Wrong screw on the lower unit pulled

JLRos

Cadet
Joined
May 13, 2013
Messages
7
I have a Johnson 150 v6 1985 (J150TLCOS). While a attempting to change the lower unit oil I unscrew the middle screw in the lower unit, the phillips one, DUH. Later i realized my error and unscrew the correct ones and proceed to change the oil successfully. I put the middle screw back after a few hours of letting the lower unit drip all the oil out, never changed gears but moved the propeller manually. After i finished started the engine and changed gears and saw the propeller moving forward and reverse apparently fine, later i noticed that the gear handle takes more effort to move forward position, still, is shifting gears. Question: even if i noticed shifting gears out of the water it is possible that the screw is out of place? does moving the prop manually although not changing gears could have moved the internal piece and i can damage costly pieces inside the lower unit with just use? or Im out of the woods is all fine and all is mental like my wife's said?

Thanks in advance for your responses
 
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racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,051
That screw is in there to lock the bearing in place.-----Just install it again and make sure it does not leak.-----It has a wee o-ring on it.
 

JLRos

Cadet
Joined
May 13, 2013
Messages
7
Ok took me some time, few months, to finally get the boat on the water, rode the boat yesterday completely fine, forward or reverse without a single problem, stiffness on gear handle was fixed with some marine grease. Obviously not changing the gears without the screw in place save me from further headaches, lesson learned, watch videos, read instruction and work slow and methodical all good advice for weekend so call mechanics like me. As you can expect my wife actually enjoyed your answers, Nwcove, man you are damm right, still im happy the damm screw didnt cause me a matrimonial fight.
biggrin.gif
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
36,051
When that screw is out you can change gears all day long and nothing will happen.-----The screw is there to prevent the bearing from going out of position during full throttle operation.--I believe high oil pressure it that bearing is the reason for that screw,---Early , early lower units did not have that screw and bearings did move.
 

Vic.S

Rear Admiral
Joined
May 4, 2004
Messages
4,690
And earlier models often have a small screw with a Phillips head near the drain plug that is a pivot/ retainer for part of the shift mechanism.

If you take one of those out and the parts inside move you have real problems.
 
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