Update: I went through the entire machine and cleaned it out. It's looking good so far. Unfortunately the issues with the space bar were still there, but ultimately I decided a quick fix would suffice. It seems that the arm that connects to the spacebar linkage wasn't consistently pushing the "lever" that activates the carriage to move one space. The quick fix was in applying a small bit of sticky tack to the end of the arm bar and so far it engages and pushes correctly every time.

In the meanwhile I'll be searching for a service manual and/or try to find the reason why it started malfunctioning in the first place.  

Hello. I have dug around quite a bit online but I haven't really been able to find a satisfactory answer. I'm having problems with the space bar on my Lettera 36. It's spotty, doesn't respond when I push it about 30% of the time and will occasionally "jump" a double space despite being pushed only once. I've opened the typewriter up and I have been pretty successful in fixing some of the weird things it had going on but this particular issue has me stymied.