New Yamaha 70

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David Mellon
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New Yamaha 70

Post by David Mellon »

Alas, after 9 years my Evinrude 60 tossed a ring and must be retired. I figure rebuilding a 9 year old engine is a bad investment. Yamaha has a new 70 horse engine and is providing a nice discount to promote it. Seems like the right fit for my 26M. Unlike the Evinrude this engine will require 8 hours of break-in time. I will get to know the greater Long Beach/Los Angeles harbor very well by the time I am done with that. Does anyone else run this new engine?
SENCMac26x
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Re: New Yamaha 70

Post by SENCMac26x »

I got mine last year and love it!

Top speed was 25mph @ wot(6200rpm) with me alone and ballast out.

Ballast in with family @18mph, 20-21 with ballast out

This past Sunday, Cruising 2 adults, 2 kids ballast out about 4000 rpms (11-13mpg) burned @4 mpg

In previous trips I was able to make it ~32 miles (Carolina Beach to Baldhead Island and back) @3500 rpms on just about 7 gallons of fuel
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mallardjusted
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Re: New Yamaha 70

Post by mallardjusted »

Great outboard. I've had mine a little over a year. For my 26X, seems like the perfect outboard! (for the 8 years previous I had a 50 Suzie).
bahama bound
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Re: New Yamaha 70

Post by bahama bound »

SENCMac26x wrote:I got mine last year and love it!

Top speed was 25mph @ wot(6200rpm) with me alone and ballast out.

Ballast in with family @18mph, 20-21 with ballast out

This past Sunday, Cruising 2 adults, 2 kids ballast out about 4000 rpms (11-13mpg) burned @4 mpg

In previous trips I was able to make it ~32 miles (Carolina Beach to Baldhead Island and back) @3500 rpms on just about 7 gallons of fuel
Can you clarify the fuel consumption ? I was little confused ? Are you saying you were 11-13 mpg ? Or 11 mph ?
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Re: New Yamaha 70

Post by Catigale »

Well, using the rule 1 gallon per hour per 10 HP for a medium size outboard....

At half WOT skipper is developing roughly 30 HP.

Say 12 mph
So 3 gallons per hour and thus 12mph/3gph or 4 mpg.

:D
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Re: New Yamaha 70

Post by bahama bound »

When you google fuel consumption for a single brand that cool tach comes up and it shows you g.p.h for every motor made at the rpm .but for some bizarre reason ,every Yamaha that you choose is 4 stroke with exception on the 70 which it shows as a 2 stroke ???
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Re: New Yamaha 70

Post by SENCMac26x »

bahama bound wrote:
SENCMac26x wrote:I got mine last year and love it!

Top speed was 25mph @ wot(6200rpm) with me alone and ballast out.

Ballast in with family @18mph, 20-21 with ballast out

This past Sunday, Cruising 2 adults, 2 kids ballast out about 4000 rpms (11-13mpg) burned @4 mpg

In previous trips I was able to make it ~32 miles (Carolina Beach to Baldhead Island and back) @3500 rpms on just about 7 gallons of fuel
Can you clarify the fuel consumption ? I was little confused ? Are you saying you were 11-13 mpg ? Or 11 mph ?
Sorry, GPS was varying between 11-13 miles per HOUR not per gallon, I'm pleased with the fuel burn rate, but not THAT pleased! :D
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Seapup
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Re: New Yamaha 70

Post by Seapup »

Its very compact with its curved cowl. The fact that 4 strokes have been around long enough to get the early bugs worked out and its a Yamaha I would have to think its solid, much the same as any current motor. What are they going for mounted and ready to go?
When you google fuel consumption for a single brand that cool tach comes up and it shows you g.p.h for every motor made at the rpm .but for some bizarre reason ,every Yamaha that you choose is 4 stroke with exception on the 70 which it shows as a 2 stroke ???
Its probably just not updated for the newest models.

I think that site is a good start point and accurate for a motor in with a linear load, or for a mac at below hull speed and again at WOT. Actual consumption is not that linear IMO. Midrange plowing with a mac the motor has to drink extra fuel to achieve RPMS with very little increase in speed. Unless you are underpropped with small blade area allowing a ton of extra slip, the prop is going to grip and need extra fuel to maintain RPM.
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[Fraid-Knot]
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Re: New Yamaha 70

Post by [Fraid-Knot] »

I just upgraded my merc 50 to the new Yamaha F70LA. I am very happy with the motor! It weighs about 100lbs less than the 50 and has the extra hp, the perfect o/b for my 26x! I just completed the break in hours. As far as speed, I've only got around about 16kts, but I was loaded to the gills with camping gear and 2 buddys. Fuel consumption was not as bad as I thought. At varying speeds, I only used about 10gal on the 20 mile trip and back. I sailed around 6 of them. The only complaint is I wish I could trim out a little more and get the bow down. I plan on trying a 5 degree wedge. Other than that, I'm happy about the upgrade.
Last edited by [Fraid-Knot] on Mon Aug 31, 2015 10:13 am, edited 1 time in total.
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Re: New Yamaha 70

Post by Wind Chime »

FUEL TYPE?

Does it really matter what type of fuel we use?

The new Yamaha manual says" Recommended Fuel
Regular Unleaded (Minimum Pump Octane 87)"

My 2000 Suzuki DF50 manual says" Suzuki highly recommends the use of alcohol-free unleaded gasoline with a minimum pump octane rating of 87 ((R + M)/2 method) or 91 (Research method)."

I'm no mechanic, so what's the difference to the engine between; 87 & 91? And given a choice which is best?
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Re: New Yamaha 70

Post by Tomfoolery »

Wind Chime wrote:I'm no mechanic, so what's the difference to the engine between; 87 & 91? And given a choice which is best?
Same thing. Different methods of measuring. RON method gives 91-92 octane, MON method gives 82-83 octane, and (R+M)/2 gives 87 octane, all for the same fuel. AFAIK, only the (R+M)/2 method is used in the US and Canada.
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Re: New Yamaha 70

Post by Catigale »

Interesting they recommend ethanol free gas

Other than at airport, you can't get that where I am in upstate NY
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Re: New Yamaha 70

Post by Johnacuda »

Catigale wrote:Interesting they recommend ethanol free gas

Other than at airport, you can't get that where I am in upstate NY
I'm pretty close, and just noticed that Stewarts Shops are now selling Ethanol Free Premium 91 octane at most stores.
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Re: New Yamaha 70

Post by SENCMac26x »

Catigale wrote:Interesting they recommend ethanol free gas

Other than at airport, you can't get that where I am in upstate NY
Luckily here there are several choices for ethanol free gas, but its always premium, so I havent run anything but 93 ethanol free in it.

And to the gentlemen saying they cant throttle in reverse, Ive applied extra power in reverse a time or 2, are you sure?
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Re: New Yamaha 70

Post by Catigale »

Johnacuda wrote:
Catigale wrote:Interesting they recommend ethanol free gas

Other than at airport, you can't get that where I am in upstate NY
I'm pretty close, and just noticed that Stewarts Shops are now selling Ethanol Free Premium 91 octane at most stores.
I'll check that out John. Is that summer only by chance?
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