1983 Mercury 7.5

kojack65202

Cadet
Joined
Aug 19, 2017
Messages
6
Had to replace the impeller. Completed that but I can't get the lower unit back on. Stops within an inch of seating. I'm not very knowledgable but I always try. This is my third engine I've jacked with so not much experience. I took it apart in neutral and haven't messed with it while apart. Suggestions?
 

RCO

Petty Officer 1st Class
Joined
Jun 15, 2016
Messages
350
Make sure the water tube is lined up, and that the grommet isn't folded over. Most likely the crankshaft splines aren't lined up. You can pull the starter rope slowly while pushing up on the lower, or shift it into gear and rotate the prop.
 

tpenfield

Moderator
Staff member
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Jul 18, 2011
Messages
18,168
+1 to the above. I found that my Merc 7.5 lower unit was a bit stubborn going back on. Just make sure things are lined up and use some mild wiggling persuasion.
 

kojack65202

Cadet
Joined
Aug 19, 2017
Messages
6
Thank you gentlemen. I was able to get it done today by rotating the driveshaft in small increments. Once together, there was gas seepage from the starboard side of the carberator. Three of four screws were loose. I can see that it would rattle things loose. Would a lock tite product be ok to use? Tightened down and fuel line replaced, it started and impeller functioned correctly.
 

tpenfield

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Staff member
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Jul 18, 2011
Messages
18,168
I recall noticing the same when I first got my 1969 Mercury 7.5, the screws on the carb were a bit loose and the bowl was leaking. I tightened the screws and it has been fine since. Loctite would be OK as well.
 
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