Hello, I have a 74 FJ40 with an F155, desmogged, that I installed a MAF "lightning strike" HEI (mechanical advance) in place of the OEM vacuum retard dizzy.
This is what I've done, I have no doubt you will find I've not done it correctly, if I had I wouldn't be asking for help getting it right.
I've left the OEM coil/ballast resistor/igniter installed so far in case I have to go back to the old Dizzy. When I first installed it, I learned the "one wire hook up" was not correct, because I needed switched 12v power, and 12v starter power because the switched power cuts out while the starter is cranking, meaning no spark. So I took power from the +12v post on the coil where I found cranking volts, and power from the black/yellow wire near my starter.
FYI, I have a gear reduction starter that only has a black/white wire to it (plus battery lead and ground).
My 40 ran well and started easier than it had; until recently that is. Ive been having trouble starting it where its cranked and cranked before firing, and yesterday it wouldn't start at all. I knew I had fuel and air, so I tested spark and got none. I then tested for switched power, which I still have, but my cranking power is gone. I no longer have cranking volts available from the + post on the coil.
When I wire the HEI direct to the battery and crank it over it starts instantly, so I'm confident this is the problem.
The MAF directions said to use the original Dizzy wire, the DUI directions say I need alternator voltage (not sure how to get that).
Can someone help me get my wiring straight? Where is the appropriate place to pull power from for a one wire HEI that gives me cranking and running volts?
Once I get that figured out, can I just disconnect the old coil/ballast resistor/igniter and take all that out?
Thank you!
This is what I've done, I have no doubt you will find I've not done it correctly, if I had I wouldn't be asking for help getting it right.
I've left the OEM coil/ballast resistor/igniter installed so far in case I have to go back to the old Dizzy. When I first installed it, I learned the "one wire hook up" was not correct, because I needed switched 12v power, and 12v starter power because the switched power cuts out while the starter is cranking, meaning no spark. So I took power from the +12v post on the coil where I found cranking volts, and power from the black/yellow wire near my starter.
FYI, I have a gear reduction starter that only has a black/white wire to it (plus battery lead and ground).
My 40 ran well and started easier than it had; until recently that is. Ive been having trouble starting it where its cranked and cranked before firing, and yesterday it wouldn't start at all. I knew I had fuel and air, so I tested spark and got none. I then tested for switched power, which I still have, but my cranking power is gone. I no longer have cranking volts available from the + post on the coil.
When I wire the HEI direct to the battery and crank it over it starts instantly, so I'm confident this is the problem.
The MAF directions said to use the original Dizzy wire, the DUI directions say I need alternator voltage (not sure how to get that).
Can someone help me get my wiring straight? Where is the appropriate place to pull power from for a one wire HEI that gives me cranking and running volts?
Once I get that figured out, can I just disconnect the old coil/ballast resistor/igniter and take all that out?
Thank you!