Gear help with 71 115 merc.

[cell]

So Im slipping in reverse.After searching the forum the clutch dog looks bad.I take the lower unit off,and pull out the guts.Dog has a little wear on it....doesn't look like it should be a problem.After going through the motions,and getting everything back together on the bench reverse locks up now....on the bench.I go out to the boat,and install the lower end...reverse slips now.Both times Im spinning the prop bye hand,and on the boat Im shifting by hand...no cables.This is driving me nuts lol.Any input?

How far do the dog and gear cogs inter mesh when you shift into reverse(on the boat)?all the way,or just a little?

Thanks, guys/gals

 

[emckelvy]

Re: Gear help with 71 115 merc.

You may have to pull it back down again and check the shift shaft cam and shift plunger for wear. If these parts are worn you may not get proper reverse engagement. If the edges of the shift clutch and edges of the reverse gear "ramps" are worn, you'll probably need to replace both parts. But be sure to check the plunger and shift cam, I've seen the tips of the shift plunger worn out and reverse suffers the most.

Another thought, the gearcase threaded cover has something like 150 ft-lbs of torque on it. You have to be sure it's tight enough to fully seat the propshaft bearing/reverse gear carrier into the gearcase. If the carrier has backed out at all or isn't fully seated, you're gonna have problems with reverse.

Let us know what you come up with.........ed

 

[cell]

Re: Gear help with 71 115 merc.

"Another thought, the gearcase threaded cover has something like 150 ft-lbs of torque on it."

Bingo...The key that holds the bearing housing wasn't letting me torque the nut good. I noticed it was chipped(previous owner.I never had reverse since I owned it.)So I took it apart again,resembled it with out the key(Ill be sure to put one in),and I got a good torque on it.Lo, and behold there was reverse.Nice and solid....Now to find a key that fits the gear case.....


Thanks, for the input Emckelvy.Much appreciated.

 

[emckelvy]

Re: Gear help with 71 115 merc.

Cool. Congrats on finding that, not an easy thing to spot, especially when a Previous Owner buggers up the parts!..........ed

 

[cell]

Re: Gear help with 71 115 merc.

update:Took her out today....she has reverse now

 

[jetset9c1]

Re: Gear help with 71 115 merc.

Where did you find the key for the cover? I'm having a hard time finding that tool. Mercury lists it as 91-53126 and Sierra doesn't have a cross referenced part number.

Thank you in advance!

 

[cell]

Re: Gear help with 71 115 merc.

I just made one that fit better.

 

[AMD Rules]

Re: Gear help with 71 115 merc.

I think jetset is referring to the gearcase cover 'tool' used to remove the nut.

Some people just hammer on the nut, and other people get creative and make a tool. Once you remove the locking tab, the nut isn't too hard to remove.

 

[jetset9c1]

Re: Gear help with 71 115 merc.

I did get it off ok, it's back on I'm worried about.

 

[jetset9c1]

Re: Gear help with 71 115 merc.

I apologize, I get what you meant now. The little key that prevents the bearing carrier from spinning.

Did you have a tool to re-tighten the ring nut holding it all together?

 

[cell]

Re: Gear help with 71 115 merc.

No service tool.......I used a punch and a hammer...very carefully.