trouble removing prop shaft

[danray35e]

So I am rebuilding lower unit on 1976 55 hp Johnson. I am at the point where I am need to remove the pinion gear from the drive shaft. The manual I have shows two different sections for the gear housing. One is for a hydro mechanical gearbox, the other is for a mechanical gearbox. Mine is the mechanical. Instructions for disassembling the two different types are very similar. However in the hydro mechanical it says in order to remove the prop shaft that after I have removed bolts from shift rod housing I should pull up on shift rod with one hand, and pull out on prop shaft with other hand at the same time with enough force to disengage them. The mechanical instructions don't tell you how to remove the shaft at all. It simply goes from removing snap rings to removing pinion gear, yet says to put a socket on the pinion gear nut, which you cant do with the prop shaft in place. So I tried the instructions for hydro mech gear box. I pull up on shift rod and out on prop shaft at same time but that doesn't work. Maybe I'm not doing it forcefully enough, but I don't want to damage the shifting mechanism.

 

[F_R]

Re: trouble removing prop shaft

Well, thanks for jogging my memory bank a bit. It has been a long time since I've been into one of those, and things are getting a bit foggy.

Anyhow, the two systems are very different in that area. Yes, the hydro shift rod and prop shaft have to be removed and reinstalled at the same time....I know that for sure. What I am not so sure of is the other one. What I THINK you have to do is get that pinion gear and drive shaft out of there. To do so, you need to get a wrench (not a socket, obviously) on the pinion nut and rotate the shaft to unscrew it. Then I THINK you have to unscrew and remove the shift rod (may have to push it down first). Then I THINK the prop shaft, clutch dog, and bearing housing all pull out together.

NOW, somebody can tell me if I am THINKING correctly, or am getting old. (I knew that).

 

[Haffiman]

Re: trouble removing prop shaft

F_R, you are mainly correct, but a few tips.
The drive shaft may sometimes be a pain in the 'A' to get off the pinion.
Loosen the pinion nut until flush with the drive shaft and be sure the screws holding the upper bearing housing (under waterpump) are removed.
Push down the shift rod until clutch dog is just under the pinion and place a 'spacer' between the dog and pinion nut. Might be a big flat screw-driver or whatever.
Give the prop-shaft a short knock UP, and the pinion will normally drop loose. Remove the nut and pinion, pull up the shaft.
Push the shift-rod all the way down and un-screw and remove.
Pull out the prop-shaft complete with shift housing.

 

[danray35e]

Re: trouble removing prop shaft

any idea what size wrench is needed? I thought it was 3/4" but when i tried it just slipped off

 

[boobie]

Re: trouble removing prop shaft

Try 5/8 " or 11/16 ".

 

[danray35e]

Re: trouble removing prop shaft

It turned out to be 11/16. It came loose and I was able to pull the drive shaft free. The prop shaft is still in there. I pushed the shift rod all the way down and removed it. but the prop shaft is still not coming out. It is loose but obviously attached to something. One manual I read says that sometimes the shaft housing will get stuck, and to use a 2x4 with a hole drilled in it, then tighten nut down on prop shaft over 2x4 to break it free. I hope its not wrong.

 

[danray35e]

Re: trouble removing prop shaft

Turns out I did not need the 2x4. I just gave a quick yank, and the whole thing came out as one assy. I am well pleased with what I found inside. I took it apart in the first place because i found what appeared to be water, and grey sludge when I drained it. After examining all the gears, and parts they all look to be in excellent shape. So I have all the seals coming. Now to clean it all up and put it back together.