lower unit shift lever lower unit from another motor

Alright, We recently were given a 1977 Johnson 70 hp. with out a lower unit. So the search began, I found another motor in another neighboring state that was supposed to be a 1977 as well. I bought the entire motor with L unit and prop. They both were a four spline. I checked the impeller and changed the lower unit fluid. It matched up great and after a little work got it o seat. I connected the shift lever and now it seems the shifter is hard to get into gear and does not seem to be shifting into gear properly. With the shifter in the upright position, the prop will not turn freely and is in gear. After reading a few post on here it seems that we either have a lower unit from another year, or the shift rod got turned. The rod comes thru the bottom of the cowling fine and when turned the correct way fits into the coupler at end of the shift lever.
The motor we have does not have any id on the manifold section, transom mount or freeze plug. The replacement motor says it is a 76 on the id tag but on the sticker on the engine it says "1977 17 degrees" but the lower unit fits fine. Just an FYI the lower unit when bolted up all 5 bolts go in fine but the tear drop or back end of the lower unit is off a little to one side by about 1/8 inch. maybe different molds?
Also how do you adjust the trim tab on the lower unit?
Incidentally the carbs on these two motors are different. One having and electric choke or injection and the other has carbs with a choke lever that is controlled by the choke spring. Did they use different choke systems and carbs on the same year?

Re: lower unit shift lever lower unit from another motor

Can you adjust the shift cable? You should be able to adjust the trim tab by loosening the bolt in the middle then turn the trim tab to where you want it. Push the tab to the right if your boat steers hard left or push the tab to the left if your boat steers hard to the right. The exact position depends on the size of your boat and the amount of torque the motor has.

Re: lower unit shift lever lower unit from another motor

Old rude dude beat me to it. YEAH, what he said! LOL

Re: lower unit shift lever lower unit from another motor

Thanks for the help on the trim tab. Now on to the biggest problem. That shift rod. Im sure we have turned it a few times. Any help is much appreciated.

Re: lower unit shift lever lower unit from another motor

I will give this a shot. I wonder if you installed the lower unit with both the (lower unit and control box) in forward gear? I have heard that BOTH units should be in forward gear upon installation; however, from personal experience, I have had success with both being in neutral gear as well. It is IMPORTANT that both units match up during installation.

Something between the lower unit and control box is binding. Do the control box cables operate freely without being connected to the motor? Make sure they are free and clear. You should be able to adjust the shift cable with the adjustment screws (where they enter the motor) to free things up a little.

Also, are you sure the lower unit off the purchased motor is going into gear properly? You should be abled to pull and push the shift rod up and down by hand to hit forward-neutral-reverse. If you cant get the unit into gear, you may have found your problem.

Re: lower unit shift lever lower unit from another motor

Thank you for your help so far. The shift did move freely while the lower unit was not installed. It moved up and down quite normal. As far as the shift box and motor matching up during install, the low unit was in neutral and when the shift rod came thru the cowling, I turned it to right so it would line up. I then shifted the shift box so that we could install the thru bolt from the connector to the rod. Then is when we experienced the stiff shifter. The cables are free and did move freely before install. I have not tried anything yet as I wanted to hear from everyone here. I want to get this running tonight if possible.

Re: lower unit shift lever lower unit from another motor

Well, you are gettting it narrowed down. I think you must do some major adjusting to the control box cables where they enter the motor. These look like small finger wheels that tighten or loosen the cable as needed for the perfect adjustment. I would disconnect the throttle cable from the motor to isolate the shift linkage. It sounds like you are very close, but somehow the cables are out of adjustment. If you can spin the prop freely by hand without any noise, then you are in true neutral. Put your control box in locked neutral, and look at your shift rod and cable alignment. Adjust the finger wheels clockwise or counter clockwise until everything lines up.

Good Luck. Keep at it.

Re: lower unit shift lever lower unit from another motor

Thank you TD_Maker for the encouragement. What would recommend we do about spinning the shift lever? Or should we just try the adjustments at the motor first?

Thanks again. Terry

Re: lower unit shift lever lower unit from another motor

I would try adjusting the cables at the motor first; afterall, this is what they are for. As you turn the cable adjuster, you are making the cable longer or shorter to fit the coupler which would fit the shift rod to the lower unit. Does that make sense? Again, put your control box in locked neutral, and make sure your lower unit is in neutral, and turn the cable adjuster in or out until everything matches up.

You seem to be concerned about spinning the shift lever. Did you spin it several times or something? I dont think a small spin of the quarter turn to a half turn would really make that much difference in alignment. This small amount can easily be accounted for with the cable adjustments at the motor. Disconnect the throttle cable from the motor to simplify things a little.