Tohatsu 3.5 B2 propeller

[Sea Rider]

Hola Elvin

Just a technical advise:

What is the standard number code propeller factory delivered on a Tohatsu 2 strokes 3.5 B2 long shaft engine. Is it a plastic 6 or 7 prop code. Need to push a J-24 sailboat that weights 1.5 tons. Was checking the owners manual fot this model, found this info:

Propeller model G-6 & H-6 both alum props (3 x 188 x 145)

Seems there is a erroneous posted information, what is the difference between a G & H model props ? one is plastic, other aluminum, if so, which is which ?

Happy Boating

 

[pvanv]

Re: Tohatsu 3.5 B2 propeller

Not to upstage TG, but we do a lot of these old beaters.

The standard 3-blade plastic prop is a 7 pitch, 3F0-64101-0
Optional 3-blade 6-pitch Aluminum prop is 3F0-64102-0
Optional 3-blade 6 pitch plastic prop is 309-64106-0

We are now using stainless shear pins in all applications, as sometimes people would shear the brass ones if they were evern slightly above idle when shifting into gear.

Our customers use these on J-22's a lot. If racing a J-24, it would be OK, especially with the 7-pitch prop, because it's such a lightweight motor, but it will be a little low on horsepower for that sailboat. So if a cruising auxiliary, I would go with a bigger hp motor if it's available.

 

[TOHATSU GURU]

Re: Tohatsu 3.5 B2 propeller

The 7 pitch was standard for the U.S. years ago. It may have changed now. That engine is not on the import list now so I would look at the factory website for the most current data. We never used the letter designations on that size propeller and Paul has given you the actual part numbers...Part numbers are always used rather than letter codes for accuracy. Also, never depend on part data information in the owner's manuals. Just use that factory website.

 

[Sea Rider]

Re: Tohatsu 3.5 B2 propeller

Hello Paul and Elvis

Thanks for the tech information

Last tech prop issue:

The idea of not using a larger engine is because this 3.5 fits nicely under the bed lid, the 5 won't fit nicely. It will be used as a auxiliary in case of very poor wind. With complete crew will be nearly 1.8 tons, would you recommend to go for a 6" pitch wether plastic or aluminum for a better weight displacement compared to factory standard 7" pitch ? Speed is not needed, better push is. What are your ideas.

Happy Boating

 

[TOHATSU GURU]

Re: Tohatsu 3.5 B2 propeller

I would use a 369641070 aluminum 5.7 pitch. It wouldn't help though...Your so under hp'd nothing is going to make a difference. You need a larger frame style engine. In the Tohatsu series a 4, 5 or 6 with the emphasis on the 6.

And Elvis has left the building

 

[pvanv]

Re: Tohatsu 3.5 B2 propeller

I agree 100% with Elvin.

Lower pitch for better low end. There isn't any "trick" High Thrust "elephant ear" prop for that model (but there is for the 4/5/6), so the best for the 3.5 will probably be the 5.7 pitch aluminum prop that Elvin mentioned. And do run the stainless shear pin.

Your J-24 is a bunch heavier than the J-22's that run our 3.5 2-strokes, and they are strictly racing, so it's just to get to/from the dock. They prefer the 3.5 2-stroke because of its extreme light weight. Yet they are definitely low on power.

Better yet, if you can fit the cowling into the boat, go with a 6 hp, and run the EE prop. For sail and other heavy applications, we sell more of those EE props by far than the standard props. Brilliant thrust.