My 1978 F-100 302 has a problem at times of not wanting to start. This is the forth time in the last couple months. Seems like after a few days of not being used or after a long period high humitity she loves to crank but no want to start. I've tried the starting fluid in the carb. to no avail. After she sets a while in the good old sun she'll start up. What I would like to do is get a hotter spark. I already have the electronic box and distributor. Do I have the hot coil with this original set up? If not would it be a good idea to add some other type of ignition such as the MSD. I really don't have a clue as to which door to open. In the old days I would say buy a new coil and give that a try but I beleive the hot coils are about fifty bucks. Someone please clue me in.

Bob

 

If the plugs are Okay for gap ,it sounds like a weak spark.
Are all the terminals clean :
Distributor contacts
Di-electric grease on plugs and cap ends & coil connection
Rotor contact


Dennis
Please Don't Ask Me Any Tough Questions As:
"I'm Saving Up MY Memory For When I Develop Alzheimer's"







78 F-150 429CJ C6 ,Silver w/Explorer Pkge
641/2 Mustang,Pre-World's Fair Car #8092
64 Fairlane S/C waiting for a 390-4spd.
68-Mustang.Sunlit Gold 80,000 miles

 

Try new wires, cap and rotor first.

 

[updated:LAST EDITED ON 04-Jan-02 AT 07:24 PM (EST)]You should also check the timing. I have a 302 in my '79 F-150. It should be 6 degrees BTC (before top dead center). Take the dist. cap off, and make sure the stator is lined up with the armature...I believe that is correct. (do this while the degree marker is lined up with the factory marks and stuff) If not, turn your dist cap. I had bad timing. My engine wouldn't start very well while it was warm. I also had a clogged carb spacer going to the EGR valve. Also check with a volt meter, how much power is coming out of the coil. Hope everything works for you.

 

[updated:LAST EDITED ON 04-Jan-02 AT 09:01 PM (EST)] Given your description of the problem, I would suspect a connection problem in the module (bad solder joint, temperature-sensitive component, etc.) or the connectors from the module to the ignition switch and distributor/coil or the pickup coil in the distributor; even a intermittent connection in the coil (doubtful, but possible).

I suggest the next time the problem occurs, you take a digital volt-ohmmeter and check the voltage at the coil during 'crank'. It should be pulsating somewhere between zero and 12 volts, depending on the condition of your battery and starter.

I had a similar problem on my '70 F100; turned out to be a bad connection in the harness between the module and the coil.

If your distributor cap is in good shape, humidity should not be a factor (IMHO). But a slightly cooler temperature (or changes in temperature over time) may be causing the pins in a connector or the connections on the printed circuit board in the module to shrink apart just enough to cause the problem (good ole Mr. Sun will fix this for you, given enough time).

Here's hoping you find it soon, with minimal expense.

Eddie

 

I also vote for the ignition module being bad. They seem to be very sensitive to high humidity conditions.