early GM HEI ...with vacuum advance and 4 prong module.....NO SPARK !! Have replaced (with new NAPA stuff)---coil,module,rotor,pickup,cap and harness between dist. and cap (the part with the capacitor on it) .... nothin's left !! Why no spark ?? I DO have voltage at the B+ terminal...12.6 then drops to about 9-10V when cranking..ALL components test out/ohm out good !! What the hell am I missin' ??? suggestions ??? Jersey Skip
Bad ground to the distributor (engine)??? "Jumper clip" thingy not installed in the cap right??? Hot lead/Tach lead reversed??? Coil contact button not installed???
hack... have continuity (ground) between coil-,dist housing and engine ....Jumper clip ???? Hot lead is correct...coil button is in cap and "spring thing" is between cap and coil........... ?????????? Jersey Skip
The "jumper clip" is that metal insert in the cap...the leads plug into it and it carries electricity to where it's going...I seen people leave 'em out or install them wrong...no spark!
Hack... yea, they're in right ....and all connections are good ---- 12V in and 3 leads to dist. Jersey Skip
Well, SHIT!!! Toss that paperweight and run POINTS!!! Didja test the coil...the OLD way? (Take it out...have a buddy, neighbor, innocent child, etc put their finger on the Yikes Pad(tm), then, with one lead grounded, flip the positive lead across a 12v supply a couple of times. If they look at you blankly wondering what you're doing, the coil is bad. If they pick themselves up off the floor and kick you in the shin, cuss you like a sailor or say "Whoa, Dude...do it AGAIN!", your coil be GOOD!)
hack..if I had a points dist. it woulda' been IN THERE ! The coil reads 2.5 ohms across the terminals(which is perfect for an HEI) and it's new ....kinda' hard to do the 'old way" but I'll rig up a setup tomorrow (think I'll use a coil wire instead of zappin a buddy---he he he ...). Everything is NEW !! I even ran a 12 ga. ground wire from the coil to the engine/frame ground and am using a piece of 14 ga. wire for a plug wire so I know it CAN'T be the wire ..... jersey Skip
You say you have no fire. Where? At the spark plug? Take the cap off, disconnect the hot lead to the cap. Have someone crank the engine while you watch the rotor. Hope its turning! If it doesn't you most likely broke the distributor shaft or sheared the roll pin in the gear.
what is this being installed on- has it run before? is it hooke to a "resistor wire" lead/or an inline resistor? or worse is it hooked up to a wire smaller than 10 Ga? last but not least where is the source of your Hei lead?is it from the relay term on solenoid/-If so thats it.JUST SOME THINGS TO LOOK AT- I'm NOT BEIN SMART.
Choprods...350 chev roller motor...yes, has run ...car is wired to start/run/charge only(on-off sw. for ign. and momentary make button for starter )...all 12 ga. wire....all power comes off MAIN POWER LUG on starter and are fused ... Jersey Skip
Check the starter windings. 9V isn't enough to fire the coil. Starter is drawing to much current when cranking. My 2c, Stevie G
Take an second dist that is working, replace one part at a time from your original dist until your second dist no longer works. last part installed is bad.
OK boys.... here was the problem .....module takes TWO screws to hold it down (It had ONE when I opened it up so I ASSUMED it was correct...)installed second screw ( which GROUNDS the module---DUH !!!) and ZAP !!!! LOTS of spark now ...thanks guys and file the missing screw scenario in your "what the hell" file ........ jersey Skip
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