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Putting Lower Unit in Forward Reverse

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fieldsy

Member
"I've just successfully ch

"I've just successfully changed the impeller on my 75hp mariner, but when we have reassembled everything, we have no reverse and the engine is "clutched" when its in neutral. I've read through the posts on here and it seems asthough we have the gear spline in the wrong position. Could someone advise as to which position the spline should be in for either neutral or reverse.....I'm assuming its a very fine line to get this in the right position????.

Thanks for any/advice help,

Paul"
 
"Hi JB, It ratchets in every p

"Hi JB, It ratchets in every position, thats what doesn't make sense. No matter where I position the gear spline clockwise or anti clockwies, the drive is still "clutched". It doesn't spin freely in any position. Unless I am missing something somewhere. Thanks for your reply.

Paul"
 
"There is definatly a nuetral,

"There is definatly a nuetral, free spin area you must find. If this helps
forward gear = prop rattchet when turned cw
neutral = free in both directions
reverse = prop ratchet when turned cc

find out which one you have, have someone move the control on engine so you know which way you need to turn the shift shaft."
 
"Hi JB,

Thanks for trying t

"Hi JB,

Thanks for trying to help.We've looked at the gear drive shaft (if thats what you could call it) and it turns anticlockwise when the control lever is forward (looking from the back of the boat)

So we assume when you offer the lower segment up to engage the spline that should also be anticlockwise (which makes sense).

...but no matter what way you turn the spline whilst it is on the floor, the prop remains locked wether the spline is clockwise or anticlockwise. Sorry for amking this more difficult in my explanation than it is.I'm sure we are are doing something wrong, but it should be so easy forward position, neutral and reverse, but no matter what position the spline is in, the prop is locked ???

regards
Paul"
 
"lets use cw for clockwise, an

"lets use cw for clockwise, and cc for counterclockwise. The drive shaft (the long shaft) turns clockwise(cw) all the time, in forward and reverse. The item that needs to be adjusted is the small (forward) shaft with the splines. Put a pair of pliers on this small shaft and rotate it, if its feels as it wont move try turning it the other direction. Midway thru its travel is nuetral. Nuetral is when the prop spins freely and when the long drive shaft turns cw without the prop turning. Please try again. John"
 
"Hi JB,

Well, I have tried

"Hi JB,

Well, I have tried again, and done exactly as you suggested, turn the small shaft from full clock wise to counter clockwise (very slowly) and turned the drive shaft and it is not going in to neutral, it remains in forward throughout the whole rotation of the small spline. I'm (and my brother-in-law, who is an engineer), are totlly dumbfounded.


thanks

Paul"
 
"Paul, I have been reading all

"Paul, I have been reading all what is going on here and can't help but wonder if you have pulled up on the shift-shaft enough that it is not engaged at the lower end.

If you can see anything more than the splined end protruding from the bushing (the triangle shaped thing with the two bolts), then you may not be "meshed" with your lower end properly.

Have your tried very slowly rotating your shift shaft and applying some "downward" pressure on it - it may have got pulled out of place...

If you try this and all of a sudden it does drop about an inch, you know that was the problem..."
 
"Hi Graham,

Just been out a

"Hi Graham,

Just been out and had a look, and the only visible point is the splined part.This is what happens if i have the shift shaft in ANY position, clockwise or counter clockwise. The prop turns clockwise when turning the drive shaft clockwise. If I only turn the prop on its own, it ratchets into a positon, ratchets again and so on. The shift shaft position makes no difference whatsoever????

I'm totally depressed
and confused


regards

Paul"
 
"Once the prop is at the point

"Once the prop is at the point of ratchet, I can turn the shift shaft freely with my fingers as though it is not locked into anything and hear it tapping inside from side to side ??

Thats probably not going to help much, but thought I should explain everything
"
 
"Paul, this one is really baff

"Paul, this one is really baffling - did anyone accidently undo the shift-shaft bushing during the water-pump service? maybe??

I'm really reaching here now, because this just doesn't make sense - but there is a shift "cam" which the lower shift-shaft goes though - I don't know that it could go anywhere or get really "disoriented" even if the shaft was disturbed - or maybe it just plain broke - but something definately isn't working right at the bottom of that shaft..."
 
"Paul, have you tried a little

"Paul, have you tried a little extra force turning the shift shaft, it sounds as if its stuck in forward. Look at the shift shaft assembly in the engine, compare the amount of rotation it has when someone moves the controls from fwd to rev. Does it travel farther than you are turning the shift shaft."
 
"Hi Graham,

The impeller re

"Hi Graham,

The impeller replacement was very straight forward, no probs on it at all, and nothing really got disturbed, there were two of us holding the lower unit like a baby.......lol.

Hi JB,

There isn't really a great deal of movement in the shift shaft in the engine. When the prop is on ratchet I can swing the shift shaft approx 270 degrees with my fingers clockwise to counter ckockwise. I don't want to put toooooooo much force on the shaft, just incase


thanks for bearing with me fellas, but this is driving me crazy. Is there such a thing as a clutch dog in there???, could it be busted???, and if so, how the hell do you change it ???

Paul"
 
"Paul, I think the shaft shaft

"Paul, I think the shaft shaft has been turned to far and now has to be re-engauged/turned the other direction. You should not have 270 degrees of travel without it engauging. Figure out which way reverse would turn it and try it once for me. I'll drink a beer with you,if it works"
 
"It's sounding more and mo

"It's sounding more and more like the cam has been dislodged, stripped or something along that line - because yes, the shift-shaft shouldn't be able to pull "out" from the top - it is retained by a clip below the bushing.

Was wondering though if it had got undone in error and allowed the cam to slip from the (place where it lives - can't think of a better way to put it).

Or alternately, got turned too far in one direction and stripped so that the splines on the shaft end are just turning in "hole"......"
 
"Ok, not one to give up, I&#39

"Ok, not one to give up, I've give it one more go.JB looking down on the LU the shaft would turn counter clockwise to go into reverse.

Ok, I've turned the drive shaft and the shift shaft at the same time, and put slighly "more leverage" on the shift shaft fully anticlockwise and the prop is turning freely by hand.....huraaaaaaaaaaaaay you all shout....but the shift shaft is now at max (and more) counterclockwise, and I can't turn it any further. Its 10.30PM in the UK now, so time for a rethink tomorrow. I've got the prop spinning freely, should I put it in and close my eyes and cross fingers. thanks to everyone......but I've got to get some shut eye now.

regards

Paul"
 
"Yippeeeeeeeeeeeeeeeeeeeeeeeee

"Yippeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee!!!!

Ok, fresh day, fresh start. By putting extra force on the shift shaft anti clockwise and turning the drive shaft, the unit finally went into neutral.The shift shaft would go no further under force, so I assumed that if we put it in we would have no reverse, because the shaft was at maximum.

We offered the unit up to the engine, bolted it back in, tried the gears manually (with no power) and we had F/N/R. We then started her up, and hey presto!!!, F/N/R with power!!!!.

Thanks for all your patience and answers guys, I wouldn't have forced that spline without a bit of encouragement.

Very Happy and pleased, and also for learning a bit more.

best regards

Paul"
 
Oldsaltydog said:
If you want help, start a new thread. This one is from 2007.
Click to expand...
2017 Mercury 60 hp ELPt 4 stroke Changed the impeler all want fine. I in my 4th day trying to reinstall lower unit, will not close up holds out about an inch and a half. Got it to close up once have 100 tries stayed in N could not get it to shift from there . . . ! help[, motor only has 100 hrs in great shpe. Have tried inF/N/R and no luck I,m at the end of the road but don't want to give up
 
There is a risk of major damage.----Put lower unit in neutral.----Put control in neutral.----Assemble making sure shift engages.----An assistant to turn the flywheel SLOWLY may help.
 
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