Drive Shaft Binding and dog question? 35 hp super quiet

[raglover]

After tearing down my 35 up gear case post water and owner (me) destruction I put in bearings and gear set from a 33 ski twin.

All the bearings fit and were the same as what came out of the original 58 gearccase.

But the drive shaft seems to be binding. Pinion spins smooth w/o driveshaft in. Inserting the dive shaft is difficult once I get to the pinion and I have to give it some oomph to bottom out in pinion gear.

I can turn the shaft but it just seems tight and like it is really loading the needle bearings.

Possible that the case is bent? Beparings not straight, but it would have to be both of the needle bearings so I am. Little stumped. Defiantly not in a bind until I insert drive shaft to pinion.

In addition to any thoughts on the above is it possible/advisable to run this clutch dog w/o the detention balls? It causes the shift pin hole not to line up exactly….had to put a small chamfer on the pin. Also makes me nervous that when in gear the balls are half exposed from edge of clutch dog, normal?

Thanks for any advice going to battle it again tomorrow.

Allen

[chris-p]

Can you post a pic?

Did you swap whole prop shaft assembly, or just the bearings?

[legendre]

Sounds like a bearing alignment issue.. are you sure the new bearings were driven squarely into the bores? Did you make any effort to centralize them, before you bolted up the case parts?

Have you given the shaft a few good whacks along each axis with the lead or plastic hammer, to see if the bearings will seat properly, or at least yield enough to correct the binding?

[frankr]

It is very possible that the gearcase is bent (or even cracked behind the water bypass plate). In fact, the factory service manual shows how to check for a bent case.

As for the detent balls, that all sounds OK. Yeah, I’ve looked at those half-exposed balls and wondered also. But not to worry, they can’t get out of there. And it is a much better system since they were added.

Your pivot pin mis-alignment sounds like a bent shifter fork, or a shift rod adjustment problem. OR, is it a factory drilled prop shaft, or one that was drilled in the field? If the latter, it may be drilled off-center. It is pretty difficult to get them drilled on center without doing it on a milling machine or an adequate drill press set-up.

[chris-p]

I just realized I can answer my own question, and you must have swapped the whole prop shaft assembly as you stated the prop shaft had the hole with detent springs.

I can remember running into trouble doing this modification as well, although I realized that the shift rod lengths differed. It was only about 1/4", so did not notice it at first, but the lengths do differ. Pay attention to that.

Are the bearing alignment pins in original location? Are they there?

Does the stiffness come when you bolt on the skeg half, or simply by dropping in the prop shaft assembly? You should not have to force it, it should drop in.

I always start at the front, then lower it back down to the aft. Then spin the prop shaft seal housing until the alignment pin drops in the hole.

[raglover]

Thank you for the feedback.

Feel better about detent and balls in prop shaft.

I will get some pics today but to clarify a few points first. The binding comes with the skeg off and only when I drop the drive shaft into the pinion gear. There is no additional resistance in the system. Binding may be a poor word as I can rotate the system but it feels like I am really dragging on the driveshaft bearings.

I also put the bearings in with a driver but the could be off, will check again. I am using the original shift rod but the later model fork so length should be the same. I put a very small chamfer on the end of the pin and got it to go.

Not sure what you mean by field drilled prop shaft bore, assumed they were all milled at the factory? I agree that would be tough at best in the field.

[frankr]

Actually back in the day, OMC came out with service literature telling dealers how to drill and install the ball detents in previous motors. I did them on a drill press and have to tell you they are extremely hard to drill because of work hardening. Much easier now that I have a mill and a little bit of experience drilling stainless steel. Not much, but enough to get into trouble.

[raglover]

Well sorry for the lack of pics but I am now about 90 percent sure I have a bent housing.

1. Reset the bearings…..they are bottomed out. Used propane to heat and a driving bar to seat them until I got the "ping" of bottoming out.
2. Made sure thrust washers were in the correct order per manual
3. Removed upper drive shat seal and bronze bushing, drive shaft glides into the pinion no problem like I would expect
4. Tried to slide bronze bushing in and it will not go without putting some leverage on the upper shaft, not much since I have a fairly big moment arm, and I can push bushing in.
5. Once I do that the drive shaft will not pull out of pinion without a lot of force which is even harder with the light coat of grease all over it now.

I have tried another pinion and drive shaft with the same results.

Do the experts agree? I have heard of this before but never seen it. Is it common? The drive shaft and upper bushing show no really abnormal wear that would indicate it ran like this or if it did it must have worn the lower bearings that were water damaged. I really assume this is not a runnable condition on an otherwise good drive shaft, gear set and power head, correct?

Anything to look for in the donor market to indicate the issue?

Thanks,

Allen

[frankr]

I agree, bent gearcase housing. At least until proven wrong. Wouldn’t be the first time. Run it long enough that way and it will break the drive shaft.

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