f-head misfire at idle......still

I have had two different sets during this ordeal.
set #1. that I started with (and have since put back in) are autolite 306 I think....
set#2. are autolite 295.
I have only had the oil fouling show up that one time.....not a hint of it since.....

I have cleaned them with carb cleaner, till I ran out, then denatured alchohol.....

By the way.....I was just reading more on the ballast resistor.....since I put the coil in that says to use without a resistor, can I just bypass the resistor to eliminate that as a possible problem, and run it that way?

 

Ok, the 295 and the 306 look to be equivalent except for the 306 being a resistor plug. You could also use a Champion 871 (old number RJ8C). A Champion 592 is equivalent to the old RJ12C and would be somewhat hotter than the plugs you have now.

 

how about the bypassing of the ballast resistor, good or bad idea?

 

I thought you bought a coil that said to use with a resistor. You don't need a ballast resistor with a coil that says it should be used without a resistor.

There are two kinds of coil - those used with a ballast resistor and those used without a ballast resistor. Without means you wire the ignition directly to the coil, and the resistance is internal to the coil.

 

I checked the spark on the new coil,(required resistor) and it was the same as the old one,(non resistor) plus after I installed the new coil, and newest plugs, the jeep ran worse, got hot, etc.....
its better now with the old coil....I'm returning the one I got to replace it....I did clean alot of corrosion off the original coil though.

 

Coil shouldn't affect overheating ... I can't think of how it would.

If the coil says you can use it without a resistor, then you can. I don't think it will make any difference though. The spark voltage will be reduced some when you add more resistance - very likely not significant IMO.

A lean condition can also make the engine overheat.

Wait wait. You say the spark is the same - yellow or orange? It should be blueish-purple (ionizing nitrogen in the air - snap snap snap... ). If they both give an orange or yellow spark, then you have a different problem.

Expect that you can't return electrical parts - I'll be surprised if the store takes the coil back.

 

Remembering back in days of my youth, coils were 6 volt. When the 12v system came along, the coil manufacturers made the 6v coil with internal resistor (so labled) and used them in 12v systems, dropping the 12v down to the 6v range to keep from burning up the coil. If you use the ballast resistor in conjunction with a coil with internal resistor you will end up with weak spark.

 

Go without the resitor.
Plugs = Champion J8C (found mine at Home Depot in the lawn mower section)
Carb mixture screw at 1 to 1 1/2 turns out from lightly touching bottom.
Idle set around 900 (mine seems to like that better than anything lower - books say 650 or so)
Timing at 5º
Points at .020
plugs gapped to .030
How is the air cleaner element?

 

I'll try to return it....
The spark is orange,(right out of the coil wire) but has a blue tip where it contacts the ground....same on both....shocked the crap out of me too....seemed pretty strong in that respect....

 

I haven't cleaned the air filter yet.....trying to find a good way to do that.....I did put fresh oil in the oil bowl though.....It does however run the same through the filter as it does without it....
What are the drawbacks to idling that high? anything besides lower gas mileage?

 

Run a 12V wire directly to the coil (remove the usual wire from the ballast resistor) and see what the spark color is.

 

any easy way to do that without someone else to crank the starter.....My wife is at work right now....

 

I wasn't suggesting that you use a vacuum gauge to check for leaks, but to use it as the wonderful diagnosing tool that it is. Check any repair manual or website and you'll find ~a dozen possible symptoms that can be gleened from the gauge.

I agree w/ Tim to leave the timing alone for now at 5°, but note that RETARDED timing is a cause of overheating too.

 

Jump the solenoid

 

What would you recommend I do that with to prevent electrocuting myself....I'm very good at electrocuting myself...(ever get an oil filter wedged between the starter terminal and the engine block? I don't recommend it.)

 

Rubber Gloves?R)
hooking up a remote starter switch would do it..

And try these guys for the Pertronix unit. http://www.vintageperformance.com/retrorockets/

 

Umm, you're just providing a little power to the little terminal on the solenoid so that it can do it's job of sending big power to the starter.
As said, remote starter is nice to have. One could be cobbled up quite easily.

 

Actually...good news....I went ahead and bypassed the ballast resistor, started it, waited for it to warm up.....fiddled with the carb adjustments, and......

Now I have it idling smooth at around 700-750(my tach only shows intervals of 100) rpm....its a little shaky, (I probably should replace the motor mounts one of these days...)but otherwise, most of the misfire is gone,(just a tiny skip every now and then) and I can disconnect the #4 plug wire and rpm drops......I appear to have a four cylinder again.....Hasn't shown any signs of overheating while I've had it idling either.....It may have been the resistor all along.....(The only thing I can figure out for why it got hot is that maybe I had it running too lean. Now I probably have it running too rich, but it seems happy, just smells a little like gas.)

 

Congrats!!! Glad the machine is back on the road!

Check this Tech Section post. I thought a ballast worked or it didn't but this info states it can cause the probs you had. Also note that you may experience points burning without some resistor.

 

Thanks man......drove to work today, and its doing better than it ever has....I even kept up with traffic accelerating to 35.....Thanks to everyone else as well, for all the help/putting up with this long drawn out process.....