87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

Adam F

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Jan 13, 2014
Messages
6
Hi. I'm new. So please be gentle.

I recently removed the lower unit and replaced the shift shaft seal in my 87 Merc 35 HP. I was careful to keep the shaft in place when I removed the bushing, made sure it didn't move clockwise or counterclockwise. Before reinstalling it, I even made sure that it was still in neutral as when I removed it (prop spun freely), one turn counterclockwise put it in forward (prop clicked when moving counterclockwise), and one click clockwise from neutral put it in reverse (prop wouldn't move). Then, I reinstalled it in neutral (shift shaft was in neutral). I tested the controls. Moved lever to forward (prop spun counterclockwise with the same clicking) and then back to reverse (prop stayed put). Shifting the lever was noisier than before I did the work, but everything seemed to check out. THEN I started the motor. While the control lever was in neutral, the prop ran as if in forward. When I pulled the lever to neutral it grinded a bit and the prop started spinning the other direction. Does anybody have any idea what is going on, or how I should proceed to fix it. Thank you very much for any input.
 

Adam F

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Jan 13, 2014
Messages
6
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

One more thing. When I have it all back together and in neutral (motor off, prop spinning freely) I can move the prop by turning flywheel a bit.
 

racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,401
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

You may need to adjust the shift cable.---Did it work properly before ?------------------Now in forward gear it should click when turning prop CLOCKWISE and lock up turning prop COUNTERCLOCKWISE.
 

oldman570

Lieutenant Commander
Joined
Mar 25, 2011
Messages
1,615
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

When testing your work with the motor on muffs, to supply water to the motor and the motor running, you may have some grinding of the gears as there is no load on the motor. The motor has to be under a load with back pressure on the exhaust and the motor at operating temp or will not idle down to the recommended RPM. This will cause the gear grinding you have. Placing the motor in the water or test tank/barrel is the best way to test any work and check for correct settings. JMO
Oldman570
 

Adam F

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Joined
Jan 13, 2014
Messages
6
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

You may need to adjust the shift cable.---Did it work properly before ?------------------Now in forward gear it should click when turning prop CLOCKWISE and lock up turning prop COUNTERCLOCKWISE.

Thanks racerone. I'm sorry. I goofed up. When I put it all back together but don't get it running the controls work fine--in forward the prop spins CW, in neutral is spins freely, in reverse it locks up. But as soon as I get it running (using just a muff for water in a bucket yet), even though it's in neutral the prop runs in forward. When I goof around with the controls it won't go into neutral, just reverse. Still think it might just be the shift cable?

Again, thanks for your time and experience. This is the first outboard I've worked on, did work on a nuclear propelled submarine 20 years ago. But this little 185 lb thing is kicking my butt.
 

Adam F

Cadet
Joined
Jan 13, 2014
Messages
6
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

When testing your work with the motor on muffs, to supply water to the motor and the motor running, you may have some grinding of the gears as there is no load on the motor. The motor has to be under a load with back pressure on the exhaust and the motor at operating temp or will not idle down to the recommended RPM. This will cause the gear grinding you have. Placing the motor in the water or test tank/barrel is the best way to test any work and check for correct settings. JMO
Oldman570

Thanks oldman. I'll use a bucket next time I get a chance to work on it and see what happens--hopefully tomorrow.
 

jslu

Seaman
Joined
Jul 31, 2010
Messages
74
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

Adam

You made no mention as to if you took notice of the splined shift cam position on the shift shaft. The cam has to be removed in order to get to the shift shaft seal. If it was not put back in the correct "neutral" position during your re assembly, then you could have the shifting problem that you are describing. I do all my lower unit removals of the 35 HP motors in the forward gear. Works for me all the time.

John
 

Adam F

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Joined
Jan 13, 2014
Messages
6
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

John,
Thank you. I did replace the shift cam but in the neutral position. I'll try it in the forward position today and see what happens.
Adam
 

Adam F

Cadet
Joined
Jan 13, 2014
Messages
6
Re: 87 Merc 35 HP - Reinstalled lower unit, can't shift into neutral

Thank you everyone. Using a trash can instead of a muff did the trick. Took it out the other day and it ran like a champ.
 
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