outboard motor shaft length e27
Jeff Asbury
Principal Partner
The longer, the better!
IMHO, The longer, the better, go with the 25". You don't want to be sucking a lot of air if the seas get big when your trying to motor.
IMHO, The longer, the better, go with the 25". You don't want to be sucking a lot of air if the seas get big when your trying to motor.
I'd recommend measuring from the mount surface to the waterline for your peace-of-mind. Shaft length is the distance from the top of the "C" clamp(mounting surface) to the cavitation plate(horizontal fin above the prop) and as long as the cav. plate is well submerged you're good to go.
chuckd
Member I
I guess I'll measure the one I have
My concern with getting one that is too long is that the prop will drag when the motor is in the up position. Since there is no movable mount, the motor just pivots up. I'm worried that a 25" shaft may drag. A little drag going downwind is no big deal, but I'd like to keep it to a minimum.
Thanks again
Chuck
My concern with getting one that is too long is that the prop will drag when the motor is in the up position. Since there is no movable mount, the motor just pivots up. I'm worried that a 25" shaft may drag. A little drag going downwind is no big deal, but I'd like to keep it to a minimum.
Thanks again
Chuck
How to eliminate prop drag from a long shaft motor.
Chuck, Email me back channel at glynjudsonatroadrunnerdotcom and supply me with a fax or postal address. I'll send you a fix for that potential problem in the form of a short, one page article and photos that I had published in Good Old Boat Magazine on just that subject. It's actually a device I fabricated that assists in raising the engine utilizing the split aft stays but also serves to elevate the engine in a race or other situation enough to get the prop out of the water. As a matter of fact, the photos illustrate its use on an E27. Glyn Judson, E31 hull #55, Marina del Rey, CA
Chuck, Email me back channel at glynjudsonatroadrunnerdotcom and supply me with a fax or postal address. I'll send you a fix for that potential problem in the form of a short, one page article and photos that I had published in Good Old Boat Magazine on just that subject. It's actually a device I fabricated that assists in raising the engine utilizing the split aft stays but also serves to elevate the engine in a race or other situation enough to get the prop out of the water. As a matter of fact, the photos illustrate its use on an E27. Glyn Judson, E31 hull #55, Marina del Rey, CA
Chuck, Didn't know it was a replacement. If your happy with your current motor(past tense) just replace it in-kind. Check out www.edsmarinesuperstore.com for some price comparisons. Yamaha high-thrust would be a perfect adaptation. They're used primarily as kickers for fishing boats but the high-thrust is applicable to any displacement hull.
**Glyn**, Would it be possible to post a "link" here? For future use. Curious about your "lifter".
OOPS!
**Glyn**, Would it be possible to post a "link" here? For future use. Curious about your "lifter".
OOPS!
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Steve, I believe that your link question is really for Glyn...
I do have a comment about the Yamaha OB. We put a Yamaha "Hi Thrust" 4-stroke 10 hp on our prior 26 foot sloop. It burned only a half gallon per hour at 6 kts. and was quiet. Large 11 3/4 " three blade prop and only came in a 25" leg model. Three (!) to one reduction gear.
Years later, our YC has replaced both old 60 hp two-stroke OB's with new Yamaha 25 hp Hi Thrust 4-stroke engines and we are VERY pleased with the result on both of the work boats.
This little portion of the Yamaha engine line up is aimed at displacement speed hulls, and fully lives up to the promises, IMHO.
As to what shaft length is "right" this will always be a compromise. Our engine would indeed drag the prop a little when we got over 8 kts on a reach or run, and start spinning the prop... At that speed, this was not an inconvenience. Like the E-27, we had a fixed mount via a cutout in the transom.
Note that there will (!) be times when you have to motor into a short chop in a narrow channel and will want all the prop depth you can get!
"Choices and Options" as someone once said....
Loren
I do have a comment about the Yamaha OB. We put a Yamaha "Hi Thrust" 4-stroke 10 hp on our prior 26 foot sloop. It burned only a half gallon per hour at 6 kts. and was quiet. Large 11 3/4 " three blade prop and only came in a 25" leg model. Three (!) to one reduction gear.
Years later, our YC has replaced both old 60 hp two-stroke OB's with new Yamaha 25 hp Hi Thrust 4-stroke engines and we are VERY pleased with the result on both of the work boats.
This little portion of the Yamaha engine line up is aimed at displacement speed hulls, and fully lives up to the promises, IMHO.
As to what shaft length is "right" this will always be a compromise. Our engine would indeed drag the prop a little when we got over 8 kts on a reach or run, and start spinning the prop... At that speed, this was not an inconvenience. Like the E-27, we had a fixed mount via a cutout in the transom.
Note that there will (!) be times when you have to motor into a short chop in a narrow channel and will want all the prop depth you can get!
"Choices and Options" as someone once said....
Loren
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Brand and type outboard.
Loren, We had the identical Yamaha on our E25+. It was that boat and engine combination that I made the engine lifter for. You see, Marilyn could do virtually everything on the boat by herself but raise that rather heavy engine. My device made that a walk in the park for her and my friend Lloyd used it on his boat for that and to raise the engine even farther so prevent exactly what you just described. Glyn
Loren, We had the identical Yamaha on our E25+. It was that boat and engine combination that I made the engine lifter for. You see, Marilyn could do virtually everything on the boat by herself but raise that rather heavy engine. My device made that a walk in the park for her and my friend Lloyd used it on his boat for that and to raise the engine even farther so prevent exactly what you just described. Glyn
Chuck,
I have a '73 E27 with the standard transom cutout. I recently bought a Tohatsu 9.8 four stroke with a 25" shaft. It works fine and does not drag except when sailing downwind at 7+ knots tends to wet the prop now and then. The previously motor was an 8hp, 2 stroke long shaft Evenrude. I think 20' shaft. That motor popped out of the water every time I went forward to bring down the head sail. Not a problem now except that if you like steering with the outboard you probably won't be able to with a four stroke. The motors are too large for the cutout so you'll have to steer with the tiller. A real pain when reversing. While I have no afilliation with the vendor, I bought the motor online. No tax or shipping. Big box shows up, put the oil in and follow the instructions for break-in. I got the electric start version so it charges my battery. Definetly one of the better impovement to my boat last year. It's quiet, i don't have to mix out, and the smell is better.
Good luck!
Grant Kiba
'73 E27, Antioch, CA
I have a '73 E27 with the standard transom cutout. I recently bought a Tohatsu 9.8 four stroke with a 25" shaft. It works fine and does not drag except when sailing downwind at 7+ knots tends to wet the prop now and then. The previously motor was an 8hp, 2 stroke long shaft Evenrude. I think 20' shaft. That motor popped out of the water every time I went forward to bring down the head sail. Not a problem now except that if you like steering with the outboard you probably won't be able to with a four stroke. The motors are too large for the cutout so you'll have to steer with the tiller. A real pain when reversing. While I have no afilliation with the vendor, I bought the motor online. No tax or shipping. Big box shows up, put the oil in and follow the instructions for break-in. I got the electric start version so it charges my battery. Definetly one of the better impovement to my boat last year. It's quiet, i don't have to mix out, and the smell is better.
Good luck!
Grant Kiba
'73 E27, Antioch, CA