F head fouling plugs quickly

There are different needle valve seats available for the YF. If the seat orifice is too large, and the pump pressure is a bit high, fuel can be forced past the valve. This will cause the fuel level to be too high in the bowl, which will make the carb run rich.

Since the carb was recently rebuilt, it's possible the wrong seat was installed at that time.

I don't recall the correct size, but a search should give you this information.

 

Nope choke is fine. I think game plan will be put clean oil bath filter back on. Ensure the timing is set right and then investigate carb. In that order
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I know that when I got my f-head powered jeep it had a stumble at idle that just wouldn't die, which led to fouled plugs as I continued to tinker with things, (I went through three or four sets in a couple weeks actually). After replacing the entire ignition system it was still there, (by the way, using a feeler gauge to set the points is pretty effective, just keep in mind that depending on which point set you get/which distributor you have, you may need to "modify" the point assembly to get it to adjust right). Also, if you don't have access to a timing light, do a search for "static timing f head" or something like that, there are some pretty accurate methods to get it right.....and finally: The plug issues and uneven idle only disappeared when I rebuilt the carb, "Brian P" has a wealth of knowledge on the Carter YF carb, and was the only reason that I managed to pull through mine, (watch for vacuum leaks when you put the carb back on by the way). Another thing that did help along the way though was bypassing the balast resistor. If you coil is the internal resistor type and the balast resistor on the firewall is going bad it will cause some ignition problems, this was another contributing factor to my issue as well.

 

"If your coil is the internal resistor type and the balast resistor on the firewall is going bad it will cause some ignition problems"

You dont use both. Internal resistor means (no ballast) resistor is to be used in conjunction with.

 

" You dont use both. Internal resistor means (no ballast) resistor is to be used in conjunction with."

thats what I was saying. Though some jeeps, i.e. mine, came with an internal resistor coil and a balast resistor still hooked up. In some cases the balast resistor will not cause problems with an internal resistor coil, unless the balast resistor is going bad. At least in my experience.

 

My F-head was fouling plugs VERY badly when I got it.

If the plugs are fouling black/wet, then try this:

Disconneced the stock PCV and plugged it off at the intake manifold and my engine runs so clean it's not even funny anymore. My engine was sucking a tremendous amount of oil up through the stock PCV that it was consuming unbelieveable amounts of oil, as well as fouling the plugs in record time as well.

The filler neck has a 1/2" breather port on it anyway so crank case pressure is not an issue, the PCV valve IMHO is unneeded. My F-head runs SO much better than it ever has and oil consumption has drastically decreased.

Something to 'try' and see if it helps. NAPA sells a the correct threaded plug to block off the PCV line at the intake manifold. $2 fix for me.

If it's a very dry black fouling, the it's fuel.

 

Thabks for thw responses, I have bot had time to get back to it yet but I will let you guys kbow how it goes
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Ok, clean the snot out of the oil bath filter with kero and an air gun, but i still think there is stuff in there, but it is much much cleaner with new oil to boot. So we have clean oil bath filter, new cap, new rotor, new plugs(again). Still the same thing, sooty plugs (a little bit wet but not bad at all). motor runs very smooth but there is a "miss" coming from the exhaust. 60 psi on the oil gauge at idle. I still think the idle is a little high and I ordered a dwell meter that will be here tomorrow. I am uploading a video now to you tube (taking forever) you will hear what I am talking about with the "miss". I went to check timing and found that I have no timing mark on the lower pulley or on the timing cover???? I am really confused on this. How am I supposed to check timing, FSM shows there should be one, so now I wonder if something has been changed. Will post vid as soon as it is done loading.

 

here is the video: http://www.youtube.com/watch?v=4Sy5SwnIyn4

And yeah I can tune a carb ok, I am gonna try and lean it up some. I want to mess with the timing some, but with no timing mark and no dwell meter for a tach yet I will wait till it comes in.

 

When you cleaned the oil bath air cleaner did you look between the inner and outer shell under the outside shell intake holes to make sure its not obstructed with caked on crud?

Not trying to :dead horse: but it can be hard to see

 

Brian, i cleaned it the best I could, but I can not see a good way to clean that thing out all the way.I did blast the **** out of those holes with air and kero

 

It sounds like you got it, The dirt build up thats hard to see on neglected units is usually right under the holes in the outside of the filter body.............the ones facing the firewall. The only way to get it out is make a small flat scraper and go fishing.

Listened to video, After you are satisfied with timing if its still blubbering I would bet the Pump Diaphragm is leaking if the rig has sat for any length of time.

Looks like a good rig, all in one piece.

 

My local Napa was a dead end on that diagram part number. Did a search here and plan on ordering a rebuild kit for the whole thing.

 

Sorry to hear that, If its in the budget see if your kit supplier can get an extra pump diaphragm for you to have on hand. Some of the modern fuel blends can be hard on them.

I carry a spare, Had to use it once.

 

good idea thanks

 

thanks billy