F-head Carb tuning questions

My father in law just picked up a 195x cj5 with the f-head. I took a look at it tonight and found a huge vacuum leak in the form of an open ended hose from the intake. I plugged said hole and the motor crapped out. Wouldn't run with the hose plugged (ran mint before with the leak)

I plugged the hole, turned the idle stop in a bit to raise the idle enough to keep it running. It would run on its own at this point, but ran rough and smoked. I then tried what I thought would be the low speed/idle mixture fuel trim whatever the heck its called screw on the base of the carb. I adjusted both ways (in and out) from seated to 3-4 turns out with no discernable difference. Still ran rough and still smoked a bit.

Open the vacuum leak back up and it runs great.


I guess I am looking for a tutorial on how to tune it. I have done the other two flatties I own, but its a different carb (L head motors)

Is there something else I need to adjust?

Thanks guys!

 

Could said hole be where the PCV line should be attached at the intake/head? That would explain why the motor likes to have the hole open.

 

First thing to do is work out which carb it has on it. Most came with a Carter but they can have several nowdays since the replacement carbs vary. A lot of them have Solex on them

 

It comes from the PCV hole, but has no PCV in its place

It is not a solex carb. Appears to be an original carter

 

My quick guess is that it is running way rich.

This could be a float adjustment or float valve problem, or a leaking acceleration-pump diaphragm etc.

On Carter YFs I have had good luck with (a) simply cleaning, or (b) a basic rebuild kit, unless the throttle plate shaft has worn way loose.

 

I have the same set-up and a similar problem (not quite as extreme). I noticed that at idle there is quite a bit of fuel coming out of the main nozzle (high speed circuit). I did take the carb apart. Not having any parts available at the time, I just did some cleaning and checked the operation. I noticed that the metering rod and jet seem to be worn. Does anyone know if there are parts available that wouldn't be in a standard re-build kit? Possibly the same problem mentioned above.