Re: Pops out
That is a cone clutch "interim" (prior to the Volvo Joint Venture) drive I believe.....which may put you in "No Mans Land" since they only made that style of drive for about 2 years...
Ensure that it is in fact going all the way into gear.
If it is, then you may have linkage or cone clutch problems. If it's the former, you may be able to make some adjustments.
If it's the latter.....well....It's a drive made by a company that doesn't exist, that is not similar to the earlier dog-clutch drives and if I'm not mistaken, it's not "the same" as the later "Joint Venture" drives either.......which are literally Volvo Penta Sx drives......I'm not even sure you can PUT a Volvo Penta SX on the back of that gimbal......But if you can, that might be your best bet!
If the cone clutch is damaged because the lower shift cable was either out of adjustment or failed, the drive will have to come off. I don't know if you can get one of those rebuilt.
In any case, if you are planning to adjust it, you'll need the correct year OEM manual. Don't even bother with a Seloc or Clymer.
Sorry about that,
Rick