MerCruiser 140 Fuel Economy

[Jacalore]

Trying to get a handle on fuel consumption for my '85 MCM 140. What can you tell me, cruising, WOT? Any info appreciated, anything I can compare to what I will experience with new (to me) '85 MerCruiser 140. Thanks.

 

[achris]

Re: MerCruiser 140 Fuel Economy

Budget for about 20 litres per hour at cruising speed (say about 3000rpm)...

Boats use WAY more fuel than cars. Simple reason, they are ALWAYS under load. Unlike a car, where you back the throttle right off once you reach cruising speed, boat engines are working very hard all the time...

HTH,

Chris.......

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

Thanks, Chris. 20 litres per hour... hmmm... I need a conversion table.

 

[thumpar]

Re: MerCruiser 140 Fuel Economy

I had a 1983 120. The lake we run is 25 miles long and we would normally go to the end and back at around 2800-3500 rpm stopping a few times along the way. $35 would usually fill it back up unless I was a little hard on the handle. I would think the 140 is pretty close to that maybe just marginally more.

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

20 liters = 5.28344 gals... so, about $20/hr?

 

[achris]

Re: MerCruiser 140 Fuel Economy

20 liters = 5.28344 gals... so, about $20/hr?

I have no idea what fuel prices are where you are... Where I live, that would be more in the line of $30/hr. If you live in the UK, try about $50/hr....

(BTW, where I live, 20 litres is 4.4 gallons )

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

This is getting confusing, you'd think the world could agree on a standard of measurement!

 

[achris]

Re: MerCruiser 140 Fuel Economy

This is getting confusing, you'd think the world could agree on a standard of measurement!

There is, it's called the litre....

BTW, the US came up with its own version of the gallon, for... tax purposes... :facepalm:

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

liters, quarts, imperial gallons, us gallons... can't we all just get along?

 

[achris]

Re: MerCruiser 140 Fuel Economy

liters, quarts, imperial gallons, us gallons... can't we all just get along?

:laugh:

 

[JimS123]

Re: MerCruiser 140 Fuel Economy

Here are some real stats for a 1984 3.0 liter MCM140...a typical sunday:

2 hours at ~1500 rpm, 6 mph - 12 miles
1 hour at ~3000 rpm, 30 mph - 30 miles

42 mile trip - 6 gal, or ~7 mpg.

If I skip the 6 mile no wake canal and launch right in the river, and run at the 3000 rpm for 2 hours instead, the gas consumption is no more than ~7-8 gal.

20 L = 5.28 gal.

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

Thanks, that's informative!
So, on average, a tank of gas (21 gal) is good for a weekend.

 

[achris]

Re: MerCruiser 140 Fuel Economy

Thanks, that's informative!
So, on average, a tank of gas (21 gal) is good for a weekend.

nope... That's a GREAT weekend!!!

 

[fishrdan]

Re: MerCruiser 140 Fuel Economy

So, on average, a tank of gas (21 gal) is good for a weekend.

Maybe... Depends on how much you use the boat and if this is a short 2 day weekend or a long 3 dayer. I was out last Saturday, ran for 15-20 miles at 3500RPM, then tubing for 3-4 hours. I topped off the 27 gallon (US gallons, not imperial gallons, liters or anything goofy like that ) tank before heading out and it was at 3/4 when we got off the lake.

THOUGH,,,,,, boat fual gauges are notoriously inaccurate and I'd have to fill it again to see exactly how much fuel we really used.

The boat averages around 4-5 MPG cruising and I went out on 3-4 trips last year on a tank of fuel.

 

[achris]

Re: MerCruiser 140 Fuel Economy

Ok... Since we're referencing trips... My last trip was out fishing... Went out Sunday afternoon, got home Monday morning. Did about 53 nautical miles (61 statute miles, 98 kilometers) and used about 75 litres of fuel (16.5 gallons, 20 US gallons, 15,216 teaspoons).... That was mostly cruising at around 2800 to 3500 rpm....

Oh, got this for my troubles..

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

Blimey!
Nice fish, what is it, some sort of grouper (or bass)?

I would think my MCR 3.0 would be a bit more frugal on petrol consumption than your 4.3, no?

 

[500dollar744ti]

Re: MerCruiser 140 Fuel Economy

You are going to get about 5mpg if you cruise at an efficient speed and your engine is in good tune.

 

[achris]

Re: MerCruiser 140 Fuel Economy

Blimey!
Nice fish, what is it, some sort of grouper (or bass)?

Glaucosoma hebraicum, West Australian Dhufish. Of the sea perch family...

More info on this fish.

I would think my MCR 3.0 would be a bit more frugal on petrol consumption than your 4.3, no?

Hull shape and material also has a huge bearing on fuel economy. As an example, my brother has a 17' boat with a 90hp outboard, I'm using the same amount of fuel as he is.... (If I don't put the hammer down too far :facepalm

Chris......

 

[Jacalore]

Re: MerCruiser 140 Fuel Economy

"The West Australian dhufish (Glaucosoma hebraicum) is a WA fishing icon. It grows to a great size, tastes superb and is targeted by both commercial and recreational fishers."

Perfect!

 

[thumpar]

Re: MerCruiser 140 Fuel Economy

Glaucosoma hebraicum, West Australian Dhufish. Of the sea perch family...

More info on this fish.



Hull shape and material also has a huge bearing on fuel economy. As an example, my brother has a 17' boat with a 90hp outboard, I'm using the same amount of fuel as he is.... (If I don't put the hammer down too far :facepalm

Chris......

I am having that problem going from the 2.5l boat to the 5.7l EFI boat