Tohatsu Outboard (alternator)

[solodare]

I'm currently looking to buy a new Tohatsu, I was looking at the 4hp model when I noticed the "alternator" option. (for the price of the install of said alternator on the 4hp you can get the 6hp Sail pro for the same price pre installed with the alternator)

I assume the Alternator is for charging a battery bank, if so does it need to be wired through something else or just straight to the battery? I don't know any thing about battery banks either.
I guess my main question is it worth the extra money?

Also is 20" the right size for the Venture 22? 

[Ulladh]

I have a 6hp Tohatsu with an alternator, bought before the SailPro was on the market. My alternator like the SailPro produces about 5amp maximum, but I would assume since the motor is rarely run at max rpm I am probably getting not much more than 2 amp.

This is enough to maintain a battery but not to significantly increase the battery charge unless you do a lot of motoring with minimal demand for electric from devices. I also have a small solar panel producing about 0.5 amps for maybe 3-4 hours a day, this is enough for my electric demand on a 20ft sailboat when not on shore power.

Running a tiller pilot may consume as much as the alternator can produce.

I would suggest unless you get more specific advise on shaft length, go with the ultra-long 25"

The Tohatsu is a very reliable motor though be prepared for the vibration and noise which is normal for a single cylinder engine. 

[solodare]

Thanks for the tip Ulladh,
Like a said, I was just going to get the 4hp. since there is not a lot of charging power and I doubt I would use the motor a lot, I think I'm leaning more torward the 4hp. or even the 3.5

Anyone with a 22 mac or ven please let me know what shaft size to get.
I have the drop down engine mount. I don't know if that is standard for macs?

[Tim]

the safest thing to do would be measure the bracket to your waterline, older boats sometimes change mounts so one will not be the same as another.

[Norman]

Standard shaft too short, long just right on mine.  I have the drop down mount too.

Charging is nice, 4 hp is adequate, but at the same cost, it is a toss up. The smaller motor is easier to mount or remove, probably not an issue for you, and it will get a little better gas mileage.  Since charge rate goes up rapidly with rpm,the 4 will tend to give you more charge at the same speed.

On the other hand, factory installed equipment is much more likely to be trouble free.

Either motor would make me happy on my Mac 22.

The charging wires direct to the battery, the motor will have a fuse, and the rectifiers block current flow back to the charge coil.

Norman

[Lars]

I just got my new 4 hp longshaft  2015 model this week . This is my third tohatsu since 2010  . The 4, 5, and 6 horse are all the same engine. I have had one each, however the new 4 is noticeably bigger than the older engines due to the internal tank .the shifter in the front  is a great improvement and it seems  to have less vibration . I have about 3 hours in the break in . also it seem to weigh a lot more than the 2012 6 hp I am used to but I have not weighed the thing. the difference in the performance is due to different props on the engines nothing else.