20 or 30 hp?

hipster dufus

Petty Officer 2nd Class
Joined
Jan 1, 2009
Messages
169
ok i have picked out my retirement boat, 1648 mv weldbilt. now i need to choose an engine. 20 or 30 hp 4 stroke tohatsu. opinions on efi on the 30? i take my boat out about once a week from feb to nov, will ethanol cause issues with an efi? i drain my current carb on my 9.8 after every use.my brain is telling me to get the bigger motor. so,...thanks for any and all advice
 

TOHATSU GURU

Admiral
Joined
Jul 22, 2004
Messages
6,164
Re: 20 or 30 hp?

Big difference between the 20 carbed model and the 30 efi model. No fuel issue with efi. If you have to take the engine on and off the boat go with the 20. Otherwise the 30 will give you a lot more.
 

pvanv

Admiral
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Apr 20, 2008
Messages
6,573
Re: 20 or 30 hp?

Yep. Both good motors, but very big differences. The 30 is much smoother, being a 3-cylinder. If you get the EP (remote), it will start/drive like an EFI automobile. But it is a bunch heavier. With any EFI, if you lay-up for a month or more, drain the fuel (via the drain plug at the vapor separator), just as you would empty the carb daily on the 20.
 

hipster dufus

Petty Officer 2nd Class
Joined
Jan 1, 2009
Messages
169
Re: 20 or 30 hp?

thanks for the info. the 25 hp does not seem to be enough bang for the buck, lots more weght and only 5 more hp. although the 3 cylinder and efi sound appealing. the motor will not be coming off and on.
 

pvanv

Admiral
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Apr 20, 2008
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6,573
Re: 20 or 30 hp?

The 25 is a de-tuned 30. So, as long as the boat will handle it, get the 30.
 

Davem3

Chief Petty Officer
Joined
May 15, 2011
Messages
542
Re: 20 or 30 hp?

in my book better to have and not need it, than the other way around.

Sorry, i am a guy and as such Size matters, if you can afford it get the 30.........

i am not sure if there is any weight difference at all,but if the boat is rated for it , heck ya
 

hipster dufus

Petty Officer 2nd Class
Joined
Jan 1, 2009
Messages
169
Re: 20 or 30 hp?

another stupid question. i am thinking about putting this 30 hp on a 16 in transom, is this gonna work? is it safe?if i can get a 20 in i will go with it but i dont have an ansewr to that yet. thanks
 

Davem3

Chief Petty Officer
Joined
May 15, 2011
Messages
542
Re: 20 or 30 hp?

20 inch gives you more breathing room, getting swamped is never fun, you would be surprised what a difference 5 inches can make .................
 

pvanv

Admiral
Joined
Apr 20, 2008
Messages
6,573
Re: 20 or 30 hp?

A long shaft will add drag. You will have less top speed, and trim will be more critical... but it will indeed work. The Jap motors are about 1-3/4" longer than the "nominal" length, so a Tohatsu short is actually intended for a 16-inch transom. See http://www.tohatsu.com/tech_info/faqs.html#Q17
 
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hipster dufus

Petty Officer 2nd Class
Joined
Jan 1, 2009
Messages
169
Re: 20 or 30 hp?

ok one more question. can u retune a 25 up to a 30? i fish a 25 hp restricted lake and thought i could just uptune a 25 to a 30.
 

just_crsn

Seaman Apprentice
Joined
Feb 29, 2008
Messages
49
Re: 20 or 30 hp?

ok one more question. can u retune a 25 up to a 30? i fish a 25 hp restricted lake and thought i could just uptune a 25 to a 30.

No they cant be retuned....only switching the ecm.....which is $1000.
I have a Mercury 25hp efi on a 16ft rivited flat bottom jon boat and it works great. It is a rebadged Tohatsu.
 
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