Carter YF one barrel. I've rebuilt it and about to pull it off and try it again. What am I doing wrong? Here are the symptoms.

1) Engine doesn't want to idle well below 1,000 RPM. At 1,000 RPM there is an occasional miss, but it is much worse at about 800 RPM. Lots of missing and sputtering.

2) Vacuum advance. The old VA module was bad, stuck a new one on. connected the vacuum to the manifold vacuum BEFORE the carb, the one at -20 at idle and lessens as RPM goes up, which I now believe was wrong. Moved the vacuum connection to the spigot on the carb that says "DIS", the one that reads about 0" at idle and increases vacuum as the rpm increases. Isn't this the correct place to pull the vacuum for the Vac Advance?

3) This thing DRINKS gas. I have tried looking into the carb when it was running and I do not see it just pouring raw gas into the throat. I also don't see any "spurt" from the accelerator pump. Maybe I'm looking in the wrong place.

The big problem today is that whenever I try to accelerate from idle, the engine just DIES. Stops. No backfire or anything spectacular, it just STOPS. Then it is fairly hard to restart.

I know i need to go through the carb again, but is there anything obvious that jumps out to you guys (other than I'm a hack that doesn't know what he's doing -- I already knew that).

 

im having problems with an 86 4.9 yf carb. i think the problem with mine is the metering rod. and i dont know where to find one. mine also puking lots of gas, and not iding worth a crap. The yf arent that great, proabably better of with a 2 barrel motorcraft/autolite.

 

lol. Sounds like my problems. I just installed a Holley reman Carter YFA and have the same problems. I'm just going to get an adapter plate and put on a Weber 2v carb and be done with the POS carter.

 

yes, ive heard good of the webers.

 

I had simular issues with Carter on my '77 300 I6. I rebuilt it, and it ran fine, but was really running rich, and when I tried to turn the fuel/air mixture screw out, it was snapped off inside. I got a new in the box Carter off of a friend, and it ran GREAT, but after 20 minutes, it started to run ruff too.

Went to Napa, and found out it was for a 80-86 300 I6, so I got a rebuild kit, for the original carb was $20, now this one was $38. I felt it was reasonable for a rebuild for setting all those years on a shelf, so I rebuilt it, and it runs like a champ.

I had to make a small metal collar because the air cleaner wouldn't set on there without hanging up the choke lever. One other thing I did was the ICM went bad, and I swapped in a new one, and that made a BIG difference at idle. The old one the snaps on the side of the plug was broken off, and it had an intermittent miss I just couldn't figure out.

My gas mileage went from 10-13, to a solid 19.5, and I bought the carb off of my friend for $60 I believe. No, he doesn't have anymore, it was a skid of stuff he bought in one big lump of one price takes the skid, he really didn't even know what was all on the skid.

So it didn't take long for me to recoop the price of the carb in gas savings. I know I am not really answering your question, but giving you some things to think about, so best of luck, and keep us posted on your findings. I know it gets frustrating at times, but these great old trucks are so worth it when your rollin down the road.

 

Took it apart again. Dirt. The little jet that supplies gas to the throat from the accelerator pump was totally clogged.

 

The fuel you get these days is very hard on the rubber hoses. Little pieces of rubber will come loose and stop up your needle valve. I run three filters to make sure the carb stays clean. One at the tank, one between the fuel pump and the carb and the one that screws into the carb. The one that screws into the carb clogs up the easiest. If you are getting trash in the carb you need to change the carb filter, it must have a hole in the filter material.