Evinrude eTEC 35.2ci - 15ho, 25, 30hp - kicker?

[KC8QVO]

I had this posted in the Evinrude forum but that may not be the right place. It isn't a repair oriented question.

It appears all of the following eTEC motors are the same motor based on the cubic inches and weight:

15 high output (2 stroke eTEC, not the 4 stroke portable, non-HO version)
25hp
30hp

Aside from the obvious hp increase, is there anything really different about them?

I've been thinking about getting a boat and how I want to set it up for a while - still studying the options. I am pretty well set on an eTEC 115 main, but there aren't any small hp matching motors really suitable as a remote "kicker" like the Merc 9.9 pro kicker or bigfoot. The "smallest" evinrude appears to be the 15ho. Though, with the size of the motor and a 25/30 being the same frame/displacement, from a size perspective I'd rather get the bigger hp. I could pull it off and run it as a main with a skiff just as well.

I have heard with some motors it is not good to run them long at low speeds because of carbon build-up, etc. This is one of the main benefits of a kicker when trolling or otherwise running at slow speeds - you can run the kicker harder at that speed than a main. I am looking at the kicker as a two part objective - primarily back up power if I loose the main (rip off the lower unit, mechanical failure, what have you), as well as a better option for trolling.

From a back up power perspective - I don't know that I would gain much push (translate that to speed), realistically speaking, at 30hp than 15 because of the size/weight of the boat. That power may not even get the boat to plow, let alone have any chance of getting on plane (alum 16'6", 88" beam, 13deg deadrise, under 1100lb dry hull weight).

What about from an engine tuning perspective? eTEC's are injected engines. So is it really the tuning alone that affects the hp? On carbed engines the higher hp models in a line up mostly just had bigger carbs. If it is only tuning then running a higher hp motor slow would be the same as running a lower hp at the same speed, in terms of fuel delivery, carbon build up, etc, no? If the motor is dual purpose for a kicker and skiff power the higher hp makes more sense.

Any thoughts on my logic here? Any thoughts on the wear/use of the motors?

 

[ondarvr]

Those E TECS are very good motors, but you don't need anything bigger than a 9.9, and the E TECs are heavy for a small boat. On these motors it wouldn't make much of a difference on trolling between the two different HP ratings, on carbed motors it can, the smaller carb can help the motor run much better at low RPMs. And there are frequently many differences other than the carb to create the extra power.

I personally don't care if the motors match, I just want the best motor for the application, some people really stress over it though, so it's personal choice on that part of it.

The Yamaha T9.9 is currently the the best small motor for trolling purposes.

 

[jbcurt00]

Its a holiday weekend. Shouldnt be surprising that there is reduced traffic and it might take a couple days to get a reply to such a specific opinion question.

Try not to start multiple topics in multiple forums about the same subject. If you think you started a topic in the wrong forum, just ask any Mod to move it for you.

I closed the other topic.

Better get busy, the best time to get a boat deal generally ends w the start of the bulk of fishing and boating season in most areas.

 

[jimmbo]

As for your question regarding more than one HP rating from same displacement

Bigger carb/throttle body is part of it, Port timings and port size in another part of it, higher compression in some cases, Exhaust tuning is the final part of it. More air-fuel in means more exhaust to get rid of. If you have two or three engines, same displacement different HP, the lower HP models have better low end power and often will plane a boat quicker than the higher HP model. However as the revs climb the higher HP will pull ahead and have a higher top speed.

 

[JimS123]

My 9.9 is used as a kicker for trolling, hours and hours at a time. I have hotter spark plugs, plus she runs a low pitch "sailboat prop", thus she runs at relatively high rpms. I have NO plug fouling. When I switch the motor over to my "skiff", I put a "regular" prop back on and she works well there too.

What you need for a kicker is an 8 HP, or certainly no larger than a 9.9. If you put that big eTEC on your aluminum boat, whether its a 15 or a 30, you will list, the transom will be deep in the water and you won't be happy with the performance.

A kicker for a 16.6 tinny should ideally be a 2-stroke. Too bad they don't make them any more.