Alignment

well if your not skilled enough to ring the taper then torque it down some more off centered so that you interduce a side load, but then maybe you don't understand simply physics and force diagrams. And I all so guess they are not smart enough to know how to position the wrench so that the prop doesn't spin either, so if your too damn dumb to know either of those then by all means screw it up with the impact.

saffer wrote: At last i have seperated the coupling. She is way off!! about 1cm to port!! You refere a lot to "propping up the shaft", what is your point of referance? Also, is there a bearing in the stuffing box, if not i assume that goes where the shaft goes eh? Thanks

The reference to propping up the shaft is to take the weight of the foreward end off it to keep it from dropping down. You can use a wood "V" block clamped in a way that you can adjust it. I recommend taking any side loading of the stuffing box off by removing the small section of rubber hose and moving it slightly forward. What you want to try to do, is see how concentric the shaft is to the bore in the rubber cutlass bearing/strut. This will be by feeling how easy the shaft rotates. The easier it turns, the better. When you get the shaft to that point, you will then align the engine to it. Side to side and up and down is a visual to make sure the shaft doesn't move when you put the coupling halves together.

A lazer sure would be nice but I don't know of a set up that would work. They are used on shafts but not in such a confined space.

There isn't a bearing in the shaft log/stuffing box. Once you slide the stuffing box forward you will see.

Since the alignment was off quite a bit, you will want to make sure that the prop shaft OD and it's couplings ID hasn't fretted (worn) and is still tight. Keep in mind that this is a press fit and if worn, can't be fixed by just tightening up the set screws. Hopefully the trans will be OK.

8122pbrainard wrote: Since the alignment was off quite a bit, you will want to make sure that the prop shaft OD and it's couplings ID hasn't fretted (worn) and is still tight. Keep in mind that this is a press fit and if worn, can't be fixed by just tightening up the set screws. Hopefully the trans will be OK.

How is the coupling pressed onto the shaft? I would imagine on a bench but then how does it get in the boat...

Hollywood wrote: 8122pbrainard wrote: Since the alignment was off quite a bit, you will want to make sure that the prop shaft OD and it's couplings ID hasn't fretted (worn) and is still tight. Keep in mind that this is a press fit and if worn, can't be fixed by just tightening up the set screws. Hopefully the trans will be OK. How is the coupling pressed onto the shaft? I would imagine on a bench but then how does it get in the boat...

Bag of ice on the shaft and the coupling goes in the oven at 500 degrees. Then it's a mad dash to slide it on with an oven mitt. If you see an imprint of the coupling face burned into my carpet or upholstery, you'll know what happened when I try this in a couple weeks.

well I never did any of that when I replaced the old one with a new, a lite tap with a brass hammer worked fine, as it's really not a press fit like you think, it's a very tight slip fit actually, .0005" is nothing and if you dig out the drawing's I'm betting there is also that much clearance too built into the tolerance stack-up.

.0005" interferance can almost be done by hand, and since everything was new you didn't need to do any of the stuff you guys suggest. Just my .02 gained from personel expierence and knowledge.

The Following information was taken from a separate thread by Eric Lavine regarding common transmission failures:

These trannys have 4 basic problems
1. water inside causing complete failure, which is not the case here
2. cracked forward drum, wont cause the problem you have
3. ring gear for reverse plantary comes loose and you completely loose reverse
4. reverse return snap ring land breaks and you get drag in nuetral (most likely if cable is in adjustment)
oil changes will not effect breakage, you really have to watch the forward to reverse shifting on these transmissions, make it a habit to shift into nuetral letting the prop stop and then shift into the other range within the means of being safe, remember the prop is spinning one direction and you nuetral skip and it allows the prop to do a complete 180, i know someone is thinking this is a ski boat and you are suppose to do this....this will add many hours to the transmissions life




this is an example of a cracked forward drum out of a PCM trans, this will be found both in the 1:1 and the 1.23:1, in the 1:1 it can crack from to harsh of a shift or mis-alignment, this is probably the most frequent problem these transmissions have, it can be avoided by making sure the boat is in align and shifting at idle allowing the prop to stop turning and then shifting it into the other range, of course if you hit an object with the prop this also likely will happen to the drum. it basically is the weak link in the transmission.



This is a Borg Warner planetary that was installed into a rebuilt transmission and the customer installed the trans into his boat completely overlooking alignment, i gather the boat would have been out .050 or so and he pulled the coupling halves together with the force of the bolts and never paid attention to the alignment. The transmission case was completely grooved at 12:00 o'clock position. all 6 of the planet gears were rounded as you see in the picture



This drum failed due to water contamination, as you can see the top ring area is broken from pressing the drum out of the case, the hook style ring expands into the groove that wears into the case and then is impossible to remove without breaking, if you notice the bottem ring has clearance on the sides due to the water destroying the lubricating qualities of the oils and causing the rings to sieze in the groove in turn rotating in the case