Small Engines (Lawn Mowers, etc.): Tecumseh 8hp starting and running problem, jacobsen snowblower, new spark

Question
Hi,
I have a jacobsen snowblower with a Tecumseh 8hp 2 stage(m# HM80-155015F). This is our work snowblower and I've never used it before. I noticed that it just sat in the same spot for a long time. Its an older piece of equipment. I beleive from 1979. Anyway...I checked the oil and added gas. I wanted to see if it ran or not so I primed and choked it and it started right up. I had it at idle for a couple of minutes and it ran great. I tried to throttle forward and as I got closer to half throttle it would start to die so i brought it back to idle and it went back to idling great. I cleaned and rebuilt the carb, added a new spark plug (a hotter plug), and cleaned the tank. Still did the samething after that. So then i replaced the points and the condenser. I replaced the points because they looked a little wore. Now the darn thing will barely start with the choke closed and it backfires the whole time when it does run.What the heck is going on!!! I'm sure i timed it right. Now I need to get it running back at idle again where I first started. Help!!
Thankyou,
Kyle

Answer
Hi Kyle,

The back firing is probably due to the ignition timing.  I don't know what the proper point setting is but sudden backfiring is more likely due to that, rather than a valve problem.  Once you get it back to the original slow running problem, try squirting fuel into the carb's intake to see if you can get it to run at a higher speed.  If that helps, then look into the lack of fuel flow.  You may need to re-clean the carb.

Let me know how you make out.
Michael