Adjusting carburetor (1 Viewer)

[77ToyFJ40]

I recently rebuilt the carburetor on my fj40. It didn't run at all until I rebuilt the carburetor. After putting everything back together it wouldn't run unless the choke was out. I tightened the idle air mixture all the way and screwed it out a half turn at a time each time I tried pushing the choke in to see if it would run without it. After a little while of doing this it started running bad and now won't run no more than a few seconds. What did I do wrong. The carburetor is also missing the idle solenoid the previous owner put a bolt in the place of it.

 

[Pighead]

What did I do wrong.

Whatever it was that you did between it running and not running. You should be able to undo and get it back to running.
When I adjust my carb I use the idle speed screw too and also use timing to get the right idle.

 

[77ToyFJ40]

Whatever it was that you did between it running and not running. You should be able to undo and get it back to running.
When I adjust my carb I use the idle speed screw too and also use timing to get the right idle.

I've adjusted it every which way to try to get it back running. It runs rough now but doesn't cut off could it be getting to much fuel or not enough? Float issue?

 

[devo]

Is the fuel bowl filled properly after cranking?
If not, fuel pump or clogged filter?

 

[Pighead]

could it be getting to much fuel or not enough? Float issue?

Sure, could be either. Easy enough to check with the porthole window.
What's the timing set at?

 

[samatulich]

Why did you NOT replace the Idle Fuel Solenoid? I'd start there.
Also, running with full or partial choke makes me think there's an air leak. Carb base and intake manifold are culprits.
It is not uncommon for cracks to form inside the intake manifold, remove the carb and look.

 

[77mustard40]

You’re dead on arrival without the idle solenoid. Get that replaced and functional and we can go from there.

 

[Pighead]

Why did you NOT replace the Idle Fuel Solenoid? I'd start there.

You’re dead on arrival without the idle solenoid. Get that replaced and functional and we can go from there.

Nope, sorry. You do not need the fuel cutoff solenoid to run. I disabled mine years ago and don't miss it. You do have to disable it in a good way, I'm not sure if replacing it with a bolt is the good way or not.
First, I just cut off the rod in the solenoid and that worked, then I got tired of looking at it and dis-assembled it, filled the hole in the base that the rod went through and put just the base back on. No worries.

 

[samatulich]

@Pighead
Good to know, wasn't aware of this.

 

[mattressking]

Need it technically no, It shuts off fuel flow at ignition off to prevent dieseling/run-on.

Bolt/block off is what you need to keep moving and gasket, it just needs to be short enough not to impede fuel flow.

 

[Malleus]

I'd check the float and make sure it isn't stuck closed. It doesn't take much trash to stop a carb.

Failing that, reset to all adjustments at zero and start, one at a time, to adjust them out until it works. You have to work methodically with it, or you might as well be using harsh language to solve the problem - you'll get the same result wither way.

This assumes, of course, that the carb adjustments are the only change you've made since it was running.

 

[charliemeyer007]

When I do adjustments its like a quarter or one eighth turn then wait a for 30 seconds for it to have an effect before making the next adjustment.
+1 for make sure all the other fuel issues are correct. Clean filter, good flow of clean fresh fuel, proper float level. Timing correct, valve lash proper.

Have you ever used an oxyacetylene torch that some gorrolia cranked on the control knobs - they put a ring in the taper stem that makes it really hard to adjust properly - you might look at your adjusting screws.

I would spray the carb out as best you can with some cleaner - then go back to factory setting and adjust from there.

 

[Grayscale]

You need your idle-cut solenoid, if it is on a '77 2F-type carb. From what I observe, the magnetic charged pin is cutting the fuel-air-mix in a regulated way. There are multiple holes in the perforated tube that will attenuate the fuel-air mix thru this 'circuit.' Removing the solenoid as a whole part, leaves the passage unrestricted, free of the orifices that were designed in to it. The pin and perforated tube are integral.

From what I can tell, the bolt used was a M10 x 1, unlike the F-carb with two screws and a gasket, this one uses a conventional machine screw-thread with a copper crush washer (probably at the corner autostore, but thickness will change where that o-ring on the tip of the solenoid sits, I suppose I could measure one of mine). They sell solenoids, just by themselves for 2F. If you replace it, you will need to perform an idle-speed, and idle-mix adjustment.

IIRC, I used compressed air to blow thru the idle-mix screw hole, after I removed the idle-mix screw during a rebuild. I watched solvent move thru the passage, into the throttle bore, confirming its function. Because this circuit was exposed to PCV gasses, after ignition shut-down, it could be corroded? It could have varnish, or the threads on the delete-bolt could have flaked off galvanized plating. It is important to avoid oil dilution with gasoline, which could occur if the carburetor drewels post-shut-down due to the temperature in the engine compartment. 'Dieseling' is just a symptom, as I run a carb in a different rig that has no cut-off-solenoid.

The electrical circuit, for the solenoid, was in the original harness. On mine it runs on the 'Engine,' circuit and it shares a circuit with the voltage regulator.

Using the choke to keep it running is a bigger issue. I'd start by making sure that every spark plug isn't fouled with carbon or oil (because we know that it ran bad for at least a while). A weak spark will make it so the engine hold an idle a bit better with the idle-speed up, which occurs concurrently with the choke in a somewhat closed-position (pulled-out). Clean the spark plugs with a steel toothbrush, some 220 silicon-carbide, a worn-out small 'flat-head' screwdriver for a scrapper, and steelwool. I rinse them in solvent, or use compressed air. Folding the paper over on itself will fit in the gap between the electrode and grounding strap. Reinstall plugs with a minimal amount of dielectric grease where the rubber boot fits (keeps them from seizing). Then try to see if it runs without the choke.