MC2100 carb misc tuning questions

[thistle3585]

1. Cleaned and rebuilt the MC2100. Seems to run much smoother but when I attempted to reset the carb screw on the drivers side nothing happened. I turned the passenger's side in, it stumbled and I backed it out a bit. Should I be concerned about this? I think that it is burning a bit rich, based on the exhaust smell. Could this be related?

2. I saw a post and photo on another forum about plugging a hole in the bottom of the carb with epoxy if I'm running a manual choke. Never heard of this before. Any thoughts?

3. I have a port in my carb and in the carb spacer for the PCV. Does it matter which one I use? From outward appearances, it doesn't seem to matter so I used the spacer port and plugged the other.

4. I also have a port in the spacer for the distributor advance. Is that correct or should I use the one under the choke?

 

[Bent]

1. Try swapping the idle mixture screws. The port or the screw may be warn out. If the problem follows to the other side, replace the screws. If not just run it all the way in and then back it out 1 1/2 turns and drive it.

2. The hole that needs to be plugged if you are running a manual choke is on the side of the carb near one of the screw holes that hold the choke thermostat housing to the main body. The port then runs down to the carb base as shown in your picture. The port draws hot air up through the hot air tube and into the choke thermostat housing to heat the spring on the auto choke set-up. If it was a factory manual choke, that port may not be drilled. I would epoxy it at the choke mount location and not on the carb base.

3. I had to use the port on the spacer, my carb has no pcv port. I would probably still use the spacer port so that oily junk isn't going into my carb.

4. Use the port under the choke for the vacuum advance. That is the port that will have no vacuum with the throttle closed.

Good luck