I barrel running rich-possible causes?

[Jesse37932]

Tomorrow I am going to fill my new gas tank, ran all new lines, filter and fuel pump in my '66. Disassembled, soaked in carb cleaner and rebuilt carb with a kit. I had rust in my filter and think thats what killed the fuel pump, any way, everything has been replaced.

Before I started this most recent task, the 170 engine with a 1 barrel carb was running very rich. Replaced plugs, they did not run much, but they got all blacked up and the truck smoked. What would cause it to run very rich? I am studying the carb adjustment/tuning instructions but wanted to ask the "been there, done that" crowd here what to focus on when tuning the carb.

Compression is 120/low, to 127/hi, not great, but not horrible. Just want to drive around town occassionally. I dont 'think' I have a vacuum leak-most lines are metal and look good.
Any guidance on Running Rich would be greatly appreciated.

 

[phldwsnoc1]

A bloody rich condition usually has to do with too much fuel in the float bowl. Causes for that include a poor seal at the needle/seat, a heavy or improperly adjusted float, or something creating negative pressure in the float bowl. It's entirely possible that your carb overhaul corrected one or more of these conditions.

 

[jckkys]

You should have a manual choke. So is it opening all the way when you push the knob in? Is air cleaner dirty? Is it paper or oil bath? Do you see black smoke from the exhaust? Under what conditions? After ruling out these external causes of an engine running rich, internal carburetor issues are next.

 

[Broncobowsher]

The choke is the first place I would look
Idle mix screw adjusted correctly? (is it really always rich or just always rich at idle?)
High float or leaky needle and seat allowing too much fuel in the bowl.
Clogged air bleed passage in the carb.

With it running can you see fuel dripping off the venturi booster at idle? That is too high of a fuel level in the bowl. The cause of the high level may not be known, but at least narrows it down a little.

 

[jckkys]

Mikes Carburetor made several videos on how to fix or trouble shoot 1100 carbs. On this sight one vidio is specifically about trouble shooting float bowl flooding.

https://www.youtube.com/watch?v=eAirfexkMVY

 

[bmbm]

running rich

I can't say for sure but the original 170 in a 66 may have had an SCV carb and loadamatic dist, or called something like that. They were problematic as I have heard so that could be the problem or part of the problem.
If you join fordsix.com and go to the forum you will find lots of info about getting rid of that system with other components for a bit more performance and a lot better running engine.