About 300 lbs.
The 1977 model, 20 hp Mercury outboard, requires a 50:1 fuel to oil ratio.
Merc 850 854590512 thru 4831998 1977
The recommended spark plug for the 1977 model, 7.5 hp Mercury outboard is a Champion L78V, or NGK BUHW-2. Both brands are Perma Gap type plugs, with the Champion being the manufacturer supplied plug back in 1977.
A 1977 Johnson 175 hp outboard motor typically weighs around 400 pounds (approximately 181 kg). This weight can vary slightly based on specific model variations and configurations. It's always a good idea to consult the manufacturer's specifications for the exact weight of a particular unit.
I just purchased a 1977 merc 7.5 horse and the mechanic said to use 4 ounces of oil per gallon of gas.
50to1
40to1
The Gap is .030
1977 according to SELOC manual
1977
Mercury outboard serial number 1897280, is a 1966 year model, 50 hp. A listing of serial numbers and model years can be found at the link below. Your unit is listed as a 1977 with these possible models: - E (electric start) - L (long shaft -20") - M (manual rope start)