New guy with electrical question 74 powerwagon

[74PW]

Hi I'm new to this site and have little knowledge of wiring system, I picked up a running 74 powerwagon with running 360 for 300, the guy was going to take to the junk yard. So I've been going through it. Whoever had a wiring nightmare I started with taking all the bs wiring out. Thats when I discovered the main power supply to the firewall plug had shorted at one time and destroyed the socket, I hardwired it through the firewall and had good power back. Then the truck would not stay started unless I held the key in the start position...so I started scratching??/ Thats when I found out it looks like the ecm on the fender had been removed and some wires from the 5 pin plug were jumped together. well I found that one of the jumped wires came loose so I put it back together and the engine runs fine. I checked the distributor and it does not have points. I just do not know what I have here?? The 360 has an accel coil edelbrock intake and carb, headers, and I havn't taken the v covers off to see what heads are on it. Question is , Has anyone seen this done or any clues on the wiring? Thanks

[W_A_Watson_II]

Welcome to the site. So there isn't a Chrysler ECU and the wires are jumper-ed between some of the connector?

I'd start chasing the wires and looking for where a control unit might be and what it might be.

[74PW]

I looked there is none in sight.. All it has is a voltage reg and two pole resister on the firewall.. The wire harness is there on the fenderwell and an outline of where the ecm and resister were but the wires are just jumped together??? but those parts are gone.. The motor runs fine. I think probably tired but fine

[W_A_Watson_II]

I wonder if it has a HEI Distributor or pertronix ignition module installed? A picture would help, also where are you located?

[74PW]

I'm In Reno Nevada, I can get some pictures tomorrow. This guy had wires everywhere, to 7 different rocker switches that went nowhere ... I removed all that bs. The wires at the five plug were jumped with two female connectors that came loose. I hard wired them back but I just want to be sure whats going on. ...Just another learning thing I guess

[74PW]

http://imageshack.com/a/img540/2863/E8zr35.jpg
http://imageshack.com/a/img540/2792/gwa4YC.jpg
http://imageshack.com/a/img633/7859/Ru15ro.jpg
http://imageshack.com/a/img673/6763/6mFFsy.jpg
http://imageshack.com/a/img661/8048/stEbsy.jpg

here are some pictures you can see where the wires are jumped I assume but not sure they were connected to a 4 post resistor.

[W_A_Watson_II]

The Pick-up coil in the last photo doesn't look like a stock MoPar, trace the wires coming out of the distributor back and see where they go. Also see what it says on top of the pick-up coil.

Pertronix Ignition module - Ignitor II

[74PW]

Ok I want to thank you first for your time, The pick up is a Pertronix Ignitor
Lot # 03AII ,
NV5
The distributor has only two wires; one to the resistor and other to the coil, only thing I can figure is whoever jumped the wires from the loom going to the old electronic and resister, ],.Some work has been done to the motor I think, headers edelbrock intake and carb, I just opened up the valve cover and the casting on the head is 3418915-6 and the have an upside down J between the plugs but the block is date stamped 74. The motor runs fine while parked,sounds strong and really revs, but as soon as I put it under load it"s really doggy, like has the Hp but no torque. It has the big#9 8 /3/4 rear but when I was doing the brakes it feels like a lot of resistance and no end play.. possibly the adjusting nut needs to be backed off??

[74PW]

The compression is a consistent 115 all the way through.

[W_A_Watson_II]

No problem, there are always PW lovers here willing to help.

Sounds like you have a Pertronix Ignitor II, thus there isn't an external ecu. And you now have the opportunity to clean up more wiring.



Timing sounds to be the issue, you might need to check and adjust it. Not sure what modifications were done or needed in the distributor for the Pertronix, but you might need to read up on it.

Sorry, can't help you on the 8-3/4, but I'm sure someone here will chime in.

[74PW]

what about the compression? is it in range? The chilton book I have just says as long as it is no greater than 80% diff between cylinders. but I'm not sure whats the norm.. and I have't found it doing a search.

[74PW]

I'll take the harness apart and get rid of everything not needed

[W_A_Watson_II]

depending how you did the compression test, 115's not bad, I think the older MoPar small block 318 minimum is 100. Older stock is I believe 130-135.

[74PW]

just a cold test, throttle closed

[74PW]

I'm having a **** of a time finding a wiring diagram specific to the 1974 W100, The wire colors were changed somewhere in between years and the diagrams I have are not the same. Anybody have one? For example the colors to the horn on my truck are light green w/white stripe, the other; white powers when in run position.