74 620 Electric Choke

[Kirden]

Hey guys, I have found a lot of different opinions on this so I wanted to get a clear answer. I bought and installed a 32/36 weber with electric choke. I was wondering did my truck come with a stock electric choke wire? It is a 74 620 with the stock L18 but the PO replace the hitachi carb with a manual choke rochester from and old GM.

 

The wiring diagrams sticky did not help because the diagram does not work for me. It says the server is not available. I have seen people suggest wiring the choke to anything with 12v with the ignition on, but as the PO also decided to use an aftermarket hot rod ignition (it is mounted on the kick panel...) I am not sure if ecverything is wired correctly. Another thread said to wire it to the hot side of the ballast, but if my truck has a stock electric choke I want to use the stock wiring. Here is a pic I snapped showing some of the wires that go to now where:

 

 

This set of wires is between the brake booster and throttle cable hole from the firewall. It comes from the following connector that runs along the firewall from the main harness:

 

 

Coul one of these wires be the stock wire or am I looking in the wrong place?

[banzai510(hainz)]

how about put  then the key to ON and ck with a volt meter and see if you get 12volts. If yes then use that for your choke.  If you got a idle Selinoid cutoff also you could daisy chain the wire from choke to the seliniod  to get that running also.

SIMPLE.

[Kirden]

Sadly I can't find my multimeter. That was why I was asking if anyone knew the exact stock wire. I prefer not to rig wiring, esp when it is 40 years old. If I can find the original wire I will use that, if not it looks like I will be running new wire from the ignition switch with a relay and fuse between, or running that same setup but going to the hot side of the ballast instead of the ignition.

[banzai510(hainz)]

I cant seeing see doing all that fuse crap when its one of those wires right there and its for the choke.

 

Home Depot/Walmart has Chinese made meters for about 10$ get one than rigging up a wire with a fuse to a realy to this and that and to the rear left turn signal.

 

doesnt oldddatsuns.com have the wire diagrams for the 620 in the tech section?

 

you have a test light? those are even cheaper at about 3 to 5 dollars. Turn key ON test light lights up you know you got 12volts

[Kirden]

Haha, I'm sorry man, I completely read what you said wrong. I thought you meant check for any 12v source, not check those wires. I am kind sleepy stupid at the moment. I will see if I can find my multimeter and check those three wires, hopefully one of them is in fact the 12v source.

 

The relay/fuse thing was only if I couldn't find the original wire. I will check out olddatsuns but I know the links in the sticky do not work, or at least they don't work for me.

[Kirden]

Thank you for the info on olddatsuns.com That diagram is awesome. One less thing to figure out so I can take the weber on its maiden voyage :)

[datzenmike]

Of course the idiot PO painted all the wires. Pick the paint off. The auto choke heater wire is the Blue/White stripe wire and will/should have 12 v only if motor is running. If not available then use the idle cut solenoid wire White/Blue stripe, as Hainz suggested it will only have power with the key ON.

[Kirden]

Thanks guys, picked the paint and tied into the blue/white wire. Let it get to temp and ran like a top. Tried to rig the throttle cable and went to back out, throttle cable came loose :P For the 5 feet I got out of it it sounds great and pedal response was better than the old GM unit.

 

I might have to get more creative with the throttle rig. The old choke cable was caught between two nuts on a bolt, held for the entire time I have had the truck so I guess thats what I will do for the throttle till I find something better.

 

I'm happy that I finished this and didn't screw it up. It is much easier than figuring out EFI setups, but it is also scary cause it is all new to me. This truck will be a really fun process :)