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Dog clutch spring

J

jes229445

New member
1998 60hp Mariner. I'm having problems going from natural to reverse. I have the lower unit apart and the clutch and gears looks close to new. I try to push the pin in by hand to move the clutch and can't do it. The only way to push it in to engage it to the gear is to put it against a piece of wood and lean on it. Does this sound normal or does it sound like the spring is way to tight. I stripped out my shifter trying to get in reverse. It's always been a little hard to get in R but now it's taking a lot of pressure to get into R. Also with the propeller shaft out should the shift shaft spin freely by hand. I can spin by hand but it takes some force.
 
It is a fairly strong spring.----I believe you can shift that motor all day long from neutral to forward and forward to neutral.-----But when going to reverse the motor must be running or prop turning.
 
The prop does spin. When I go from forward to neutral, it stops spinning forward and starts spinning in reverse. It's in neutral and can stop the spinning with my foot.
 
Sounds to me like your shift linkage isn't aligned properly. The dog just does what it's told assuming everything is otherwise in working order. You are favoring R gear with your linkage...not familiar with that engine so I don't know how the shifter mechanism is connected to the shift rod going down to the LU. If nothing else, the splined interface connecting the shift rod to the shifter stub sticking out of the LU is off one tooth.
 
Just for grins take the linkage loose at the engine and try working the shift lever to see if the issue could be in the control unit or cable.
 
jes229445 said:
The prop does spin. When I go from forward to neutral, it stops spinning forward and starts spinning in reverse. It's in neutral and can stop the spinning with my foot.
Click to expand...

The gear oil will make the prop spin in neutral it doesn't mean it's in gear. If you are shifting into R with the motor not running you can do a lot of damage to the shift shaft as another poster found out. I wouldn't be putting my foot on a prop while the motor is running.
The clutch spring is designed to force the clutch into the forward gear so it takes more force to mate it with the reverse gear.
 
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Quicksilver is talking about me among others that have bent the shift shaft because of not knowing that it would be bent if the engine wasn't running (or you just got lucky that the dogs were lined up right). My boat had sat up for a number of years before I got it and the steering and shift cables loosened up a lot after a bit of running and some lube. I was reading a blurb from Mercury that said that sitting causes more problems than a lot of use and of course maintainance or lack thereof is the another common issue.
 
Looking at the root cause of this problem is the way the rear of the "dog" and front of the R gear are designed. Unlike the built in overrun clutch, like is on F gear rear and front of the dog, R is vertical sided cogs and slots which have to be perfectly (pretty much) aligned for the cog to mate with the slot and slip into it to allot the shift linkage to make it's full travel and the engine to actually be in R gear.

If they aren't aligned and one forces the shift linkage to assume the R position, something has to give and that is/can be bending of the linkage connecting rods/cables, whatever. Rotating the prop while shifting if engine is not running, while applying light pressure to the shifter will allow the two to find each other and slip together allowing the mechanism to move completely to the engaged position.
 
About 52 years ago I learned to turn the propshaft when shifting most motors.----But I know that many folks today are not aware of the concept !!
 
You can see the reverse dogs in this cutawaylushiftsetup.jpgif you look really closely.
I'm assuming that they used square dogs because in R the prop will move outwards and the ramp type would ratchet.
 
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In 1996 thru 2005 60 Jet thru 125 2 strokers they use cogs and slots, locking you in R. Can't vouch for anything else. Originally these engines used 3 but later on they went to 6 for greater reliability as sloppy shifters (operators) would wear the corners off and the things could/would jump out of reverse. Engines with 6 have a 45* diagonal cast into the top of the rear of the LU rather than being straight across for identification.

The rear of F gear is sawtoothed, the overrun clutch used in decelerating, and if you spin the prop by hand, engine off, in F gear you can see the prop walk up and down the ramps causing the prop to move back and forth with respect to the LU casting an ⅛" or so.
 
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First of all, thanks to everyone that responded. After reading everything I decided to start over. I put it all back together and ran the motor and it was still very hard to put it in reverse. I disconnected the cables from the motor, the shifter worked great. Next I hook the cables back up and dropped the foot a few inches (till it was clear). Went back to the shifter and it was still running smooth. So I feel I'm back to the lower unit. Watched a video and a guy propeller shaft in his hand and pushed the pin (the pin the pushes the dog back) with the palm of his hand. I can't do this. I have to it against a piece of wood. I know the spring is suppose the get weaker with age, but. Plus from the time I bought the boat shifting to reverse has always took a little muscle. I wonder if the previous may have changed it with the wrong one?

When it is in reverse it runs fine and comes out fine. Just seems to hard to get there.

To respond to comments left. I have not shifted to reverse without the motor running.
 
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