1974 seatbelt interlock switch

[zies8]

ELectrical issues usually are difficult for me. My question is about the seatbelt interlock switch that if I am not mistaken is exclusive of the 1974 model year.
After 4 years of working on my frame off of my 74 convertible I have the body on and am very close to being ready to start the Engine. I am trying to get to the point where I know that I have ignition. I have tried to turn the engine over but have not had any luck getting the starter to turn. Here is what I have done so far.
1. Hooked up harness that goes to the Starter. My manual Haynes says that the wiring connections are determined by the size of the connector matched to the size of the lug.
2. Battery Ground is connected w/ good ground to frame.
3. All of the enbgine compartment wiring is connected with the exception of a couple of plugs under the brake booster that I cannot Identify. And the yellow wire that I assume to be the positive to fusebox from starter? Does the positive juice for the car originate at the starter through this wire? I have tried connecting it to the lug at the starter + side and still do not get ignition.
4. I have connected the coil to the wires that are associated with it. The question that I have concerning the coil wiring is about the +/- terminals. My service manual does not differentiate between the pos / neg. Does it matter how the wires are connected? I have the black wire from the bottom of the distributor connected to the pos side and the wire from the resister or whatever that thing is that is connected to the side of the coil mount attached to the neg side.

This has been long winded and I hope that I have described my situation properly.
The question I have finally concerning the seatbelt interlock switch under the seats. Do I need to have that entire system connected before I will get ignition?

Appreciate your responses.........................Mike..........Utah

 

[aapple]

The yellow wire should go to the "R"(the one towards the outside of the car) terminal on the starter solenoid. This is the 12v feed for the coil(only "hot" when in "start" or "run"), and should be attached to the "+" terminal on the coil, as well as the resistor wire from the ign. switch. The black wire from the dist. should be on the "-" terminal of the coil.
You can simply unplug the switches under the seats to dis-able the starter interlock. In order for the interlock to work, you have to be seated in the car first, and then fasten the seatbelts before attempting to start. (This is assuming everything is working as it should to begin with!) Just unplug the seat switches, and then get it running. Then you can go back to seeing if the interlock system functions.
ALL '74 GM cars had this system, and some very early '75s.

The "resistor" thing on the side of the coil is a capacitor, for RFI suppression, and should be connected to the "-" side of the coil.

 

[zies8]

Thank you aapple; I just recieved the assembly manual for my car. This manual is worth 10 times what I paid for it on e-bay.
It was a major mistake not having the assembly manual from the start of my project.

You answered my main question. I really needed to know if the interlock switching was my problem with ignition. I do not have any of my seats or setbelts installed and therefore according to your reply I should be able to cross that off of my list of squawks hindering ignition.

Thank you again my friend..........Mike

 

[chevy6673]

The yellow wire should go to the "R"(the one towards the outside of the car) terminal on the starter solenoid. This is the 12v feed for the coil(only "hot" when in "start" or "run"), and should be attached to the "+" terminal on the coil, as well as the resistor wire from the ign. switch. The black wire from the dist. should be on the "-" terminal of the coil.
You can simply unplug the switches under the seats to dis-able the starter interlock. In order for the interlock to work, you have to be seated in the car first, and then fasten the seatbelts before attempting to start. (This is assuming everything is working as it should to begin with!) Just unplug the seat switches, and then get it running. Then you can go back to seeing if the interlock system functions.
ALL '74 GM cars had this system, and some very early '75s.

The "resistor" thing on the side of the coil is a capacitor, for RFI suppression, and should be connected to the "-" side of the coil.

yes i also had some problem with the seat belt system on my early 75 i bypassed it at the reset box good luck

 

[JohnZ]

The "resistor" thing on the side of the coil is a capacitor, for RFI suppression, and should be connected to the "-" side of the coil.

The radio capacitor wire gets connected to the (+) terminal, not the (-) terminal.

 

[aapple]

:duh :duh :z :BOW
Thanx for the catch, there...John!!!!

 

[zies8]

The radio capacitor wire gets connected to the (+) terminal, not the (-) terminal.

Thanks for the response you guys. I just recieved my assembly manual after working on my frame off for 5 years. Talk about a big mistake. I should have never been without it!!!!! Some lessons are learned the hard way...

 

[JohnZ]

There's a good article on the '74 Corvette seat belt interlock system (and how to defeat it) at www.corvettefaq.com .