Logo

Early Evinrude Fuel Usage

cdn1972

New member
I am getting ready to turn my 53 bigtwin 25hp to a one line fuel system and rebuild the carb at the same time. I have replaced the coils, wires and points so ignition will be fine. I have read here and everywhere early twin evinrudes get lousy fuel economy and a friend with a 53 10hp agrees. Even well tuned it is poor. When rebuilding the carb are there some suggested mods to reduce the fuel usage without creating a lean condition or is it what it is? I will be using modern synthetic oil and no ethanol fuel. The reason i ask is two fold, one wasted gas on these old engines usually ends up in the lake and I am using the 25 on a small hydro with a very small built in tank for pleasure running not racing.
Ideas?

thanks

Kevin
 
Use minimum 3 gallon fuel tank.----There is more to fuel usage than the carburetor !--------Good rugged motor, but thirsty.
 
Use minimum 3 gallon fuel tank.----There is more to fuel usage than the carburetor !--------Good rugged motor, but thirsty.
The built in tank i am building should hold about 2 to 2.5 gallons, I will be running in a smooth bay so im not worried about being far away from the dock to refuel. I just want the best for the lake and burn for my buck. What else other then proper tuning and the carb?
 
Still have one of those motors in the basement that I used to run on an 11' runabout ( 40 years ago ) great tough motors.------------You will need to find the proper propeller to keep the revs down,-------I believe 14" was the highest pitch available from OMC.---------Might want to look for a bronze 2 blade on E-BAY.
 
gas usage was low priority when those motors were designed and built....you could fill up a 6 gallon tank including oil for around 2 bucks..dont compare your gas usage to the 10hp...they are two different animals in that regard...check the compression and do the things mentioned above and if you dont see gas and oil droplets showing up on the water then you will be getting about the best you going to get on that engine..i think all of us are aware with todays gas prices just how expensive running an outboard is...get a 6 gallon tank and enjoy using a good vintage motor...price a new one and a little extra for gas will not seem so important...
 
Thanks for the replies guys, I will be starting to re-assemble the engine later in march when it warms up a bit in Southern Ontario.
 
Thought you might enjoy these pictures of the military version of this outboard...check out the 360 degree reverse and the shielded plug wires
PB170008.JPGPB170009.JPGPB170010.JPG
 
dont most 2 strokes, average 10% of the motor per hour at wot? i.e. that 25 would be using about 2.5 gall / per hour at wot? a 10 would be only 1 gall / per hour. huge difference.
dino
 
true but remember this motor is 60 years old...and if its a military version there is a good chance the lower unit is beefed up with a possible ratio change....
 
Back
Top