is, get the boat moving in reverse, it should take 5-10 ft to get enough water over the rudder. Now put the tranny in neutral and the rudder will take over. I don't know your slip arrangement, you might have to practice a few times to get it right. Since I started doing this, I can back down some distance just by putting the tranny in reverse to get it moving and neutral to get control of it. I have been asked what kind of prop I have cause others can't get their boats to back straight. Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and they have the same problem. Dave even did a 360 in his fairlane while trying to get out one day. So I don't know if your new prorp will kill all the prop walk. But you can still try reverse and neutral. Randy CAL 2-29 Out Patient Channel Islands Ca John <st… [at] embarqmail.com> wrote: My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search.

My old prop with an Atomic 4 is a 12D X 5P. He changed the pitch on my new one, I have lower RPMs and instead of 2.8 at Idle, I am moving 3.2 now. Randy scott cyphers <sc… [at] sbcglobal.net> wrote: I have a Cal29 and looking into a two blade prop. What size is yours. This will help me not have to dive into the San Francsico Bay "cold" or haul the boat. Thanks Randy Alcorn <sa… [at] yahoo.com> wrote: John, My CAL 2-29 has the same serious prop walk to starboard as well. I have a Martec two bladed folding prop. What I have learned to do is, get the boat moving in reverse, it should take 5-10 ft to get enough water over the rudder. Now put the tranny in neutral and the rudder will take over. I don't know your slip arrangement, you might have to practice a few times to get it right. Since I started doing this, I can back down some distance just by putting the tranny in reverse to get it moving and neutral to get control of it. I have been asked what kind of prop I have cause others can't get their boats to back straight. Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and they have the same problem. Dave even did a 360 in his fairlane while trying to get out one day. So I don't know if your new prorp will kill all the prop walk. But you can still try reverse and neutral. Randy CAL 2-29 Out Patient Channel Islands Ca John <st… [at] embarqmail.com> wrote: My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search. --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search.

I have a Beta Marine 13 HP. Does that model number mean it is 12 in? When I search that number it doesn't come back with anything. Thanks for the info. Scott Randy Alcorn <sa… [at] yahoo.com> wrote: My old prop with an Atomic 4 is a 12D X 5P. He changed the pitch on my new one, I have lower RPMs and instead of 2.8 at Idle, I am moving 3.2 now. Randy scott cyphers <sc… [at] sbcglobal.net> wrote: I have a Cal29 and looking into a two blade prop. What size is yours. This will help me not have to dive into the San Francsico Bay "cold" or haul the boat. Thanks Randy Alcorn <sa… [at] yahoo.com> wrote: John, My CAL 2-29 has the same serious prop walk to starboard as well. I have a Martec two bladed folding prop. What I have learned to do is, get the boat moving in reverse, it should take 5-10 ft to get enough water over the rudder. Now put the tranny in neutral and the rudder will take over. I don't know your slip arrangement, you might have to practice a few times to get it right. Since I started doing this, I can back down some distance just by putting the tranny in reverse to get it moving and neutral to get control of it. I have been asked what kind of prop I have cause others can't get their boats to back straight. Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and they have the same problem. Dave even did a 360 in his fairlane while trying to get out one day. So I don't know if your new prorp will kill all the prop walk. But you can still try reverse and neutral. Randy CAL 2-29 Out Patient Channel Islands Ca John <st… [at] embarqmail.com> wrote: My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search. --------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search.

Randy that's a perfect description of what works best. Prop walk is very hard to master in a down windy slip. One day it was blowing about steady 24 in the marina, I had my 16 year old son push me back as fast as he could...all 8000 lbs. out of the slip he hops on the bow. I did the reverse...walk...neutral....reverse, I kept getting pushed down when I would go forward. I couldn't make it. I so I used the prop walk to my advantage and came all the way around to starboard. Sometimes you just have to do what works in the moment! Mark Cal 2-29 San Pedro ----- Original Message ----- From: Randy Alcorn To: Ca… [at] yahoogroups.com Sent: Friday, March 07, 2008 3:40 PM Subject: Re: [Cal_Boats] Prop Question (Scott) My old prop with an Atomic 4 is a 12D X 5P. He changed the pitch on my new one, I have lower RPMs and instead of 2.8 at Idle, I am moving 3.2 now. Randy scott cyphers <sc… [at] sbcglobal.net> wrote: I have a Cal29 and looking into a two blade prop. What size is yours. This will help me not have to dive into the San Francsico Bay "cold" or haul the boat. Thanks Randy Alcorn <sa… [at] yahoo.com> wrote: John, My CAL 2-29 has the same serious prop walk to starboard as well. I have a Martec two bladed folding prop. What I have learned to do is, get the boat moving in reverse, it should take 5-10 ft to get enough water over the rudder. Now put the tranny in neutral and the rudder will take over. I don't know your slip arrangement, you might have to practice a few times to get it right. Since I started doing this, I can back down some distance just by putting the tranny in reverse to get it moving and neutral to get control of it. I have been asked what kind of prop I have cause others can't get their boats to back straight. Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and they have the same problem. Dave even did a 360 in his fairlane while trying to get out one day. So I don't know if your new prorp will kill all the prop walk. But you can still try reverse and neutral. Randy CAL 2-29 Out Patient Channel Islands Ca John <st… [at] embarqmail.com> wrote: My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL -------------------------------------------------------------------------- Looking for last minute shopping deals? Find them fast with Yahoo! Search. ------------------------------------------------------------------------------ Looking for last minute shopping deals? Find them fast with Yahoo! Search. __________ Information from ESET NOD32 Antivirus, version of virus signature database 2930 (20080307) __________ The message was checked by ESET NOD32 Antivirus. http://www.eset.com

After putting the 13" x 9P Gori two-blade folding prop on our 2-29, there is NO prop walk anymore. Backs up perfectly straight and is steerable while in gear. On Mar 7, 2008, at 5:33 PM, Mark Alan Stahnke ((MAS Consulting)) wrote: > > Randy that's a perfect description of what works best. Prop walk is > very hard to master in a down windy slip. One day it was blowing > about steady 24 in the marina, I had my 16 year old son push me > back as fast as he could...all 8000 lbs. out of the slip he hops on > the bow. I did the reverse...walk...neutral....reverse, I kept > getting pushed down when I would go forward. I couldn't make it. I > so I used the prop walk to my advantage and came all the way around > to starboard. Sometimes you just have to do what works in the moment! > Mark Cal 2-29 San Pedro > ----- Original Message ----- > From: Randy Alcorn > To: Ca… [at] yahoogroups.com > Sent: Friday, March 07, 2008 3:40 PM > Subject: Re: [Cal_Boats] Prop Question (Scott) > > > My old prop with an Atomic 4 is a 12D X 5P. > > He changed the pitch on my new one, I have lower RPMs and instead > of 2.8 at Idle, I am moving 3.2 now. > > Randy > > > scott cyphers <sc… [at] sbcglobal.net> wrote: > I have a Cal29 and looking into a two blade prop. What size is > yours. This will help me not have to dive into the San Francsico > Bay "cold" or haul the boat. Thanks > > Randy Alcorn <sa… [at] yahoo.com> wrote: > John, > > My CAL 2-29 has the same serious prop walk to starboard as well. I > have a Martec two bladed folding prop. > > What I have learned to do is, get the boat moving in reverse, it > should take 5-10 ft to get enough water over the rudder. Now put > the tranny in neutral and the rudder will take over. > > I don't know your slip arrangement, you might have to practice a > few times to get it right. > Since I started doing this, I can back down some distance just by > putting the tranny in reverse to get it moving and neutral to get > control of it. > > I have been asked what kind of prop I have cause others can't get > their boats to back straight. > > Dave & Bill's, CAL 3-34 Alegria(sp?) has a 3 blade fixed prop and > they have the same problem. Dave even did a 360 in his fairlane > while trying to get out one day. > > So I don't know if your new prorp will kill all the prop walk. But > you can still try reverse and neutral. > > > Randy > CAL 2-29 > Out Patient > Channel Islands Ca > > > > John <st… [at] embarqmail.com> wrote: > My Cal 31 has always had a serious starboard prop walk (apparently > standard from reading this list over the years) However, it seems > to be even worse after my last bottom job and I'm wondering if this > can be exacerbated by prop or rudder problems. > Also, can anybody recommend an inexpensive prop and source (13HP > Volvo Penta, currently with a two blade). > Thanks in advance, > John Stacklyn > Cal 31 #33 "Sol Survivor" > Shell Point, FL > > > Looking for last minute shopping deals? Find them fast with Yahoo! > Search. > > > > Looking for last minute shopping deals? Find them fast with Yahoo! > Search. > > > > __________ Information from ESET NOD32 Antivirus, version of virus > signature database 2930 (20080307) __________ > > The message was checked by ESET NOD32 Antivirus. > > http://www.eset.com > > Richard Anderson President, Charity Through Youthful Living ri… [at] ctyl.org

Mark Alan Stahnke (MAS Consulting) wrote: > > Randy that's a perfect description of what works best. Prop walk is > very hard to master in a down windy slip. One day it was blowing about > steady 24 in the marina, I had my 16 year old son push me back as fast > as he could...all 8000 lbs. out of the slip he hops on the bow. I did > the reverse...walk...neutral....reverse, I kept getting pushed down > when I would go forward. I couldn't make it. I so I used the prop > walk to my advantage and came all the way around to starboard. > Sometimes you just have to do what works in the moment! My other boat has a newer outboard with the gear shift in the throttle handle. Boy, did that thing take some getting used to. I'd back out (in neutral, after goosing it in R) and then hit forward (I thought). Sometimes I guessed wrong and things got rather exciting. I did a few circles in the slip while hoping nobody was looking! Chris

Joe, My Cal 31 LWL is 25'- 8" and the maximum diameter prop would be about 16". It has a Volvo Penta 13 H.P. and a 2-bladed prop of around 13" of unknown pitch. I think it may be bent or somehow out-of-whack, as the prop walk to starboard seems much worse since my last bottom job and I can't think of anything else. Thanks! John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL _____ From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of John Sent: Friday, March 07, 2008 3:38 PM To: Ca… [at] yahoogroups.com Subject: RE: [Cal_Boats] Prop Question (Joe D.) Joe- Thanks, I will try and get the dimensions this weekend. John _____ From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of Joe DeMers Sent: Friday, March 07, 2008 7:11 AM To: Ca… [at] yahoogroups.com Subject: Re: [Cal_Boats] Prop Question Hi John - send me the maximum diameter prop that will fit your boat, and her waterline length, I will get you a prop recommendation. Joe DeMers Sound Marine Diesel LLC www.soundmarinedies <http://www.soundmarinediesel.com> el.com From: John <mailto:st… [at] embarqmail.com> To: Cal_Boats@yahoogrou <mailto:Ca… [at] yahoogroups.com> ps.com Sent: Friday, March 07, 2008 6:44 AM Subject: [Cal_Boats] Prop Question My Cal 31 has always had a serious starboard prop walk (apparently standard from reading this list over the years) However, it seems to be even worse after my last bottom job and I'm wondering if this can be exacerbated by prop or rudder problems. Also, can anybody recommend an inexpensive prop and source (13HP Volvo Penta, currently with a two blade). Thanks in advance, John Stacklyn Cal 31 #33 "Sol Survivor" Shell Point, FL _____ No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.5.516 / Virus Database: 269.21.3/1306 - Release Date: 3/1/2008 5:41 PM

--- In Ca… [at] yahoogroups.com, "John" <stacklynj@...> wrote: > > Joe, > My Cal 31 LWL is 25'- 8" and the maximum diameter prop would be about 16". > It has a Volvo Penta 13 H.P. and a 2-bladed prop of around 13" of unknown > pitch. I think it may be bent or somehow out-of-whack, as the prop walk to > starboard seems much worse since my last bottom job and I can't think of > anything else. > Thanks! > > John Stacklyn > Cal 31 #33 "Sol Survivor" > Shell Point, FL > > > _____ > John, Just a follow up. Did you make a prop investment? Did Joe D recomend something for your 31? What did you get, and how well does it work? Thanks Patrick Cal 31 #118 Windchaser

I am facing a decision on my prop. As part of getting my Grey Marine 4-112 rebuilt I need to also do something with the old Martec folding prop as my diver says it needs servicing, which I have never done. I need to decide repair or replace on the prop. One of the questions I have is do I have the best size prop. Without actually knowing what size the existing prop is, this is really a difficult question but I do have a fair amount of information. Here is what I know: - Lapworth specified 14RH8 on the blueprint for the L-36 - The 3 blade that was on the boat when I got it was a 13RH9 - I removed the 3 blade and installed the Martec folding that was in the lazarette. - I dove to measure the prop and it measured 14 inches with an angle at 2/3 or the way out of 11-16 degrees which would mean a pitch in the 6 to 8 range. Not that close a measurement I know. - The Grey Marine Engine manual suggests 14x9 or 13x10 for that size engine (no mention of boat size or power vs sail) - Engine vs Boat Speed with existing prop: - 1500 - 5.7kt - 1250 - 4.9kt - 1000 - 3.6kt - 750 - 2.4kt - The above measurements were taken with my old worn out engine which has 40 psi compression. It ran fine. - I have a vague memory of seeing a graph my dad did showing the boat was faster at any given RPM with the fixed blade. - Cruising RPM per my mechanic is around 1300 - Maximum HP 31@2200RPM per engine manual - Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish - New Prop of newer design $710 + shipping + labor? = $750ish - I put 30 hrs a year on the engine, basically only race or go to races. I just say this to point out I need a low drag prop. Rebuilding is cheaper but if I am told the more modern design backs up better, whatever that means. There is no way I could back up worse as I can't back up at all. All reverse is good for is stopping the boat and does that well with no problems. I blame the offset prop that sits above the rudder so there is no backwash against the rudder for the backing problems although I am told that isn't correct, another story. The other question is, with the information above, do I have the right prop on the boat now? If I can get better performance with a new prop, this would be the time to get it. There are basically two ways that it might be worth getting a new prop - Better backing which I have to take either on faith or from testimonial from one of you - Better boat speed because the results above indicate I have the wrong prop pitch Any thoughts? Joe??? Others??? Allen

Start here - max diameter prop that will fit the boat. Load waterline of hull engine hp @ what? rpm reduction gear ratio. Send that info, and I will get you a prop recommendation. _*/*) *Joe DeMers - owner* Sound Marine Diesel LLC SoundMarineDiesel.com <http://www.soundmarinediesel.com/> *phone & fax (860) 666-2184* On 2/24/2012 11:32 AM, Allen Edwards wrote: > > > > I am facing a decision on my prop. As part of getting my Grey Marine > 4-112 rebuilt I need to also do something with the old Martec folding > prop as my diver says it needs servicing, which I have never done. I > need to decide repair or replace on the prop. One of the questions I > have is do I have the best size prop. Without actually knowing what > size the existing prop is, this is really a difficult question but I > do have a fair amount of information. Here is what I know: > > * Lapworth specified 14RH8 on the blueprint for the L-36 > * The 3 blade that was on the boat when I got it was a 13RH9 > * I removed the 3 blade and installed the Martec folding that was > in the lazarette. > * I dove to measure the prop and it measured 14 inches with an > angle at 2/3 or the way out of 11-16 degrees which would mean a > pitch in the 6 to 8 range. Not that close a measurement I know. > * The Grey Marine Engine manual suggests 14x9 or 13x10 for that > size engine (no mention of boat size or power vs sail) > * Engine vs Boat Speed with existing prop: > * 1500 - 5.7kt > * 1250 - 4.9kt > * 1000 - 3.6kt > * 750 - 2.4kt > * The above measurements were taken with my old worn out engine > which has 40 psi compression. It ran fine. > * I have a vague memory of seeing a graph my dad did showing the > boat was faster at any given RPM with the fixed blade. > * Cruising RPM per my mechanic is around 1300 > * Maximum HP 31@2200RPM per engine manual > * Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish > * New Prop of newer design $710 + shipping + labor? = $750ish > * I put 30 hrs a year on the engine, basically only race or go to > races. I just say this to point out I need a low drag prop. > > Rebuilding is cheaper but if I am told the more modern design backs up > better, whatever that means. There is no way I could back up worse as > I can't back up at all. All reverse is good for is stopping the boat > and does that well with no problems. I blame the offset prop that > sits above the rudder so there is no backwash against the rudder for > the backing problems although I am told that isn't correct, another story. > > The other question is, with the information above, do I have the right > prop on the boat now? If I can get better performance with a new > prop, this would be the time to get it. There are basically two ways > that it might be worth getting a new prop > > * Better backing which I have to take either on faith or from > testimonial from one of you > * Better boat speed because the results above indicate I have the > wrong prop pitch > > Any thoughts? Joe??? Others??? > > Allen > > > > > No virus found in this message. > Checked by AVG - www.avg.com <http://www.avg.com> > Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 > -- *Joe DeMers - owner* Sound Marine Diesel LLC SoundMarineDiesel.com <http://www.soundmarinediesel.com/> *phone & fax (860) 666-2184*

Thanks Joe, The L-36 has a designed LWL of 28 feet. I have not measured the actual. The engine HP is 31 @ 2200 RPM but I have been told to run it closer to 1200-1300 RPM. Design weight is 12000 pounds. The gearbox is 1:1. The boat specification is 14 inch prop and that is what is on there now so I want to stick with that size. It is also larger than the 13RH9 3 blade I took off the boat. I want a folding prop, likely a 2 blade non-geared Martec. Allen PS. I see lots of hits to your article on my web site. If you ever write another I would love to post it. On Fri, Feb 24, 2012 at 8:53 AM, Joe DeMers <je… [at] mindspring.com> wrote: > ** > > > ** Start here - > > max diameter prop that will fit the boat. > > Load waterline of hull > > engine hp @ what? rpm > > reduction gear ratio. > > > > Send that info, and I will get you a prop recommendation. > > _*/*) > *Joe DeMers - owner* > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184* > > > On 2/24/2012 11:32 AM, Allen Edwards wrote: > > > I am facing a decision on my prop. As part of getting my Grey Marine > 4-112 rebuilt I need to also do something with the old Martec folding prop > as my diver says it needs servicing, which I have never done. I need to > decide repair or replace on the prop. One of the questions I have is do I > have the best size prop. Without actually knowing what size the existing > prop is, this is really a difficult question but I do have a fair amount of > information. Here is what I know: > > - Lapworth specified 14RH8 on the blueprint for the L-36 > - The 3 blade that was on the boat when I got it was a 13RH9 > - I removed the 3 blade and installed the Martec folding that was in > the lazarette. > - I dove to measure the prop and it measured 14 inches with an angle > at 2/3 or the way out of 11-16 degrees which would mean a pitch in the 6 to > 8 range. Not that close a measurement I know. > - The Grey Marine Engine manual suggests 14x9 or 13x10 for that size > engine (no mention of boat size or power vs sail) > - Engine vs Boat Speed with existing prop: > - 1500 - 5.7kt > - 1250 - 4.9kt > - 1000 - 3.6kt > - 750 - 2.4kt > - The above measurements were taken with my old worn out engine which > has 40 psi compression. It ran fine. > - I have a vague memory of seeing a graph my dad did showing the boat > was faster at any given RPM with the fixed blade. > - Cruising RPM per my mechanic is around 1300 > - Maximum HP 31@2200RPM per engine manual > - Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish > - New Prop of newer design $710 + shipping + labor? = $750ish > - I put 30 hrs a year on the engine, basically only race or go to > races. I just say this to point out I need a low drag prop. > > Rebuilding is cheaper but if I am told the more modern design backs up > better, whatever that means. There is no way I could back up worse as I > can't back up at all. All reverse is good for is stopping the boat and > does that well with no problems. I blame the offset prop that sits above > the rudder so there is no backwash against the rudder for the backing > problems although I am told that isn't correct, another story. > > The other question is, with the information above, do I have the right > prop on the boat now? If I can get better performance with a new prop, > this would be the time to get it. There are basically two ways that it > might be worth getting a new prop > > - Better backing which I have to take either on faith or from > testimonial from one of you > - Better boat speed because the results above indicate I have the > wrong prop pitch > > Any thoughts? Joe??? Others??? > > Allen > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 > > > -- > > *Joe DeMers - owner* > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184* > > >

14 x 8, 2 blade, RH. If you increase the pitch 1", the rpm will drop by 200 . [ the engine will then make 2000 rpm ] . Your boat speed is restricted to 7 knots under power, according to your LWL dimension. You will need to run the engine close to maximum rpm to get that theoretical 7 knots. Thanks Allen, for the comments concerning my repowering article. I would like to write another, but on what subject? _*/*) *Joe DeMers - owner* Sound Marine Diesel LLC SoundMarineDiesel.com <http://www.soundmarinediesel.com/> *phone & fax (860) 666-2184* On 2/24/2012 12:10 PM, Allen Edwards wrote: > > > Thanks Joe, > > The L-36 has a designed LWL of 28 feet. I have not measured the > actual. The engine HP is 31 @ 2200 RPM but I have been told to run it > closer to 1200-1300 RPM. Design weight is 12000 pounds. The > gearbox is 1:1. The boat specification is 14 inch prop and that is > what is on there now so I want to stick with that size. It is also > larger than the 13RH9 3 blade I took off the boat. I want a folding > prop, likely a 2 blade non-geared Martec. > > Allen > > PS. I see lots of hits to your article on my web site. If you ever > write another I would love to post it. > > > On Fri, Feb 24, 2012 at 8:53 AM, Joe DeMers <je… [at] mindspring.com > <mailto:je… [at] mindspring.com>> wrote: > > Start here - > > max diameter prop that will fit the boat. > > Load waterline of hull > > engine hp @ what? rpm > > reduction gear ratio. > > > > Send that info, and I will get you a prop recommendation. > > _*/ * ) > > *Joe DeMers - owner * > > Sound Marine Diesel LLC > > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184 <tel:%28860%29%20666-2184> * > > > > On 2/24/2012 11:32 AM, Allen Edwards wrote: >> >> I am facing a decision on my prop. As part of getting my Grey >> Marine 4-112 rebuilt I need to also do something with the old >> Martec folding prop as my diver says it needs servicing, which I >> have never done. I need to decide repair or replace on the prop. >> One of the questions I have is do I have the best size prop. >> Without actually knowing what size the existing prop is, this is >> really a difficult question but I do have a fair amount of >> information. Here is what I know: >> >> * Lapworth specified 14RH8 on the blueprint for the L-36 >> * The 3 blade that was on the boat when I got it was a 13RH9 >> * I removed the 3 blade and installed the Martec folding that >> was in the lazarette. >> * I dove to measure the prop and it measured 14 inches with >> an angle at 2/3 or the way out of 11-16 degrees which would >> mean a pitch in the 6 to 8 range. Not that close a >> measurement I know. >> * The Grey Marine Engine manual suggests 14x9 or 13x10 for >> that size engine (no mention of boat size or power vs sail) >> * Engine vs Boat Speed with existing prop: >> * 1500 - 5.7kt >> * 1250 - 4.9kt >> * 1000 - 3.6kt >> * 750 - 2.4kt >> * The above measurements were taken with my old worn out >> engine which has 40 psi compression. It ran fine. >> * I have a vague memory of seeing a graph my dad did showing >> the boat was faster at any given RPM with the fixed blade. >> * Cruising RPM per my mechanic is around 1300 >> * Maximum HP 31@2200RPM per engine manual >> * Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish >> * New Prop of newer design $710 + shipping + labor? = $750ish >> * I put 30 hrs a year on the engine, basically only race or >> go to races. I just say this to point out I need a low >> drag prop. >> >> Rebuilding is cheaper but if I am told the more modern design >> backs up better, whatever that means. There is no way I could >> back up worse as I can't back up at all. All reverse is good for >> is stopping the boat and does that well with no problems. I >> blame the offset prop that sits above the rudder so there is no >> backwash against the rudder for the backing problems although I >> am told that isn't correct, another story. >> >> The other question is, with the information above, do I have the >> right prop on the boat now? If I can get better performance with >> a new prop, this would be the time to get it. There are >> basically two ways that it might be worth getting a new prop >> >> * Better backing which I have to take either on faith or from >> testimonial from one of you >> * Better boat speed because the results above indicate I have >> the wrong prop pitch >> >> Any thoughts? Joe??? Others??? >> >> Allen >> >> No virus found in this message. >> Checked by AVG - www.avg.com <http://www.avg.com> >> Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: >> 02/24/12 >> > > -- > > *Joe DeMers - owner * > > Sound Marine Diesel LLC > > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184 <tel:%28860%29%20666-2184> * > > > > > > > No virus found in this message. > Checked by AVG - www.avg.com <http://www.avg.com> > Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 > -- *Joe DeMers - owner* Sound Marine Diesel LLC SoundMarineDiesel.com <http://www.soundmarinediesel.com/> *phone & fax (860) 666-2184*

..having to put up with scatterbrained engine buyers like Reggie! Thanks Allen, for the comments concerning my repowering article. I would like to write another, but on what subject? _/) Joe DeMers - owner Sound Marine Diesel LLCSoundMarineDiesel.com phone & fax (860) 666-2184 On 2/24/2012 12:10 PM, Allen Edwards wrote: Thanks Joe, The L-36 has a designed LWL of 28 feet. I have not measured the actual. The engine HP is 31 @ 2200 RPM but I have been told to run it closer to 1200-1300 RPM. Design weight is 12000 pounds. The gearbox is 1:1. The boat specification is 14 inch prop and that is what is on there now so I want to stick with that size. It is also larger than the 13RH9 3 blade I took off the boat. I want a folding prop, likely a 2 blade non-geared Martec. Allen PS. I see lots of hits to your article on my web site. If you ever write another I would love to post it. On Fri, Feb 24, 2012 at 8:53 AM, Joe DeMers <je… [at] mindspring.com> wrote: Start here - max diameter prop that will fit the boat. Load waterline of hull engine hp @ what? rpm reduction gear ratio. Send that info, and I will get you a prop recommendation. _ / ) Joe DeMers - owner Sound Marine Diesel LLC SoundMarineDiesel.com phone & fax (860) 666-2184 On 2/24/2012 11:32 AM, Allen Edwards wrote: I am facing a decision on my prop. As part of getting my Grey Marine 4-112 rebuilt I need to also do something with the old Martec folding prop as my diver says it needs servicing, which I have never done. I need to decide repair or replace on the prop. One of the questions I have is do I have the best size prop. Without actually knowing what size the existing prop is, this is really a difficult question but I do have a fair amount of information. Here is what I know: Lapworth specified 14RH8 on the blueprint for the L-36 The 3 blade that was on the boat when I got it was a 13RH9 I removed the 3 blade and installed the Martec folding that was in the lazarette. I dove to measure the prop and it measured 14 inches with an angle at 2/3 or the way out of 11-16 degrees which would mean a pitch in the 6 to 8 range. Not that close a measurement I know. The Grey Marine Engine manual suggests 14x9 or 13x10 for that size engine (no mention of boat size or power vs sail) Engine vs Boat Speed with existing prop: 1500 - 5.7kt 1250 - 4.9kt 1000 - 3.6kt 750 - 2.4kt The above measurements were taken with my old worn out engine which has 40 psi compression. It ran fine. I have a vague memory of seeing a graph my dad did showing the boat was faster at any given RPM with the fixed blade. Cruising RPM per my mechanic is around 1300 Maximum HP 31@2200RPM per engine manual Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish New Prop of newer design $710 + shipping + labor? = $750ish I put 30 hrs a year on the engine, basically only race or go to races. I just say this to point out I need a low drag prop. Rebuilding is cheaper but if I am told the more modern design backs up better, whatever that means. There is no way I could back up worse as I can't back up at all. All reverse is good for is stopping the boat and does that well with no problems. I blame the offset prop that sits above the rudder so there is no backwash against the rudder for the backing problems although I am told that isn't correct, another story. The other question is, with the information above, do I have the right prop on the boat now? If I can get better performance with a new prop, this would be the time to get it. There are basically two ways that it might be worth getting a new prop Better backing which I have to take either on faith or from testimonial from one of you Better boat speed because the results above indicate I have the wrong prop pitch Any thoughts? Joe??? Others??? Allen No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 -- Joe DeMers - owner Sound Marine Diesel LLC SoundMarineDiesel.com phone & fax (860) 666-2184 No virus found in this message. Checked by AVG - www.avg.com Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 -- Joe DeMers - owner Sound Marine Diesel LLCSoundMarineDiesel.com phone & fax (860) 666-2184

How to pick the best prop (variables are several: least drag, most spead, cruiser vs racer vs weekender) for you boat..:) Now that would be a great additional article to the engine install as thats the most logical followup. Also there are a number of related issues, shaft, cutless bearing, alignment, max prop in a given space etc etc. Best regards /ch On Fri, Feb 24, 2012 at 12:36 PM, Joe DeMers <je… [at] mindspring.com> wrote: > ** > > > 14 x 8, 2 blade, RH. If you increase the pitch 1", the rpm will drop by > 200 . [ the engine will then make 2000 rpm ] . Your boat speed is > restricted to 7 knots under power, according to your LWL dimension. > > You will need to run the engine close to maximum rpm to get that > theoretical 7 knots. > > Thanks Allen, for the comments concerning my repowering article. I would > like to write another, but on what subject? > _*/*) > *Joe DeMers - owner* > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184* > > > > On 2/24/2012 12:10 PM, Allen Edwards wrote: > > > > Thanks Joe, > > The L-36 has a designed LWL of 28 feet. I have not measured the actual. > The engine HP is 31 @ 2200 RPM but I have been told to run it closer to > 1200-1300 RPM. Design weight is 12000 pounds. The gearbox is 1:1. The > boat specification is 14 inch prop and that is what is on there now so I > want to stick with that size. It is also larger than the 13RH9 3 blade I > took off the boat. I want a folding prop, likely a 2 blade non-geared > Martec. > > Allen > > PS. I see lots of hits to your article on my web site. If you ever > write another I would love to post it. > > > On Fri, Feb 24, 2012 at 8:53 AM, Joe DeMers <je… [at] mindspring.com>wrote: > > > > Start here - > > max diameter prop that will fit the boat. > > Load waterline of hull > > engine hp @ what? rpm > > reduction gear ratio. > > > > Send that info, and I will get you a prop recommendation. > > _* / * ) > * Joe DeMers - owner * > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > * phone & fax (860) 666-2184 <%28860%29%20666-2184> * > > > On 2/24/2012 11:32 AM, Allen Edwards wrote: > > > I am facing a decision on my prop. As part of getting my Grey Marine > 4-112 rebuilt I need to also do something with the old Martec folding prop > as my diver says it needs servicing, which I have never done. I need to > decide repair or replace on the prop. One of the questions I have is do I > have the best size prop. Without actually knowing what size the existing > prop is, this is really a difficult question but I do have a fair amount of > information. Here is what I know: > > - Lapworth specified 14RH8 on the blueprint for the L-36 > - The 3 blade that was on the boat when I got it was a 13RH9 > - I removed the 3 blade and installed the Martec folding that was in > the lazarette. > - I dove to measure the prop and it measured 14 inches with an angle > at 2/3 or the way out of 11-16 degrees which would mean a pitch in the 6 to > 8 range. Not that close a measurement I know. > - The Grey Marine Engine manual suggests 14x9 or 13x10 for that size > engine (no mention of boat size or power vs sail) > - Engine vs Boat Speed with existing prop: > - 1500 - 5.7kt > - 1250 - 4.9kt > - 1000 - 3.6kt > - 750 - 2.4kt > - The above measurements were taken with my old worn out engine which > has 40 psi compression. It ran fine. > - I have a vague memory of seeing a graph my dad did showing the boat > was faster at any given RPM with the fixed blade. > - Cruising RPM per my mechanic is around 1300 > - Maximum HP 31@2200RPM per engine manual > - Repair prop $210 + shipping ($30) + labor ? ($70) = $310ish > - New Prop of newer design $710 + shipping + labor? = $750ish > - I put 30 hrs a year on the engine, basically only race or go to > races. I just say this to point out I need a low drag prop. > > Rebuilding is cheaper but if I am told the more modern design backs up > better, whatever that means. There is no way I could back up worse as I > can't back up at all. All reverse is good for is stopping the boat and > does that well with no problems. I blame the offset prop that sits above > the rudder so there is no backwash against the rudder for the backing > problems although I am told that isn't correct, another story. > > The other question is, with the information above, do I have the right > prop on the boat now? If I can get better performance with a new prop, > this would be the time to get it. There are basically two ways that it > might be worth getting a new prop > > - Better backing which I have to take either on faith or from > testimonial from one of you > - Better boat speed because the results above indicate I have the > wrong prop pitch > > Any thoughts? Joe??? Others??? > > Allen > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 > > > -- > > * Joe DeMers - owner * > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > * phone & fax (860) 666-2184 <%28860%29%20666-2184> * > > > > > No virus found in this message. > Checked by AVG - www.avg.com > Version: 2012.0.1913 / Virus Database: 2114/4829 - Release Date: 02/24/12 > > > -- > > *Joe DeMers - owner* > > Sound Marine Diesel LLC > SoundMarineDiesel.com <http://www.soundmarinediesel.com/> > > *phone & fax (860) 666-2184* > > > > -- /ch