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1969-1973 Mercury 4hp Outboard Lower Unit Stuck

P

Promacta

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Hello, I purchased a mercury 4hp outboard to fix up and use. I am unsure of the exact year, but I know it falls between 1969-1973. I got the motor running again after cleaning the carb and fuel pump. However, the motor does not pee and I suspect the water impeller needs to be replaced (almost positive I found a broken fin on the ground when I was working on it). I have removed the 2 bolts to remove the lower unit. However, the lower unit does not budge at all or separate. I watched a couple videos on YouTube with the same motor and they were able to get it off doing exactly what I am doing. Anyone have insight on why the lower unit will not separate and drop?
 
Folks fail to understand the concept of maintenance.------Lower unit must be taken off routinely to grease splines on top of driveshaft.-----Water has likely gotten into the splines.-----Oxygen joins with the steel to form RUST in there.----There is now more material in there than before.------It jams up solid for that reason.-----I have rigged up pullers to separate motor lower units in this predicament.
 
I am aware of this. However, it was a motor that I just purchased 2 weeks ago. What are your recommendations for this situation?
 
You need to figure out how to get penetrating oil to the driveshaft and crankshaft joint. I suggest hanging the engine upside down by the lower unit. you just need enough separation to be able to spray the driveshaft with penetrating oil and have it gravity drip down the crankshaft spline. obviously, you just need to hang it enough the clear the floor with a piece of carpet or a cushion under it , and 1/8"-1/4" is all you need so the engine won't get damaged in it starts to separate. Do not start prying or beating on the lower unit to try to get it off. Let gravity to do the work. Lots of patience here. This may take a week or so.
 
I have no idea what tools are in your workshop.----No idea as to what level of ambition you have.-----I would rig something ( see post #2 ) up to pull it apart.----Perhaps use my truck to pull it apart.----Sorry to be blunt here.
 
fitz73222 said:
You need to figure out how to get penetrating oil to the driveshaft and crankshaft joint. I suggest hanging the engine upside down by the lower unit. you just need enough separation to be able to spray the driveshaft with penetrating oil and have it gravity drip down the crankshaft spline. obviously, you just need to hang it enough the clear the floor with a piece of carpet or a cushion under it , and 1/8"-1/4" is all you need so the engine won't get damaged in it starts to separate. Do not start prying or beating on the lower unit to try to get it off. Let gravity to do the work. Lots of patience here. This may take a week or so.
Click to expand...
I am attempting this now before I do anything else. Although I am doubtful it will do anything as there is no separation between the lower unit
 
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