How many volts should I see at the choke

[axisg]

how many volts should I see at the choke ? I see 0.86 volts at the oil pressure switch then 0.75 volts at the choke with the car running. It took the car about 15 mins of running before the choke opened fully and it never got hot enought to pull it off high idle.

 

[t01blaze]

12 volts at the plug to the choke coil.

 

[axisg]

I did a little more digging. The clip onto the carb choke housing was all green with oxidation inside. Quick dip in muriatic acid cleaned that up now I see 10-10.7 volts at the clip.

I hook the lead back on to the carb and start the car. My voltmeter reading the choke coil the voltage counts downwards and levels off at appx 4 volts.

But now my choke light is on steady !?!

 

[pontiacgp]

what about the volts at the in and out side of the oil pressure switch?

 

[axisg]

what about the volts at the in and out side of the oil pressure switch?

Running 13.4 in & 13.4 out at the switch
10+ volts at the choke ( not plugged in )

Key-on but not running 12.5 in & zero Out
9.5 volts at the choke ( not plugged in )

I pulled down a schematic from mracing

On the Choke / Heater circuit there is a single 20amp fused line wired to the switch ( brn/wht )
then to the Oil Light Indicator (also brn/wht)
^^ both of these are on the same "hot" pole of the switch when plugged in.

Then from the switched side there are 2 wires
lt blue to the choke
dk grn/wht to the Choke Light indicator

Now I am curious as to why the choke light is on, and if it's on why the oil light is not on or vice versa.

My car was orignally CCC equipped but when I removed it originally and swapped over to the non-ccc dist and carb all the idiot lights and guages were unaffected.

It must be a simple fix, just need to wrap my head around how the wiring works and why the choke light would come on in the first place

 

[pontiacgp]

the choke lite goes on when starting the car as a test to the system. If it stays on it indicates an open circuit. With your key on and not running you should have 0 volts at the choke. That switch is to only permit power the choke when it has oil pressure to close the switch

 

[axisg]

correct, I am just trying to figure out what else is in-line with that circuit that would cut my voltage back from 12v + to the 10v or less I am seeing at the choke

 

[pontiacgp]

did you check the volts at the fuse?

 

[pontiacgp]

any updates?

 

[axisg]

no update at all, super busy with both work and projects that need to be finished before winter at home so the Monte has been parked.
However I am am still confused about the drop in voltage over such a small length of wire and why the choke light is on but not the oil light as the diagram I have here shows them on the the same circuit.

The next plan of attack is to cut and splice in a new wire from the oil pressure switch to the choke. If that doesnt fix it then the dash cover will come off to check the wiring to the choke and oil light. If that doesnt do it then the choke light will be pulled and I will just splice into the wiper motor circuit to give it the 12v it needs 🙂

BTW I have 13.5 in and out of the fuse with the car running
13.5 in and out of the switch with the car running ( I pull the plug off off the switch and install a jumper wire from the hot side of the plug to the switch then measure the voltage coming out of the switch )
When I place the plug back on the switch I only get 10 ( ish ) or so volts out of the switch. This means to me there is something drawing current which I can only assume is the choke light or some break in the wire because the readings keep fluctuating on my Voltmeter from 6-10v.