Electrical 304 v8 HEI Crank No Start NO Spark issue,
20Fathoms
Jeeper
My thanks to all who share their knowledge on here, super site for good info. Recently picked up a '79 CJ7 project and I'm hoping for some opinions on a crank but no-start issue. Please excuse the lengthy background but I figured more is better...
For now we're just trying to get it moveable under its own power pending a comprehensive resto - '79 w/ AMC 304, T-150, Dana 20, Dana 30/Dana 20 axles, MC2150 2bbl carb on an Edelbrock intake; from the available head numbers/VIN/VC etc it appears the engine/drivetrain are original. The PO installed an aftermarket HEI dizzy and Packard 8mm plug wires, but could never get it to fire off... (PO did install the original jeep dizzy gear on the HEI).
Before any start attempt we:
1) Pulled the dizzy - verified a non-hardened gear was installed, bore scoped the WP cover and found what appeared to be a new timing chain (looked indexed properly at TDCC but the view angle was somewhat Limited). Reinstalled the dizzy on verified TDCC and with correct firing sequence on the wires. Installed new plugs/antiseize (Autolite copper 65s at gapped at 0.045).
2) Cleaned every connection on the battery cables, solenoid, grounds, starter, dizzy hold-down clamp etc.
3) Installed a rebuild kit on the MC 2150, and new fuel filters, gas, and verified good fuel flow at the venturis.
When we try to key start, the engine will crank strong but not fire at all...not even one solitary pop from the pipes. The battery was at 12.66v and drew down to 11.2 v on start (when measured at the battery terminals and HEI Batt wire). This battery started a 5.9L Cummins and SBC 327 with no problems after the CJ attempts, so I'm fairly sure the batt is not an issue.
The distributor looked new, the contacts on the cap/rotor didn't look like they had ever carried any current; there was no dust buildup around the rotor/cap, no burn marks, frayed or pinched wires etc., the only 'used' looking part was the gear. The coil showed .6 ohms on the primary circuit and 8k ohms on the secondary, the magnetic pickup was at 880 ohms between the green and white wires. We pulled and grounded the #1 plug while cranking and didn't see any spark. Thinking some weirdness was afoot, we swapped the coil and ignition module for new NAPA branded ones we keep as spares for our SBC 327 - no change.
The ignition wiring was pretty scary...looked like PO was trying to feed the HEI with a resistance wire off the main bulkhead connector. We rigged a remote 12v feed to the HEI from a completely separate battery, and rigged an external ground wire from the dizzy body to the block...again no spark energy.
We're pretty much out of trouble shooting ideas on this thing...short of scrapping this aftermarket unit for original ignition or an MSD Ready to Run dizzy/coil.
Thanks in advance for any ideas...
For now we're just trying to get it moveable under its own power pending a comprehensive resto - '79 w/ AMC 304, T-150, Dana 20, Dana 30/Dana 20 axles, MC2150 2bbl carb on an Edelbrock intake; from the available head numbers/VIN/VC etc it appears the engine/drivetrain are original. The PO installed an aftermarket HEI dizzy and Packard 8mm plug wires, but could never get it to fire off... (PO did install the original jeep dizzy gear on the HEI).
Before any start attempt we:
1) Pulled the dizzy - verified a non-hardened gear was installed, bore scoped the WP cover and found what appeared to be a new timing chain (looked indexed properly at TDCC but the view angle was somewhat Limited). Reinstalled the dizzy on verified TDCC and with correct firing sequence on the wires. Installed new plugs/antiseize (Autolite copper 65s at gapped at 0.045).
2) Cleaned every connection on the battery cables, solenoid, grounds, starter, dizzy hold-down clamp etc.
3) Installed a rebuild kit on the MC 2150, and new fuel filters, gas, and verified good fuel flow at the venturis.
When we try to key start, the engine will crank strong but not fire at all...not even one solitary pop from the pipes. The battery was at 12.66v and drew down to 11.2 v on start (when measured at the battery terminals and HEI Batt wire). This battery started a 5.9L Cummins and SBC 327 with no problems after the CJ attempts, so I'm fairly sure the batt is not an issue.
The distributor looked new, the contacts on the cap/rotor didn't look like they had ever carried any current; there was no dust buildup around the rotor/cap, no burn marks, frayed or pinched wires etc., the only 'used' looking part was the gear. The coil showed .6 ohms on the primary circuit and 8k ohms on the secondary, the magnetic pickup was at 880 ohms between the green and white wires. We pulled and grounded the #1 plug while cranking and didn't see any spark. Thinking some weirdness was afoot, we swapped the coil and ignition module for new NAPA branded ones we keep as spares for our SBC 327 - no change.
The ignition wiring was pretty scary...looked like PO was trying to feed the HEI with a resistance wire off the main bulkhead connector. We rigged a remote 12v feed to the HEI from a completely separate battery, and rigged an external ground wire from the dizzy body to the block...again no spark energy.
We're pretty much out of trouble shooting ideas on this thing...short of scrapping this aftermarket unit for original ignition or an MSD Ready to Run dizzy/coil.
Thanks in advance for any ideas...