C&C 27 Association Forum

pura vida

Member

Yanmar 2 GM Prop Question

Just when I thought that Hurricane Ike had done nothing more than blowing a fender onto my deck it strikes again.

The diver keeping the hull on my boat had removed the prop prior to the storm thinking that he was doing me a favor. I won't bore with the "whys" or "I'll have it back on no later thans", but I will say that the guy is no longer answering his phone. Short of just dropping by his house on the outside chance that he is there I suspect that I will never see my prop again.

So here is the question. I have a Martec right hand folding prop I was planning to install, but I am concerned that I need a left hand prop for this engine. I've checked my original paperwork for the prop I have lost, but with no conclusive information. Can anyone clear this up.

thanks
Mike M
SV Wind Horse
#375
Galveston, Tx

---

Mike M
SV Wind Horse
#375
Galveston, Tx

Guest

Re: Yanmar 2 GM Prop Question

My friend has a 2GM in his C&C 29, and I have a 1GM10 in my C&C 27 Mk V.  I have a right hand Gori.   He has the same prop.  Frankly I didn't check so close as to tell if his was also  right hand, but it sure looked the same to me.

If you go to the Gori site you can type in the boat type and engine type and they will email prop recommendations.  In my case the recommendation specifically said the prop is a right handed one.

Good luck.

Barry, Oasis, 1987 Mk V

Roger Gibb

Member

Re: Yanmar 2 GM Prop Question

Definitely right hand (I have a 2GM on Passtime).

Some other info you may need:

Continuous rating output: 13hp/3400rpm

One hour rating output: 15hp/3600rpm

Reduction ratio: 2.62

Cheers
Roger Gibb
Passtime (27-4)

---

Roger Gibb
Passtime (27-4)

Hugh Morrin

Member

Re: Yanmar 2 GM Prop Question

We bought a new Martec for our 2GM equipped MK III earlier this year. Recommended prop from Martec was a Martec, MK 3 Folding, RH 14" D x 12P-3, 7/8" D shaft. Martec Tech Support were also very helpful -- see http://www.martec-props.com.
Hugh Morrin
Blue Zulu
C&C 27 Mk III, #894
Nepean Sailing Club
www.nsc.ca/cc27
</a>

---

Hugh Morrin
Blue Zulu, C&C 27 Mk III, #894
Nepean Sailing Club, www.nsc.ca/cc27
President and back-up webmaster, C&C 27 Association

pura vida

Member

Re: Yanmar 2 GM Prop Question

Hugh,

How well does the boat handle with the Martec? That is what I am considering and wondered if it is possible to back out of the slip without help.

Thanks
Mike M
SV Wind Horse
#375
Galveston, Tx

---

Mike M
SV Wind Horse
#375
Galveston, Tx

carriden

Member

Re: Yanmar 2 GM Prop Question

Hey Mike,

I have a 13-inch Martec elliptical folding prop (non-geared) on Carriden.  Backing out is a breeze, as is stopping on the way into the slip.  After 4 years, I have total faith in the Martec.

Interestingly, a good friend of mine also has a 27 which, like Carriden, is equipped with an Atomic 4.  However, he uses a fixed-blade prop of 11-inch diameter.  He is so-o-o-o jealous of me because Carriden turns in over 6 knots of speed at 1440 RPM in flat water.  His boat cannot exceed 5.5 knots even if he cranks up to 3500 RPM.  The downside of such efficiency in Carriden is that at dead slow (750 RPM) I am still doing 3.5 to 4 knots coming up the harbour.  I have gotten used to slipping her out of gear in order to limit my speed and the screams from other harbour residents.

So, don't hesitate to have faith in a Martec, although you might want to consider the geared version.Marcus from Carriden
Mk III, Hull #847

---

Marcus Opitz,
Formerly from Carriden, Mk III, Hull #847,
now skippering "Everdina," a 1975 Ontario 32

Hugh Morrin

Member

Re: Yanmar 2 GM Prop Question

Mike,

The Martec prop provides adequate thrust for backing out of a slip, but a folding prop will not generate the same kind of thrust that a fixed pitch propeller will. You need to be a little more cautious coming into your slip, and don't expect to stop on a dime. But other than that, the performance is fine. It is the most common type of prop amongst our racing fleet.

We certainly don't get the performance that Marcus claims, but nor would I expect such performance.

Regards,

Hugh
Hugh Morrin
Blue Zulu
C&C 27 Mk III, #894
Nepean Sailing Club
www.nsc.ca/cc27
</a>

---

Hugh Morrin
Blue Zulu, C&C 27 Mk III, #894
Nepean Sailing Club, www.nsc.ca/cc27
President and back-up webmaster, C&C 27 Association

pura vida

Member

Re: Yanmar 2 GM Prop Question

Thanks guys, I used to race on a J29 and most of the time we just pushed the boat out of the slip. Since I sail Wind Horse alone I have to depend on my Yanmar more than I would like. I generally cut the engine a long way from the dock and drift in. It is always a soft landing (jinx). I'm in a big powerboat slip and in the summer can sail out on the south wind, but in the winter months the north wind can pin me to the dock and that is my main concern.

I'll see what happens. The marina has offered to call the diver for me. Since they control his access to around 1000 boats, they may have more pull than I. Right now travellift time is very expensive due to the hurricane work. With the amount of salvage going on, I may just pick up a used prop and pay a diver to install it. The sad part is that we are in the middle of our sailing season.
Mike M
SV Wind Horse
#375
Galveston, Tx

---

Mike M
SV Wind Horse
#375
Galveston, Tx