30 etec - 16 ft aluminum

[aae0130]

Hi
New around here…….Found this forum while looking up props.

Details
Etec 30 with BRP 10.3 x 12 aluminum 3 blade.
Duranautic aluminum 16 ft side console 20 inch transom
Trolling motor and light 12v lithium in the bow. (TM battery is just 16 lbs)
Starting battery and 6 gallons of gas in stern.
Motor is up high to keep the ventilation plate at or above the surface.
Total weight on the water without people is 950 lbs)

Current WOT with typical load (just me) is 5900 rpm’s at 27/28 mph

WOT with typical heavy load (one passenger) 5800 rpm’s at 25/26 mph

Boat has zero issues planing. Just gets up. No excessive bow rise or struggling.

used primarily in tidal rivers and bays……..

RPM’s verified with tach and double checked using Evinrude diagnostic tool.
Speed is gps on Helix fish Finder……….and iPhone ap.


Operating manual states 5500 to 6000 rpm’s range. Full HP is at 5500 (I think rev limiter is 6250???)

Purchased new in late summer 2016.
I recently read some posts on an etec owners site that Evinrude was recommending staying below 5850 rpm’s as when you exceed that it injects more oil and causes more carbon build up.
I think they had issues with outboards dying young.
I guess I should decrease my rpm’s by about 100 but I do not want to lose any top end in the process.

I am looking for some Solas vs BRP guidance.

I checked the prop finder and it had recommendations that I am now going to ask about.

I think I may want the Amita-3. 10.3 dia. x 13 which puts me up an inch in pitch. I am looking for some opinions on about how much this will drop my rpm. I have read that 1 inch of rpm is about 150 to 200 rpm’s. However this is a different prop design from my BRP.

The “New Saturn“ has a 10.1 x 13 in stainless. I have read that this prop although made of stainless is a fast turner because of thin blades and no cupping (???) Some have stated that switching to this prop from aluminum and same size gave higher rpm’s…..???
This….if true……interests me.

Sorry for the phone book sized post…….wanted to make sure I give the whole picture not to waste anyones time.

I am open to suggestions/wisdom/experiences……..

 

[Scott Danforth]

Just back off the throttle a bit when going solo. You are propped correctly

 

[aae0130]

Just back off the throttle a bit when going solo. You are propped correctly

That’s kinda what I thought…..except some tech/mechanics showed me an Evinrude/BRP write up that shows you should prop for under 5850. So I figured I would try going up 1 pitch but I hate the thought of losing 200 rpm’s.

 

[Scott Danforth]

A cupped prop will drop RPM by 100. Talk to your prop shop

 

[jimmbo]

Hi
New around here…….Found this forum while looking up props.

Details
Etec 30 with BRP 10.3 x 12 aluminum 3 blade.
Duranautic aluminum 16 ft side console 20 inch transom
Trolling motor and light 12v lithium in the bow. (TM battery is just 16 lbs)
Starting battery and 6 gallons of gas in stern.
Motor is up high to keep the ventilation plate at or above the surface.
Total weight on the water without people is 950 lbs)

Current WOT with typical load (just me) is 5900 rpm’s at 27/28 mph

WOT with typical heavy load (one passenger) 5800 rpm’s at 25/26 mph

Boat has zero issues planing. Just gets up. No excessive bow rise or struggling.

used primarily in tidal rivers and bays……..

RPM’s verified with tach and double checked using Evinrude diagnostic tool.
Speed is gps on Helix fish Finder……….and iPhone ap.


Operating manual states 5500 to 6000 rpm’s range. Full HP is at 5500 (I think rev limiter is 6250???)

Purchased new in late summer 2016.
I recently read some posts on an etec owners site that Evinrude was recommending staying below 5850 rpm’s as when you exceed that it injects more oil and causes more carbon build up.
I think they had issues with outboards dying young.
I guess I should decrease my rpm’s by about 100 but I do not want to lose any top end in the process.

I am looking for some Solas vs BRP guidance.

I checked the prop finder and it had recommendations that I am now going to ask about.

I think I may want the Amita-3. 10.3 dia. x 13 which puts me up an inch in pitch. I am looking for some opinions on about how much this will drop my rpm. I have read that 1 inch of rpm is about 150 to 200 rpm’s. However this is a different prop design from my BRP.

The “New Saturn“ has a 10.1 x 13 in stainless. I have read that this prop although made of stainless is a fast turner because of thin blades and no cupping (???) Some have stated that switching to this prop from aluminum and same size gave higher rpm’s…..???
This….if true……interests me.

Sorry for the phone book sized post…….wanted to make sure I give the whole picture not to waste anyones time.

I am open to suggestions/wisdom/experiences……..

The FICHT Engines(the Problem Children), which were the Grandparents of the e-tec, rarely had any issues when run at WOT.
Use of BRP XD50 or XD100, especially the XD100 are designed with DI Engines in mind, and have copious amounts of Detergents in them. I have not seen any Service Bulletin regarding propping for below 5850rpm. Your numbers indicate 50rpm +/- of that, you are not exceeding the 6000rpm, so you should be fine

 

[aae0130]

My prop has some chew spots on the edges so I was going to replace it anyway………..In looking up props I found that 5850 rpm……

I think you guys are right and in my own observation the outboard sounds right and performs well. Planes without issuse….With the thought of no more little 2 strokes being produced I may have become a little obsessed……Lol…….

So now I am going to switch gears and get a 12 pitch to replace my existing prop…..So now the question is do I go BRP or Solas Amita 3?

The Solas is half the cost………but I know the numbers I will get with the BRP. Suggestions?

 

[jimmbo]

2, 3, 4, even 5 Props with the same Dia and Pitch can, and often deliver as many different Results as there are Props. Reasonably accurate Predictions of results are only possible when the Brand and Model of a Replacement Prop is the Same as the one being replaced. Change the Brand or the Model, and YMMV
Myself, I like Mercury Props, I run one on my VP. For about 3/4 Century, Mercury has been at the Leading Edge of Prop Design. OMC, now BRP, finally got into Decent Prop Engineering in the very late 60s, at least on engines 55 and up. Over the next couple of Decades the Engineering trickled down to the 20hp+ engines.
I would pick a BRP Prop over a Solas, or Turning Point, in a Heartbeat