I need some serious help. After 2 weeks of trying to get my 77 f150 351m started, I still have no fire. I was spraying some carburater cleaner into the carburater when my engine stalled. I didn't try to start it again because I didn't want the radiator fluid getting hot. So when I did try to start it again it wouldn't fire. It just cranks and cranks and cranks. I realized that I accidentally broke the condesor wire on the coil so I replaced it. No start. Replaced the coil. No start. Replaced the ignition module. No start. I used a timing gun and found that I wasn't getting power to the distributer.

I need any and all suggestions as to what to look for. All of the wiring looks ok. It seems that I have power going to the coil but it just won't fire.

Thanks in advance,

Glen

 

Try running a jumper wire from battery positive to the positive side of the coil and see if it will fire up. Don't keep running it this way if it works. Too much voltage for continuous running.

 

GP,
I'll assume you used a test light to check for power at the coil.
No ground at the coil is as bad as no power. Once you've established power at the coil then we can work on the ground.
If you replaced the coil and spark box, then the distributor is next. Did you say you broke the condenser wire? Where is your condenser? That is a part associated with a points system which is not a "duraspark box ignition system"? Please clarify.
The stator pickup in the distributor can go bad and interupt the ground signal for the coil.
KingFisher

 

I think the condensor was probably a noise suppressor actually on the coil.

 

thanks for your replys.

I looked up the part in my shop manuals and it was referred to as a condensor. I've heard someone refer to as a capacitor. I did check the coil wire with a light and it does have power. I checked the positive side of the solenoid and it too had power.

The day before this happened it was running perfect. I friend of mine helped tune the carburator and adjusted the distributor only slightly.


Glen

 

Sounds like something inside the dizzy. Try the timing light on the coil wire.

 

I did that as well, and no light. I even went and tested the timing light on my other truck and it worked fine.

 

All,
There is no signal to the coil to fire(i.e. ground interruption). It is either the spark box or the pickup stator in the distributor.
KingFisher

 

Wow, my truck (1976 F-100 with a 351w) is doing what sounds to be the same thing, only it will run when I put gasoline directly into the carb. I replaced the fuel pump, and the fuel filter, not to mention re-building the carb, but still no pumping or something. I have the gas line thats supposed to go to the tank re-routed to an external 2-gallon can. I'm thinking its the timing, but why would it run when gas is put into the carb? Oh....the frustration! Can anyone help me?

 

76, Are you saying it will not run with the pickup line in the external can?

 

One other little trick is usning a outboard line pump, the sqeeze pump in the fuel line from your external fuel can.

You better look in that Carb and see why your needle valve is not letting any fuel into the float bowl.

 

I ahve to agree with dfisher1. I think control module (spark box). When they decide to die, that's it. I had a guy drive his truck over so I could do some work on it. He drove it over and parked it in the street, when I went to move it to the driveway it was dead, no spark.

 

Yep, thats what I'm saying. It will get NO gas at all...unless, of course, it is directly put into the carb....

 

76, I think you must have something wrong inside the carb. Clogged inlet, low float levels. Try looking down inside the carb and pumping the gas (engine off) to see if the acc. pump is squirting gas.

 

Same exact problem solved, had a new distributor, never used, new engine put back together all wiring double checked, couldn't get a spark to save my life. Tried everything then so back to square one. Checked ot the original shop manual, ignition section, followed the routine, checked the values at all the contacts with the good old VOM, found I had infinite resistance between the two pins of the electronic distributor coil (The purple and orange wires) brand new part= piece 'o junk. Got the distributor replaced --VROOM! Hot ziggety--generally speaking, the oil filled coils are pretty tuff, rarely go bad and the ignition module's the same way as long as you only make your connects and discons with the battery cable off--But I guess those little coils inside the distributor can be boogers, awfully skinny wires in there, don't bonk 'em around a lot or expect a problem...nooo not carbureator, c'mon! If that little coil is bad, incomplete circuit! You'll get no spark off the main coil and of course, no spark off the distrib...