1975 merc 850 lower unit and it's idiot owner... ME

countryboy26047

Petty Officer 1st Class
Joined
May 25, 2012
Messages
303
Hi everyone.. so I realize it's been a REALLY long time since I've posted here and I suppose there's "decent reason" which also leads me to this post... I am willing to admit and accept right now that I already know I am in fact, an idiot! lol Anyhow, I have gotten myself into quite a predicament.. I have a 1975 Merc 850/85hp outboard on my old ugly boat. Anyhow, year before last, I started losing reverse and after some troubleshooting, decided that the clutchdog was bad. I ran it like that for the rest of that year. Then last year, I finally decided to pull the LU off and replace what needed replacing. Well, problem is that I work an average of 4-5 16hr days a week and just have not had the time to get any farther than dropping the LU. Now my issue is, after over a year I've decided to MAKE the time to fix this thing, but problem is (and here's where I am an admitted idiot) I have now managed to lose some of the bolts/nuts that I had taken off...


Now, keep in mind that I am pretty mechanically inclined, but certain things such as the missing bolts/nuts along with not having the specialty tool to remove the locknut inside the hub. I guess my question is, I want opinions and maybe advice as to whether or not I should take the headache path of trying to find/order the bolts/nuts I need and continue trying to get it torn apart/rebuilt, or does anyone know where I might find a good working LU for this motor that I could just hopefully bolt up and run... Sorry I drug this out so long when it seems sort of pointless, but I'm at my wits end with this thing and all I want to do is get to have that enjoyment of cruising the river with my family.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,105
Gee, That gearcase has 5 nuts and a bolt. The nuts are fine-thread, (probably) 3/8" stainless nylon locknuts. They should be easy to find. The bolt was stainless steel SAE thread. likely 3/8" as well. Any gearcase from a early 70's to mid-80s inline 4 or 6 motor will fit. The IL4 motors had a different gear ratio, so those are best for your replacement.

Rebuilding those gearcases takes some special tools and know-how. Replacements are probably easier.

If it were me, I would reassemble and enjoy a summer on the water, without reverse.
 

countryboy26047

Petty Officer 1st Class
Joined
May 25, 2012
Messages
303
Thanks Chris. Since I suddenly have this insane urge to get this thing back on the water after 2 yrs, I ended up going home from work the other night and going through every single container I have of loose nuts/bolts and ended up finding the damn original ones I took off! All except for the prop tab washers and nut which I plan on ordering a kit for those. I also have decided that I am going to try my hand at rebuilding the LU, along with pulling the boat in my shop this winter and hopefully keep the courage I have right now and restore it. I pretty much came to the realization chances are I won't have this thing on the water this year because the river I mainly use it in I pretty much HAVE to have reverse in order to launch and load so I'm going to take my time and do this thing right.
 
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