I just bought my first Ram 50 a month ago. It's a 1988 with a 5-speed and the 2.0 L. It's also got the stock Mikuni carb.
It was running fine, and then not--it really started to sound lousy, running rough and hesitating. After a lot of research, I had the problem about 80% diagnosed as a bad bowl vent diaphragm. After DAYS of searching, I was finally able to locate one of these diaphragms over the internet. It's a little rubber ring on about a 3" shaft, and "pops" out of the carb sort of like the axle on a front-wheel-drive car. Anyway...
The new part arrived today, but when I tried installing it, I encountered resistance. Turns out the gasket on the receiving end (DEEP in the carb!) had become unseated, and was rattling around loose--thus, it wasn't grabbing the shaft like it should, and me forcing the shaft in was only making things worse.
It seems like my only options now are to A) take the carb completely apart, hoping to re-seat the gasket, or B) take it to a shop and throw money around. I hate to do the latter, but I've never opened a carb before and I'm not sure I'd be able to get it back together. Help!