'63 650 pinion gear removal

[shoestring]

tearin' into my kids 650's LU. all forward, no neutral, no reverse. dropped the lu and the shift shaft just spins. motor starts and runs like a top so i decided to tear into the lu to fix the shifting problem, replace the seals and give the lu a general good bill of health. prop shaft hub is out, upper drive shaft bearing retaining screw is out. pinion nut is out, i'll be darned if i can get the pinion gear off of the drive shaft. what have i missed here?

 

[daveswaves]

Re: '63 650 pinion gear removal

tearin' into my kids 650's LU. all forward, no neutral, no reverse. dropped the lu and the shift shaft just spins. motor starts and runs like a top so i decided to tear into the lu to fix the shifting problem, replace the seals and give the lu a general good bill of health. prop shaft hub is out, upper drive shaft bearing retaining screw is out. pinion nut is out, i'll be darned if i can get the pinion gear off of the drive shaft. what have i missed here?

Does not sound like you missed anything, except that pinion gear has been on there a long time. Your shift problem is likely the clutch dog spring which is inside the propshaft. You probably don,t need to take the pinion gear off, unless it is worn. You can stick a wooden dowel through the gear that is still in the lower end and see if you can feel the shift shaft lobe push it in and out when you turn it. If it does then there is nothing wrong with the shift shaft.
If you find you do have to take the gear out then the pinion obviously has to come off. I assume the water pump housing is completely removed, exposing the upper drive shaft bearing. Without looking at a parts diagram I can,t remember if there is a locking ring holding the bearing in or just the retaining screw. You should be able to move the drive shaft up and down and feel the pinion gear holding it back.

 

[shoestring]

Re: '63 650 pinion gear removal

Does not sound like you missed anything, except that pinion gear has been on there a long time. Your shift problem is likely the clutch dog spring which is inside the propshaft. You probably don,t need to take the pinion gear off, unless it is worn. You can stick a wooden dowel through the gear that is still in the lower end and see if you can feel the shift shaft lobe push it in and out when you turn it. If it does then there is nothing wrong with the shift shaft.
If you find you do have to take the gear out then the pinion obviously has to come off. I assume the water pump housing is completely removed, exposing the upper drive shaft bearing. Without looking at a parts diagram I can,t remember if there is a locking ring holding the bearing in or just the retaining screw. You should be able to move the drive shaft up and down and feel the pinion gear holding it back.

yes i have the water pump housing off, along with the bearing retainer that is under it. i removed the snap ring off of the drive shaft that is above the upper bearing so the drive shaft would slide down a little. this gives me a little slop to pull the shaft up with a little inertia and "tap" the pinion against the housing. i haven't been into the lu of a merc so i'm not sure what happens behind the foreward gear. the clutch dog spring is strong. the short rod that goes into the end of the prop shaft that pushes the clutch into neutral and reverse came out with the prop shaft. it is hard to see thru the needle bearing in the foreward gear to see what has gone wrong in there. i want to pull the pinion gear so i can get the foreward gear out and understand the goin's on in there.

 

[daveswaves]

Re: '63 650 pinion gear removal

yes i have the water pump housing off, along with the bearing retainer that is under it. i removed the snap ring off of the drive shaft that is above the upper bearing so the drive shaft would slide down a little. this gives me a little slop to pull the shaft up with a little inertia and "tap" the pinion against the housing. i haven't been into the lu of a merc so i'm not sure what happens behind the foreward gear. the clutch dog spring is strong. the short rod that goes into the end of the prop shaft that pushes the clutch into neutral and reverse came out with the prop shaft. it is hard to see thru the needle bearing in the foreward gear to see what has gone wrong in there. i want to pull the pinion gear so i can get the foreward gear out and understand the goin's on in there.

Yup, I got that. The reason I suggested you stick a dowel thru the needle bearing in the forward gear is so that you can feel if the shift shaft excentric is able to push the dowel in and out. If it can it should be able to push the pin in the end of the propshaft in and out and move the clutch dog. I was just trying to have you avoid having to take the pinion off if you did not have to. They can be finicky to get back on. You are on the right track with the inertia and tapping the pinion against the housing. I just wanted to make sure everything was out of the way before you did that.
If it does have to come off you are going to have to find a way to apply more inertia to the problem. like a slide hammer set up. Since there is nothing on the driveshaft to "hammer" against you would have to attach something without damaging the drive shaft. How you do that is up to you. Vice grips will not work they will just slide up the shaft. A 2 piece collar that you can bolt around the shaft for the slide hammer (or piece of pipe) to hit against has worked for me in the past. Bear in mind the parts you are playing with are no longer available.

The pin in the end of the drive shaft should be spring loaded and you should be able to move the clutch dog back and forth by pushing in the pin. If you can.t you have found your problem.

 

[shoestring]

Re: '63 650 pinion gear removal

Yup, I got that. The reason I suggested you stick a dowel thru the needle bearing in the forward gear is so that you can feel if the shift shaft excentric is able to push the dowel in and out. If it can it should be able to push the pin in the end of the propshaft in and out and move the clutch dog. I was just trying to have you avoid having to take the pinion off if you did not have to. They can be finicky to get back on. You are on the right track with the inertia and tapping the pinion against the housing. I just wanted to make sure everything was out of the way before you did that.
If it does have to come off you are going to have to find a way to apply more inertia to the problem. like a slide hammer set up. Since there is nothing on the driveshaft to "hammer" against you would have to attach something without damaging the drive shaft. How you do that is up to you. Vice grips will not work they will just slide up the shaft. A 2 piece collar that you can bolt around the shaft for the slide hammer (or piece of pipe) to hit against has worked for me in the past. Bear in mind the parts you are playing with are no longer available.

The pin in the end of the drive shaft should be spring loaded and you should be able to move the clutch dog back and forth by pushing in the pin. If you can.t you have found your problem.

ok, got the pinion off, removed the foreward gear and found the cam laying in the bottom off of the housing. i just don't know which way the shift shaft turns. if it is in forward and you want to go to reverse does the shift shaft turn cw or ccw to get to reverse looking at it from the top? the rest of the motor and boat is in another town. brought the lu home to work on it. the clutch dog moves back and forth but the spring is very stiff. does not feel like it is binding.

 

[daveswaves]

Re: '63 650 pinion gear removal

Good, glad you were able to get the pinion off. Looking down from the top of the shift shaft the cam should point to 4 o clock. The shaft will rotate clockwise to move the clutch dog from the forward gear, through neutral and then reverse.

 

[shoestring]

Re: '63 650 pinion gear removal

Good, glad you were able to get the pinion off. Looking down from the top of the shift shaft the cam should point to 4 o clock. The shaft will rotate clockwise to move the clutch dog from the forward gear, through neutral and then reverse.

great, thanks a million. this is my kids first boat, '59 larson i think, 14 foot. he got it heap cheap. gonna be cool seein' a teenager cruisin' in a classic like this. impeller was missing 2 fins, wonder where they went? get it back together, replace some fuel lines, give the charging circuit a test and it's of to the lake for a test run. i'm thinking someone pulled the shift shaft out and put it back in and it didn't line up with the cam. sold it cheap to a dumb kid. under $100 for a lu seal kit and new impeller and he should be back in business.