Cannot get boat to go into forward or reverse after put lower unit back on

Karla45

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I have a 1989 Force 85HP. I took the lower unit off to replace seals because of leak. I got the lower back on and connected everything back up. Now I have no forward or reverse. I had originally marked the positon of the shift rod before I took the lower unit off but the mark is gone so now I do not have that to go by. I also want to say that I have the model that has a two piece shift rod instead of 1, this rod screws into the lower shift rod. Originally when I first put it back on, the prop would not move at all in either direction, so today I screwed it back down and then unscrewed it to get it up high enough so I could put the pin thur coupler & rod and then put cotter pin on, this at least got it to where the prop would spin freely in both directions, which led me to beleive it was now in neutral and the boat shifter is also in neutral and was when I took the lower unit off. What do I need to do to get it to go in forward and reverse. The manual said that I was supposed to screw the rod all the way down and then back out 4 full turns which I had done before putting the lower back on. This obviously did not work. So what do I need to do, screw it in more or back it out?
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

I was able to find some information Frank had posted and it helped me at least understand more of what I am doing. The only part I am not sure about is when he talks about getting positive engagement in forward and reverse( see below i copied his instructions) Right now if I turn the prop clockwise with shifter in forward it will move and it makes a mild click noise and vis versa in reverse. If I start the boat and shift to forward the prop does not move in either forward of reverse. How do I know that I have positive engagement in forward by turning the prop, what will it do? This way I will know which was to adjust the shift rod.

There are two ways to do this: The easy way and Frank's way. I prefer Frank's way but will describe both to you.

The easy way is to look at the area where the engine is attached to the transom. Below the clamps and under the lower engine mount you will see a 1/4 inch rod exiting the casting and held into a cylinder by a pin and cotter. If you remove the cotter and pin, the rod is now free to be screwed in or out.

Since moving the rod down selects forward gear, Screwing the rod out or up will bias the linkage more toward forward when it is pushed down to line up the holes again. Be careful and move it only 1/2 turn at a time. A little goes a long way. So, adjust and replace the pin and check, then adjust again until you get positive engagement in forward yet no noise in neutral, and positive engagement in reverse.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Okay so now I got it adjusted to where the prop spins in forward and reverse. Now when start the motor and put it into forward it makes loud clunking noises and same with reverse. I am not sure if this is normal or not, because I have never put the boat into gear while I had it on the muffs. Is this normal I want to make sure I do not strip any gears? It would seriously help me to know exactly what positive engagment means. For instance, if I have the boat in forward and I turn the prop by hand, which way do I turn it to know I have positive engagement. Is positive engagement when the prop locks and will not move? This would help me greatly in knowing what to do in adjusting the shift rod to the correct position.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

I am starting to get the feeling that I am not going to get any answers on this since I have been asking about this since last week. If my question is not clear please let me know. I have been calling people who have boats and telling them what is going on they do not understand either. The other day I talked to boat mechanic and he told me to just screw the shift rod all the way down and that should be the correct position, but if I do this the prop locks at both directions. I am just about to give this boat away. One thing for sure I will never touch the motor again if it ever gets fixed.

There has got to be somebody who knows how to knows how tell if the forward and reverse gear is positively engaged by turning the prop by hand.
 

hypersniper

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

when you put it in gear do you just push the shifter forward gently or just throw it right into gear? your NOT supposed to put it in gear gently. it will make a grinding noise if you do and do damage to the gears. a positive push into gear is recomended so i may make a clunking sound as it engages the gear. thats the best advice i can offer you . good luck and dont give up and im sure someone with a little better knowledge will eventually help you out.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Okay so now I got it adjusted to where the prop spins in forward and reverse. Now when start the motor and put it into forward it makes loud clunking noises and same with reverse. I am not sure if this is normal or not, because I have never put the boat into gear while I had it on the muffs. Is this normal I want to make sure I do not strip any gears? It would seriously help me to know exactly what positive engagment means. For instance, if I have the boat in forward and I turn the prop by hand, which way do I turn it to know I have positive engagement. Is positive engagement when the prop locks and will not move? This would help me greatly in knowing what to do in adjusting the shift rod to the correct position.

I mainly need to know what positive engagement of forward or reverse means or what to look for when I turn the prop to know if gear is fully engaged. I know what is supposed to happen in neutral. Once I understand this I can do the rest.
 

foodfisher

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Positive engagement means you cannot turn the prop by hand when in gear. Unless you're strong enough to turn the motor over with the prop. Prop should free wheel in neutral. More: No matter how many turns at the joint, when the rod is pushed all the way down you should be positively engaged in forward gear. Prop locked, no turning. When pulled all the way up-locked in reverse. Midway between between=neutral=free wheel. Threading up or down will bias the midway point toward any nonpositive engagement.
 
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Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Okay thank you so much. So when it is engaged in forward if I try to turn the prop clockwise it should feel locked, correct? I think now I know what I might have been doing wrong?
 

foodfisher

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Edited more while you were typing.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Thank you so much that really helped. So I want to make sure I understand correctly now. If I put the motor in forward gear, then manually turn the prop counterclockwise and it locks up, it is correct for forward and vice versa for reverse?
 

foodfisher

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

You got me! Clock/counterwise? If you can't push the prop against the way it has to go to push the boat forward, it's in forward gear, and vise versa. Gnight
 

Frank Acampora

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

102_6458.jpg102_6459.jpgOK! This is a difficult concept so try to follow me. Imagine that the gear shown is the forward gear ( it is not, it is reverse, but that does not matter. They are both very similar.) Also imagine that the left side of the shaft goes through the hole in the gear and both are toward the front of the gearcase. The photo of the shaft shows the dog clutch pushed to the reverse p[osition.

The drive dogs on the gears and clutch are tapered on the back or trailing side to make engagement a bit easier. When the engine is running, the forward gear spins clockwise and when put in forward gear, the drive dogs engage the front of the dogs on the clutch, spinning the prop shaft clockwise.

Now, you must also picture this: When you put the stopped engine in forward gear and spin the prop in the correct direction, clockwise, because you are spinning the prop shaft by hand the trailing edges of the drive dogs are in engagement. If you do not have enough movement of the linkage or if it is adjusted so that it does not fully engage the drive dogs under power, then when you spin the prop by hand with the engine in forward gear, the drive dog trailing edges will "ramp" up over each other and drop back down with a clicking noise as you spin. This indicates that you do NOT have positive engagement. Positive engagement means that the drive dogs are seated on each other all the way so they will not pop out of engagement under full power.

Although this is a useless gear and shaft, you can still see the drive dogs and tapered trailing portions I have described. You can also see that it only takes about 1/4 inch of movement in either direction to positively engage the drive dogs.

Whether on muffs or in the water, you should hear a clunk when engaging gears, however, it should not be excessively loud--this would indicate that the idle speed is too high.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Okay that sheds some light on things. I will give it a try again tomorrow. Right now I am having a hard time with the coupler and rod. Mainly once I get the rod in the coupler hole it makes it very hard to turn the rod to adjust. When I first put the lower back on I was able to turn the rod much easier, now no matter what I do the coupler makes the rod really hard to turn to the point where I have to use pliers to turn it. I am starting to think I have maybe bent the rod a little or something. Since I have two peice rod I am supposed to back out 4 turns but this is not high enough to line up with the hole for the pin so then I pull up just a little to get it lined up so pin will fit and this puts it into gear. Maybe I am doing somehting wrong here?
 

foodfisher

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Should be the same as an '86, so there is push/pull adjustment in the motor cowling where the rod comes thru the pan. It appears turning the coupler changes that adjustment also.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

The coupler only goes forward or back on the rod that comes out of the leg, it slides and is not a threaded set up. So turning the coupler would only turn the coupler and keep it in the same position. Sliding the coupler forward functions as to have the shift rod line up with one of the holes on the coupler. Then on the shift rod and coupler there is another hole and these have to be lined up in order to get the pin in which holds the shift rod in place with the coupler. So I am not sure this is the same set up here is picture of my set up DSCN7952.jpg
 
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Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Frank, I tryed again today. Here is what is confusing me some and this is how I left it, with the shifter in reverse I turned the prop counterclockwise and it locked then I also turned it clockwise and it locked also, what does this mean? So now with that said, I put the shifter back into neutral and turn the prop in both directions and there is clicking which I know this not right either. If I put shifter into forward and turn clockwise it does not lock, would it need to be like reverse where it locks in both directions? Should I screw the rod down or up to get it to engage in forward? Also, you had asked if I had the model that has rubber bellows as shift rod seal and that is what I have.
 

Frank Acampora

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

The clicking sound would indicate that you are biased too much toward reverse. Since forward is in the down direction, you need to lengthen the shift rod to get more forward travel and reset the neutral position. Now as you can see from the above photos, there is not a lot of travel in the whole shift system.

Thus: you would screw out or up the shift rod a half turn at a time until you get correct shifting, then stop. You do want the forward gear to lock up in both directions when the prop is turned by hand. Then bias it just another 1/2 turn to ensure full engagement.
You should understand by looking at the photos, that as you change the setting of the shift rod it affects all three gear positions: Forward, neutral, and reverse. Thus, going too far in one direction will affect the engagement of the other gear and neutral. Additionally, going too far in either direction will put excessive loads on the brass shift saddle which rides in the groove of the shaft that moves the drive dog clutch (not shown in the photos). Thus, similar to Goldilocks, too much one way is no good, too much the other way is no good, but this setting is just right. Under the best conditions You want it to not make noise in neutral, yet lock up in each gear when the prop is turned by hand the wrong direction with the engine in that gear. Usually this is attainable.
However: Since reverse usually is used at lower power settings it is not as critical, so if it does not lock up in both directions you do not need to be overly concerned.

The reason that the rubber bellows model requires the shift rod to be unscrewed 4 turns to start is that if the shift rod is screwed all the way in, the heavy rubber bellows will compress all the way before full forward gear engagement is acheived and the engine will pop out of gear when running. Crappy design by Mercury, if you ask me. They could have done better.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Thanks so much Frank that helps me so much and clears up alot of things for me. I would have to agree with you on the bad design with having the bellows. That brings me to another question that kinda threw me off. When I first opened the lower the rubber bellows had a cable tie attached to it around one of the ribs. Originally I thought that someone had just put it on there to for a cheap fix, but while searching lots of posts someone else had the same design as me pictured and it had this on theirs too. Which made me think that maybe that was part of the original design. Do you know if it is reallly supposed to be there? I did cut this cable tie off and replaced with new one but I was not able to find one that was as small as one I cut off. Could this possibly cause a problem? I have included a photo so you can see what I am talking about it was taken before I cut the original off.
shift rod bellows.jpg
 

Frank Acampora

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

The cable tie is absolutely necessary. It is not in a space between the bulges of the bellows. Rather, it is in a groove around the top of the bellows. It not only seals the bellows to the shift rod but also locates it in a wide shallow groove in the rod. So, after locating the rod in the bellows then screwing out your four turns, tighten the cable tie snugly. The shift rod will still turn, but with difficulty. Again--crappy design. Before I worked on one, I thought it was a good idea but actually setting one changed my mind.
 

Karla45

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Re: Cannot get boat to go into forward or reverse after put lower unit back on

Well I am pretty sure when I put things back together that I did not do the four turns first before I put the cable tie back on. This is really good information thank you so much.
 
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