Any 7.5 hp reinstall lower unit tips

[shawn.54]

Changed impeller on my 7.5 Mercury having trouble getting things lined up. Any tips on how to this would help greatly.

 

[shawn.54]

Ok after stopping to ask for help went back odor one more try and it went right together thanks

 

[SuperEnzo]

What year 7.5 do you have? I have a 1977 Mercury 7.5 and I'm having trouble finding the lower unit drain and vent seals
-Ethan

 

[tpenfield]

Ok after stopping to ask for help went back odor one more try and it went right together thanks

Glad we could help

I find that the Lower Unit on my 1969 7.5 sometimes needs a bit of persuasion when reinstalling . . . I think the front bolt/stud gets hung up going thru the upper casting.

 

[shawn.54]

Mine is 83 just had to wiggle it and turn prop

 

[Dekker500]

Have you tested it out since you got it back together?

Hearing that you turned the prop, you will want to verify that when your unit is in neutral that your prop turns freely in both directions.

Why? Because I discovered that turning the prop during install can shift the lower unit out of forward, so when you bolt things back together, neutral-on-the-shift-lever is actually forward gear! Makes for quite a surprise when you start it up...

Instead of turning the prop, turn the flywheel (don't forget to REMOVE the spark plugs).. Good luck!

 

[shawn.54]

Works well in a garbage can full of water forward and reverse and neutral may have been lucky.

 

[shawn.54]

Tested It today ran great after 15 plus years off duty is on a 14R Sea nymph does a great job noticed a "Troll" leaver on top of clamp bracket. What is this and how does it work? Thanks

 

[tpenfield]

The lever swings a bracket down so that the motor can be tilted up for shallow water. Sort of a basic trim feature. I find that the lever does not work all that well and you have to fuss with it in order to get the lever/bracket to engage and release.

 

[shawn.54]

Ok that was the first time I saw it. Thanks for the help

 

[shawn.54]

This motor shares a lot of parts information with 9.8 could a mecurey guy tell me how similar the are?

 

[60sboater]

I did this to my '73 9.8 and it pumps well except at lower engine speeds. I need to pull the PH and check the plastic washer that can distort and restrict flow and also look at the water passages. Mine has the same bore and stroke as a 7.5...maybe the carb is the only difference,not sure.

What year is yours?

 

[shawn.54]

1983 with little use

 

[60sboater]

Sorry,just noticed you'd already posted the year. My Seloc manual,1404,shows the 7.5 and 9.8 in '83 also have the same bore/stroke and displace 10.9 cubic inches. Maybe it's just the jetting/carb. Maybe you can post a topic asking that question. Have fun.