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CHICKFISHING58
07-20-2005, 10:13 PM
Whatís the difference between the Diameter & Pitch of a propeller I' trying to understand this manual I want to replace the one I have now when I fix the lower unit not for sure of Whatís best for mine its a tohatsu 18hp 2 stroke
I figured I would put it on the board since I have been bugging SE(Steve) with PM's finally after the 6th or so he politely told me to read the manual :o(JK) ;)
Whatís the diffrence between 3 blade and 4 they also ask for the year of motor thanks to Steve I found the model and serial number but what about the year of the motor where would I fine it

SturgeonVirgin
07-21-2005, 05:13 AM
Whatís the difference between the Diameter & Pitch of a propeller I' trying to understand this manual I want to replace the one I have now when I fix the lower unit not for sure of Whatís best for mine its a tohatsu 18hp 2 stroke
I figured I would put it on the board since I have been bugging SE(Steve) with PM's finally after the 6th or so he politely told me to read the manual :o(JK) ;)
Whatís the diffrence between 3 blade and 4 they also ask for the year of motor thanks to Steve I found the model and serial number but what about the year of the motor where would I fine it

Lesse, if can do this without screwing up; diameter is how big a round the prop is; pitch is the angle of the blade, basically how much of a bite it will take as it makes one full turn, usually both are expressed in inches.


Most of the time the size of the prop is stamped on the body of the prop somewhere. On a lot of motors the serial num,ber wil tell you the year and model of the engine not sure baout tohatsu though.

3 blade versus 4 blade, most times the three is what you find out there, the 4 is used for heavy load or kicker motor type situations. Unless you know you need more or less prop, stay stock, its easier to keep track of that way.

somebody
07-21-2005, 06:26 AM
ifyou talk to sierra prop on mill street in reno he will help you. if you need help replacing seals let me know, its really very simple

SuperDave
07-21-2005, 06:43 AM
Chick, with an 18 HP OB, you won't realize any benefit from changing your prop. Not enough power to convert. Best to just have another one as a back up.

drstressor
07-21-2005, 08:09 AM
Chick's prop is a little "customized" from "bottom abrasion". It would make a good spare.

Chick, look for the diameter and pitch of your prop stamped on the base. It will say something like 11 X 17, which is the diameter and the pitch. You have to remove the prop to see this.

The other info the guys gave you is right on. You don't need a 4-blade and you should get the same size prop that already have. Sierra prop can tell you the size prop you have/need just by looking at yours if the stamped information can no longer be read.

BTW, make sure that whoever replaces your prop seal inspects the area where the shaft goes into the propeller mount. If a downrigger wire got caught in there, there could be a lot more damage than can be repaired by just replacing the seal. Trust me, I've been there. :( But I didn't see any evidence for this when I pulled your prop.

kstone44
07-21-2005, 07:47 PM
Chick check out this site , you can see the different sizes availiblehttp://www.boat-props.com/propellers/s/Tohatsu/Outboard/

blue_chrush
07-22-2005, 11:48 PM
just go here and get the 411.....
then you'll know

http://www.props.net/propsnet1.html#pitch

CHICKFISHING58
07-23-2005, 12:57 PM
Thanks great info didnít realize how much there is to learn I guess its never to late to teach an old dog tricks ;D ;)