I'm just gonna be honest I searched and I'm not sure if I'm just lazy or dumb. But sometimes it's just easier to have other people give advice and step by step diagnostics then piecing together others previous problems. So if yah feel like helping feel free or just bust my ***** lol

So here's the story:
Picked up a 78 f250 351m tow truck at a estate auction. The truck has been sitting a few years. I popped the hood and notice the dizzy cap was off and rotor missing as well as a newer looking aftermarket duraspark box that looks to have been installed. Also find a new magnetic pickup sitting on the fender which looks to have collected a decent amount of rust particles. After my purchase a gentleman walks up tells me that the previous owner had a problem getting the dizzy out. Gave up got sick and passed on.

Fast forward to now. I get the truck home decided to just replace the rotor put it back together got it to crank no start no spark at plugs

Step 2 get dizzy out which was stuck as all hell. Finally got it out. Cleaned up new pickup that was on fender. Installed and still no spark at plugs.

So what I'm gathering previous owner may have had the same problems with no spark I think he replaced the duraspark first then possibly started on the pickup but failed there.

My questions now
What should I do where should I start. What's square one? I feel like gotta go back and retest everything. And narrow it down!

So who's got a good plan for me lol

 

Scoop, work backwards from the distributor.
Is there spark from the coil to the cap?
If so could be a cracked cap, faulty rotor.
If not,
Is there 12 volt to the coil?
If there is nothing at the coil next step would be to test the ignition module. You mentioned it's an aftermarket module....for the price of a new one you may consider replacing it. Then you'll know we're you're at.

Keep us posted.

 

So I havent touched this truck in months well almost a year i had a day off and decided it was time to try and get it to atleast fire up. ( I have it stored 20 mins from my house so I never seem to have all my tools or the right tool with me whenever im there and since it wont fit on my trailer I cant bring it home) Since my last post I got a box of new parts for $20.00 dizzy cap rotor plugs and wires figured id give it a try. Replaced Reinstalled and well first time I got some popping sounded like a slight back fire out of carb nothing really but i decided the dizzy was out 180. checked it and believe I have it in correct now. (balancer marks are very very unclear tried sanding but cant hardley make anything out bump started it till thumb blew off #1 hole the rotor was then lined up with #1 wire at cap figured im in the ballpark) anyway now it will spark when turning over (pulled wire did the old screw driver test) but i cant get it to fire or jump or gurgle or anything. I plan on grabbing a 15/16 deep socket and double checking the timing. I can barley make out atc some degree marks on the balancer and btc where exactly should it be lined up with the marker at?

also if it is set right what else could it be. (been using starting fluid in carb since i know it has a bad fuel line but it still should fire or jump)

could the module be bad even though im getting some spark? Not enough spark maybe?

 

Anyone lol

 

Go back to basics... is the dizzy 180° out?

What color is the spark? A weak yellow one or strong blue/white?

Voltage checks! Connector checks

How much slack is there on the timing chain? Remove the cap and put a socket on the crank and rock it back and forth. Some is Ok. Alot is not... you may have to cheat the timing to get it to light off.

 

Spark seemed yellow but was wearing battery down after 3 hours of tinkering

 

Make sure firing order is correct and in the right direction on the dizzy.