I am the original owner of my 85 FXWG,
Not sure what you mean about no VOES hose, just a switch. It should have a vacuum hose. I ran my stock carb, manifold, all the way until a few months ago. It ran fine, but like others have suggested there are better options. I now run an S&S. If you insist on keeping it original I have my stock carb, intake, and newer rubber compliance fittings sitting in a box. I sold the original air cleaner a short time ago, but it has an S&S air cleaner on it. Let me know if it will help you out. You need to have the clamps on the compliance fittings to the manifold or it will leak.

 

Once you are sure you have no vacuum leaks, or perhaps before you do that, do a leakdown test. This will ensure all is well mechanically with the top end. That along with a compression test can speak volumes about the engine. Most knowledgeable mechanics will do these along with taking a vacuum reading before throwing parts and labor at a job. We all need to do basic diagnostic work first then repairs next. I stress this on all our jobs, that's why we don't get warranty work. It makes me wonder why most shops are willing to do jobs twice when a little diagnostic work would have allowed them to do it once.Hope this helps.
So in closing do the tests above then your mechanic can make an informed decision on what is wrong. This is not a rant chastising anyone, just an educational piece.