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1984 Mercury 50hp EL - QUICK QUESTION

S

surveywaters

New member
I have a 1984 50el.
Today I ran it on the muffs and noticed water coming from behind one of the bolts that holds the lower unit to the midsection. It is the bolt nearest the transom on the right when standing behind the boat. Is this normal?

Also, when I crank the engine there is a good 5 second delay before water starts to pee. When I shut it off there is alot of gurgling as the system drains. I replaced the fuel pump a year or two ago. Is this normal?

Thanks guys
 
Thanks Jeff. I assume you are referring to part 2 of my question. I removed the foot and looked behind that back nut, the hole appears to be a result of corrosion. Now I just don't know if there was already a hole that just got bigger. There is no hole behind the nut on the other side.
 
Ok, the shift shaft bushing is corroded and stuck. It broke when I was attempting to remove it (I have the proper tool). Half of the upper section came off, from one tab cut to the other. I think the only way to turn it now is by removing the shift shaft and inserting an easy out. Does the shaft just pull out vertically and can it be reinstalled without disassembling the gear case? Also, what do ya'll think about the easy out idea?

@fastjeff
 
The bushing holds the shifter shaft in, and if you yank it out (and the shaft comes along) the entire LU has to be disassembled to get the shift cam back on the end of the shaft. Rats! If you're very careful (and lucky) you might be able to remove the bushing without pulling up on the shaft. There's usually a set\ screw to keep that bushing in place. It HAS to come most of the way out before the bushing will.

Jeff
 
The serial # of the motor is 6449981. I have studied the exploded view in the service manual and unfortunately see no set screw, that would have been a bit of hope. The bushing threads in to the gear case. The bushing is omc #23-77631A 2, it is a soft aluminum material, unfortunately, which when oxidized sheared easily. The top of the bushing has two nocks in it that receive a special tool. The bushing sheared from one nock to the other on one side. Now I can see half of the o-ring at the threads. I heated the case around the bushing and attempted to get a purchase on the remaining material with a punch to no avail. Any tips, advice or ideas would be great. The seal is barely secured and will likely leak horribly.
 
Got it. (There's several different designs.)

Here's what I would try: Drill the hell out of that bushing from above--start with a small drill in a bunch of locations, then go to larger drills. Be careful not to bugger up the housing threads. When it's Swiss cheesed enough, smash it out of there with a sharp chisel, piece by piece. With a bit of luck you'll be able to get it all out, and without destroying the shifter shaft.

Good luck!

Jeff
 
Advise having a helper with a vacuum cleaner keep sucking out the fragments as you go--think dental office!

Jeff
 
Thanks. It's not coming out to well. I don't understand the cause of this. The SS bolts holding the foot on and the water pump in came out with ease; very little corrosion. The aluminum on aluminum has gone so bad that I doubt there will be any threads left in the LU. Bummer.
 
You don't need much threads, for you can screw in a new piece and epoxy it in place. Then drill and set screw it as well. Not much upward force on it.

Jeff
 
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