The 1973 model, 7.5 hp Mercury outboard, requires 6.8 oz. of gear oil.
22.5 fluid ounces (or 666 ml's) per our 1994 Mercury 125 outboard manual.
If the horsepower of your Mercury outboard lower unit is 75 and below, SAE 80W90 Gear Lube is recommended.
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.
For a 90hp Mercury two-stroke outboard, you should use a high-quality lower unit gear lube specifically designed for outboard motors. Mercury recommends using their own brand of gear lube, such as Mercury High-Performance Gear Lube or Quicksilver Gear Lube, which offer excellent protection against wear and corrosion. Always check the owner's manual for specific recommendations regarding viscosity and any additional requirements.
outboard motor will start and idle, but dies out under load
Mercury® Marine High-Performance Gear Lube from Basspro
motor shuts off when put in gear sometimes
I had used a high performance gear lube quick silver marine lubricant it is not expensive and works very well
For a Mercury outboard 2-stroke motor, it's recommended to use a high-quality lower unit gear oil specifically designed for marine applications. The typical choice is a 90-weight gear oil, such as Mercury's own High Performance Gear Lube or similar products that meet API GL-5 specifications. Always check your owner's manual for the exact specifications and recommendations for your specific model.
No as all the inline 6 cylinder motors are a 2:1 ration and all the small inline 4 cylinder are 2:3:1 ratio
I am assuming you must be having more problems than just putting the lever back into neutral right. Dont worry my Mercury 9.8 is all screwed up to.