The best fuel economy - outboard on V

[bgreene]

150 HP on V20/21 really seems the perfect choice in terms of total performance .....weight/fuel economy / usability .....

These newer 4 strokes being the best of all.

Really enjoy the big Etec 200 HO on my V21, its more than enough motor.
That said - if V21 max rating was 225, I would have ......:)

[pjbrownva]

Originally Posted by randlemanboater

I had a Johnson (Suzuki) 140 on my V20, cruising in the mid 20's I consistently got 5 statue mpg.

Top speed was 39-40 depending on load.

Mine was a 2003...I would think that technology has progressed in the last 17 years where higher hp motors should be able to match that economy.

Interestingly, my Ranger 250C weighs twice the weight of the V20 and has double the horepower (close anyway).

I get the same top speed but the mpg is exactly half.

I have that exact same motor (Johnson 2003 140 4 stroke) on my V20, and it's awesome. I get about 4 MPG with it... I'm getting some electronics to measure the fuel burn more accurately, but I guess if I kept a log of miles and refuels I wouldn't need the fancy stuff.

Working in my prop. Currently have a 13.5 17" pitch with a lot of rake... looking to go with at 15" pitch with less rake so that the stern comes up more... right now I need to use too much trim on the trim tabs to keep the bow nice and low so that she cuts through the waves.

Once I have it dialed in, I wouldn't be surprised if I see 5 mpg too.

Currently top out at about 30 MPH, but the bottom needs sanding and painting, and I'm over-propped, so I know she'll do more.

The Suzuki's are known for being great on fuel. Can't comment on the Merc 4-strokes, as I don't have any experience.

Also, check the weight of the Suzuki 140... at 410 lbs, she's really light which also helps with fuel burn.

Edit: Just looked up the Merc 4 stroke 150... it's 455 lbs... so about the same pwr to weight ratio as my Zuki.... and it seems like a nice motor too.

[bgreene]

Let us know after you change prop ..... thinking your top speed should go up too

[pjbrownva]

Originally Posted by bgreene

Let us know after you change prop ..... thinking your top speed should go up too

Added a doel-fin on Sunday, and much to my surprise WOW!

I gained 6 MPH on the top end, the engine now hits 35 MPH at WOT with the motor at close to full-down and with the trim tabs all the way up, and she now hits 6200 RPM with that setup (as opposed to about 5400 without the fin).


I get more stern lift, so she rides better and faster with the trim tabs all the way up.

Best speed I got was 35 MPH (GPS)... (50 Gallons of gas... and just me on the boat) with the motor close to full down and no trim tabs... and she now she sings at about 6200 RPM like that. As I trim the motor higher, RPMs increase, but not necessarily speed (I think I get more slip)... when I'm at or near maximum motor trim up, I can hear the prop slipping more and I can the rev limiter.

I'm happy with this 14 x 17 pitch 3 blade suzuki SS prop, and plan to keep it now that I added the doel fin.

The bottom of my boat is rough.... there are some painted over barnacles on the bottom, that I've been slowly scraping off. Because I trailer exclusively, my ultimate plan is to sand and scrape the bottom and refinish with either a gel-coat layer, or a good, smooth long lasting finish (NOT anti-fouling paint,.. since I trailer exclusively).

I expect once I get a smooth bottom and way 'er up, that I'll see even better performance. :-)

[bgreene]

Also look at motor mount height - most riggers lower than needed .

[randlemanboater]

The props I ran were aluminum Suzuki props.

They are sitting on a shelf at my buddies place, he is running a 14x23 on his bass boat, I am sure he would let one or both go if anyone is interested.