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Kicks out of reverse

N

nemer

Contributing Member
1979 175hp v6 mariner shifts into reverse ok, but if I give it some gas it pops out. Is the gear and or clutch shot? If so, does anyone know the part number or type of gear I need to buy?
 
serial #5190703

Even though I set the linkage by finding Nutral with no clicks, it seem to be to close to shifting into forward. I hardly move the lever off center and forward grabs. I have to pull a lot farther back to find reverse. The throttle cable preassure is minimal to hold it on idle, but it just doesn't feel right when I shift into reverse.
 
Has this motor been apart recently? Is this something that it just started doing all of a sudden or, gradually has gotten worse over time?
 
Try this: Grab the prop and see how much fore and aft motion the shaft will allow. If more than a few thousandths, that is too much.

Jeff
 
Have you checked to see if the upper linkage is worn out.

The motors old and up in the lower cowl the upper shift shaft (linkage) has a couple of "latches" and at least one wear plate (all small spring type steel) that kinda (clicks) the linkage in/out of gear when you shift (I'm just talking about the linkage end here, not the gears controlled by the lower shift shaft).

Anyhow, if one of these latches is broken or worn, or the wear plate is worn, a bit of torque in either forward or reverse (respectively) can be enough to "kick" it out of gear.

Quite a few merc's have a little cam on the upper shift shaft and the spring steel latch on them does fail as they get old, resulting in the same symptoms.

Your set-up is a touch more complicated than the simple cam, which is why I would at least take a look at it.

With the motor in gear (reverse since it's your problem at the moment), but the motor "not running", and then try Jeff's suggestion of grabbing the prop - torque it (by hand) back and forth a bit an see if you can get it to pop out of gear - if you can, get an "assistant" to hold the linkage under the hood and try again...
 
galamb said:
Have you checked to see if the upper linkage is worn out.

The motors old and up in the lower cowl the upper shift shaft (linkage) has a couple of "latches" and at least one wear plate (all small spring type steel) that kinda (clicks) the linkage in/out of gear when you shift (I'm just talking about the linkage end here, not the gears controlled by the lower shift shaft).

Anyhow, if one of these latches is broken or worn, or the wear plate is worn, a bit of torque in either forward or reverse (respectively) can be enough to "kick" it out of gear.

Quite a few merc's have a little cam on the upper shift shaft and the spring steel latch on them does fail as they get old, resulting in the same symptoms.

Your set-up is a touch more complicated than the simple cam, which is why I would at least take a look at it.

With the motor in gear (reverse since it's your problem at the moment), but the motor "not running", and then try Jeff's suggestion of grabbing the prop - torque it (by hand) back and forth a bit an see if you can get it to pop out of gear - if you can, get an "assistant" to hold the linkage under the hood and try again...
Click to expand...


Thanks! Ill give it a try.
 
It does seem to be the upper linkage, When I torqued the prop it clicked out of gear, the slip sounded like it was part way up the shaft. Does servicing this problem require removing the power head. Could I have bent something when I changed the impeller? The unit didn't seem to slide into place like my old inline six did? I had to tighten the bolts to draw the lower unit to the exhaust housing. I figured that was because the water pickup sleeve was messed up.
 
Your lower unit is a pin shift just like a Inline motor, usually when they jump out of reverse its one or more of the following: shift cam worn, follower worn and if its been doing this a while the clutch dog ramps and ramps on gear will be rounded.
I had to tighten the bolts to draw the lower unit to the exhaust housing. I figured that was because the water pickup sleeve was messed up.
Click to expand...
This aint good as you could have damaged the shift rod ...
Grab the prop and see how much fore and aft motion the shaft will allow. If more than a few thousandths, that is too much.
Click to expand...
On this model should be about .050.
 
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