Starting an 57 Evinrude 7.5 fleet win after many many years of storage.

motomanmatt

Cadet
Joined
Dec 31, 2023
Messages
11
I bought this engine out of a estate sale. Looks brand new, honestly. If it's been run, it's certainly hasn't been much. Hardly a scratch or any indication of where externally. Carb bowl is spotlessly clean. I've converted the motor to run on a modern pump and fuel tank system. I've sprayed seafoam in both cylinders and let it sit overnight. I've topped up the lower unit. Anything else I should do before I try to fire her up? Any advice is appreciated. Thanks in advance.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,818
Have you checked to see if spark will jump a gap of 1/4" or more on a test device ?-----It will need a new water pump impeller as well.
 

Nordin

Commander
Joined
Jun 12, 2010
Messages
2,555
Do as racerone says, check for spark and if it jumps at least 1/4 in in atmosphere.
Pull the flywheel and check the coils, it is common on old OMC with magneto ignition that the coils are cracked and roten.
Clean the points and set the gap at 020.
 

TN-25

Chief Petty Officer
Joined
May 27, 2008
Messages
618
Yes, don't skimp on the oil in the gas. The Fleetwin is a bronze bushed motor and it needs the oil. They called for 16:1 oil/gas ratio back in the day when you would mix straight 30 weight non-detergent automotive oil in with the gas. Really old tech.
You might get away with 24:1 mix with modern TC-W oil or synthetic, but the bushings still need the oil film thickness. Be generous with the oil.
 

motomanmatt

Cadet
Joined
Dec 31, 2023
Messages
11
Yes, don't skimp on the oil in the gas. The Fleetwin is a bronze bushed motor and it needs the oil. They called for 16:1 oil/gas ratio back in the day when you would mix straight 30 weight non-detergent automotive oil in with the gas. Really old tech.
You might get away with 24:1 mix with modern TC-W oil or synthetic, but the bushings still need the oil film thickness. Be generous with the oil.
Great tips, everyone! Thank you!!
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
37,818
The 5.5 / 6 HP from 1961 to 79 have bronze bushings for the main bearings on the crankshaft.----At 50:1 mix I rarely see any damage.----In fact most look just as good as new.
 

TN-25

Chief Petty Officer
Joined
May 27, 2008
Messages
618
The 5.5 / 6 HP from 1961 to 79 have bronze bushings for the main bearings on the crankshaft.----At 50:1 mix I rarely see any damage.----In fact most look just as good as new.
I did not know that! I figured by the time for 1965 they became 6 horsepower in the 50:1 era they would have bearing races.

The 3 & 4 horse motors (which I love) were bronze bushed through 1977. I'd love a fully-jewelled '78 as the '79s began with European-style integral gas tanks (in use in Europe since '72).
 

oldboat1

Fleet Admiral
Joined
Apr 3, 2002
Messages
9,612
We don't know use or overall condition. I use the originally recommended ratios, with factory recommended tuning.
 
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