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OMC COBRA TKO horrible noise

The forks just slip into slots if I remember correctly. 13 rides in the spool 7 and as an assembly it all stays in place. Biggest thing I remember is that pin 18 indexes into gear housing at 6:00 position so nothing can try to rotate.
Put grease on the lever & cradle to hold them together while assembling.
 
The forks just slip into slots if I remember correctly. 13 rides in the spool 7 and as an assembly it all stays in place. Biggest thing I remember is that pin 18 indexes into gear housing at 6:00 position so nothing can try to rotate.
Put grease on the lever & cradle to hold them together while assembling.
Thanks i really appreciate the info, im still in the process of cleaning everything up. Im thinking of taking both halves to a machine shop and having them dip them in a hot tank to clean them really good cause there is a lot of metal shavings and stuff and i want everything to be nice and clean when i assemble it all. Again thanks for the info!
 
Just looking at the drawing, it looks like the long rod #47 is the top of the mechanical shift mechanism, and extends down through the drive and it may connect to #15 which pivots on pin #21, and 13 and 14 are inside that #16 housing and maybe pushes or pulls pin #7 in the opposite direction for reverse?
Not sure - just a shot.
Use a magnet to collect shavings and a pressurized water hose to blow out the main unit..
 
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well i took the lower end to the only omc dealer in town to get rebuild cause i was told the gears have to be set with special tools. mechanic has had it for about 6 months now and is just now working on it but is having an issue with the pinion gear sitting to high and when he put the pinion gear housing on the propeller shaft wont turn freely. so i dont know whats going on with it. does any one know what could be the issue as to why this is happening? he set the pinion bearing with the tools the book calls for but its still not working. the other gears are supposedly set by the book so i dont know why the pinion gear is too high and not allowing the housing to be torqued to the specified number and allowing the propeller shaft to turn. and help would be greatly appreciated thanks
 
The nut has to be removed to get the pinion gear out, and the forward gear, if needed. It is held on the shaft with a spline connection and will fall out when you pull the shaft up through the top. You will also need a new nut, as they are designed to just be torqued once and then throw away.
It took me two weeks to get the right set-up to get that nut off. My nut was 1 1/8 inch, and I bought a socket, and I sliced about a quarter to a third of it off, right down top to bottom, so it wouldn't bind on the back forward gear, and used a breaker bar, which was small enough to fit in there, and it would still slip off. I bought another socket and cut off enough to leave 6 of the eight corners, about a quarter of it off. If you slice off a socket, set it up so you are slicing it in the right place to have enough movement, and use an angle grinder with an1/16th inch carbundium cut-off blade. Oh, I used something to wedge the bottom of the breaker bar up, so that it would not slip off, I think I just pounded in a long hardwood wedge to hold it up against the nut. You have to invent tools when working on these older drives. Oh, you also need to hold the shaft at the top, and you need a special spline nut, available on this website, I believe. You can just hold it on the bottom with it all locked-in and turn it from the top with a large rachet or torque wrench. That is how it finally came loose. My nut got rounded off from earlier attempts and there was hardly anything left of it. It may work with an open-end wrench on the bottom if it is small enough and you have some means of wedging it up hard enough to hold, when you turn it from the top.
 
The nut has to be removed to get the pinion gear out, and the forward gear, if needed. It is held on the shaft with a spline connection and will fall out when you pull the shaft up through the top. You will also need a new nut, as they are designed to just be torqued once and then throw away.
It took me two weeks to get the right set-up to get that nut off. My nut was 1 1/8 inch, and I bought a socket, and I sliced about a quarter to a third of it off, right down top to bottom, so it wouldn't bind on the back forward gear, and used a breaker bar, which was small enough to fit in there, and it would still slip off. I bought another socket and cut off enough to leave 6 of the eight corners, about a quarter of it off. If you slice off a socket, set it up so you are slicing it in the right place to have enough movement, and use an angle grinder with an1/16th inch carbundium cut-off blade. Oh, I used something to wedge the bottom of the breaker bar up, so that it would not slip off, I think I just pounded in a long hardwood wedge to hold it up against the nut. You have to invent tools when working on these older drives. Oh, you also need to hold the shaft at the top, and you need a special spline nut, available on this website, I believe. You can just hold it on the bottom with it all locked-in and turn it from the top with a large rachet or torque wrench. That is how it finally came loose. My nut got rounded off from earlier attempts and there was hardly anything left of it. It may work with an open-end wrench on the bottom if it is small enough and you have some means of wedging it up hard enough to hold, when you turn it from the top.
It Turns out it looking like the mechanic put the drive shaft bearing on the wrong way. Monday he is going to take it apart again and make sure the bearing is on the correct way. Hopefully thats what is causing the pinion gear to sit too high.
 
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