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2004 MERCURY 115 2-STROKE

J

Jayeamans

New member
I am about to purchase a boat with this motor on. The previous owner had the oil reservoir bypassed and now mixes his oil and gas when filling. What is the correct ratio? Or easier, how many gallons per 1pint of oil?
 
The ratio is 1 part of TC-W3 (Two Cycle-Water craft rated, 3rd iteration) or 1 pint of oil to 6 gallons of gas a 1:50 ratio. I use Pennzoil brand I buy in the Walmart Sporting Goods section. While at the store I go over to the automotive section and get a can of Sea Foam and mix the recommended 1 oz per gallon of premix. I haven't been into my carbs for over 10 years and still have no problems. Plugs last forever.

I disconnected the oiler in my 2002 90 and 2002 115 with rhe reason being that my engine sits up most of the year and getting these Merc 2 strokers enough fuel in the carbs to light off the engine after long periods of sitting up has been a problem for me. With the built in oiler, if the crankshaft is turning the oil is entering the fuel hose in the engine.....gasoline not necessarily....and yes I know how to start these engines. This causes hard, usually smoky starts. With premix, the fuel-oil ratio remains constant and starts are much faster and cleaner.

I am 82 and not what I used to be so I mark adjacent to the fuel inlet on the boat to pre-mix so that I don't forget. Have I ever thought about going back (replacing the oil pump gear).....nope.
 
Texasmark said:
The ratio is 1 part of TC-W3 (Two Cycle-Water craft rated, 3rd iteration) or 1 pint of oil to 6 gallons of gas a 1:50 ratio. I use Pennzoil brand I buy in the Walmart Sporting Goods section. While at the store I go over to the automotive section and get a can of Sea Foam and mix the recommended 1 oz per gallon of premix. I haven't been into my carbs for over 10 years and still have no problems. Plugs last forever.

I disconnected the oiler in my 2002 90 and 2002 115 with rhe reason being that my engine sits up most of the year and getting these Merc 2 strokers enough fuel in the carbs to light off the engine after long periods of sitting up has been a problem for me. With the built in oiler, if the crankshaft is turning the oil is entering the fuel hose in the engine.....gasoline not necessarily....and yes I know how to start these engines. This causes hard, usually smoky starts. With premix, the fuel-oil ratio remains constant and starts are much faster and cleaner.

I am 82 and not what I used to be so I mark adjacent to the fuel inlet on the boat to pre-mix so that I don't forget. Have I ever thought about going back (replacing the oil pump gear).....nope.
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Well thanks for the advice. I usually use that Chemtool B12 instead of Seafoam, just because it's a little cheaper, but works just as well. Hopefully I let the boat sit up too long without using it. Bad gas can cause problems.
 
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