1984 penta outdrive

Question
I have a 1984 Bayliner with a volvo penta outdrive and a 2.1 liter engine.  I had no forward or reverse and after troubleshooting I got down to removing the lower unit.  I found the problem(what I believe is the problem) to be the spline sleeve between the vertical shaft on the lower unit and the output of the upper unit.  My question is; how does that spline sleeve stay in place?  When I removed the lower unit the spline sleeve was sitting on the bottom of the vertical shaft in the lower unit (therefore there was no connection between the upper unit and the  lower unit).  Evidently, the spline sleeve connects the vertical shaft of the lower unit to the output of the upper unit.  How do I keep that spline in place?  Thanks

Answer
Hi Joe...Sorry for the delay in responding to your question.

Although I'm not a mechanic (available via AllExperts), it sounds to me as if the pinion gear may be the problem. Best you consult a qualified and reliable source to trouble-shoot and resolve.

Safe Boating
Ron