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1969 Mercury 40 4hp recoil starter

Colezay

Regular Contributor
I’ve definitely bitten off more than I can chew with this one. I went to take off my recoil starter on my outboard since it was retracting very slowly. Little did I know, it would perform a rapid unscheduled dis assembly all over my work bench. The spring has unwound although it is still in its slot. What should I do? I’m not sure on how to wind it up again. Should I Give it to my local small engine mechanic and save myself the hassle, or is there an easier way to do this that I’m not seeing.0BCA5B95-2A15-4B81-98E8-0A81F6CA4DEA.jpgF2242B12-4799-498A-A942-DD12CEA8AB10.jpg
 
Order the 1966-1974 Mercury master service manual and learn how to do it. Before I would do that, check the lower unit oil and see if there is anything in it. Those engines had steel driveshafts and shiftshafts that are prone corrosion in the seal area and leak water in and gearlube out which unchecked would destroy the lower unit.
 
Bottom line is.------Do a complete evaluation of this motor any of the junk motors you find before spending beer tokens on parts.-------Check gear oil / water pump impeller / pressure test lower unit / inspect pistons and rings through bypass covers / compression test.
 
Could be there is nothing in there but rust. Has it been sitting around long? Or is it a running motor? Milky lube would mean water....yes. I know you like to fix motors, so the aforementioned pre checks recommended by Racer, are a must.
 
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Near the bottom of the gearcase.----And the vent screw is likely a different one very small and under the cavitation plate.----Not sure why you can't find a drain screw unless it has been epoxied over ?
 
All I could find is a flat head screw about a half an inch above the cavitation plate on the right side. Under the cavitation plate I see a water intake it looks like and a nut on a bolt holding said intake cover on
 
The lower unit vent screw is NOT above the cavitation plate as was clearly stated !!---The drain screw is underneath the " bullet " nose of the lower unit.-----That screw holds the water intake screen and holds the lower unit on.-----I suggest you do some reading on " how to repair motors " .----Or spend some time on you tube channels there are some very good tutorials and some that are very entertaining too.
 
I found it. I’m assuming that bolt I found above the cavitation plate is the vent screw as I am 100% sure there is no other screws. What fluid do I use?
 
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Good thing I checked the lower unit fluid before continuing. About a half a cup of water came out follow by dark black tar like oil. I’m gonna put her back together and sell her. I also have a 1973 mercury 40 4hp in a lot better condition. Checked the oil on the 73’ and it was a brown oil, no water or metal shavings.
 
Bingo....good call Racer and Fitz. It might be okay, depending on how it looks and SHIFTS. Could be the leak just started and rust hasn't formed yet. I suggest remove lower unit, then water pump, and inspect upper shaft bearing as well as shaft area where seal rides. Could be the bearing is still good. Then you can buff up shaft and install new seal.....setting it a little bit lower so it can ride on a fresher part of the shaft. Then install a new pump/impeller, grease splines....and put her back together after a pressure and/or vacuum test.
PS. There is another post here (currently), covering this same subject.
 
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It shifts fine and spins over good as well. Also please link me to that post :p. I might fix it but then I also have to deal with that recoil starter. I could make my money back by parting it out if I need to.
 
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