Help identify these electrical components

[ChevyCruizer]

Sort story, I need help identifying the two electrical components in the picture below. They are located on the drivers side firewall just above and outboard of the main harness near the hood hindge. It is a 71 GMC 1500 non AC longbed.



Long story below:

OK, I just picked up a 71 GMC 1/2 ton that has sat for the last 8 years. It had no spark and the PO could not fix it. After draining the gas and cleaning the carb I got it started by running my own circuit to the coil and a short piece of fuel hose to a 5 gallon can. I started to troubleshoot the wiring (no spark) problem and let me tell you this guy must have used several spools of wire and tried to redo everything. I found full color diagrams here on the forum and was able to get it running "on its own power" from the key. I have now started to re-hook up all of the stock circuits but can not find these components or circuits on any schematic.

Any suggestions or help is greatly aporeciated.

Thanks, John

[JORGIE95961]

Originally Posted by chevycruizer

sort story, i need help identifying the two electrical components in the picture below. They are located on the drivers side firewall just above and outboard of the main harness near the hood hindge. It is a 71 gmc 1500 non ac longbed.



Long story below:

Ok, i just picked up a 71 gmc 1/2 ton that has sat for the last 8 years. It had no spark and the po could not fix it. After draining the gas and cleaning the carb i got it started by running my own circuit to the coil and a short piece of fuel hose to a 5 gallon can. I started to troubleshoot the wiring (no spark) problem and let me tell you this guy must have used several spools of wire and tried to redo everything. I found full color diagrams here on the forum and was able to get it running "on its own power" from the key. I have now started to re-hook up all of the stock circuits but can not find these components or circuits on any schematic.

Any suggestions or help is greatly aporeciated.

Thanks, john

smog and anti deisel stuff

[ChevyCruizer]

I have been reading and I think they are a time delay relay and transmission controlled spark (TCS) solenoid. So yes smog stuff

[SS Tim]

Here is something a little more exact. They are some of the Transmission Controlled Spark system components. Those color wiring diagrams are really generic and you would do far beter downloading a 71 chevy service manual and having much more specific diagrams and data. It is suprising how often these two relays generate questions here.

[ChevyCruizer]

I actually did download the service and overhaul manual. That is where I found the information above. Thanks for the help, hopefully someone else can use this in the future.

Have you found a factory assembly manual for download?