5w-30
The recommended spark plug for a 1992 model, 200hp Mercury 2 stroke carbureted outboard, is an NGK BU8H. This is a perma-gap type plug, so no gap setting is required.
what type oil to use on 4stroke 2.5mercury outboard
Premium gasoline
If the horsepower of your Mercury outboard lower unit is 75 and below, SAE 80W90 Gear Lube is recommended.
2 stroke-NOT outboard, but the same type such as used in chainsaws
The Mercury outboard 4.5 with serial number 4273176 was created in two type mode which are the "M" and "ML" model. Both model types were manufactured in 1975.
Mercury 1984 6 cylinder L6 what type & size of starting battery is required
The 5 hp Mercury outboard requires no special type gear oil. General recommendation is for a GL-5 class lubricant, i.e. hypoid 90w. Most any of the oem, or aftermarket gear lubes, manufactured for outboard use, will work just fine.
The 1976 model, 115 hp Mercury outboard, requires a 50:1 fuel to 2 cycle oil ratio. This is roughly one pint of 2 cycle oil, to six gallons of fuel. The use of 4 stroke type motor oil is not recommended, nor intended, for fuel / oil mix.
you need a minimum of 87 octane gas
I use 80 weight gear oil.
The fuel mixture for a Yamaha 40 hp 2 stroke outboard engine is 50:1, gas, oil mixture. You should use new gas when you get the engine ready for the season.