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In my down time, while replacing the w/pump and radiator core, I rearranged the wires to the carburetor switch, to clean it up and make it look neat. (Not crossed in any way)
Subsequently, it will not start when the accelerator pedal is depressed.
I can jump the switch terminals by the carburetor switch and it will start, however dies out right away.
Is there an adjustment that I am missing?
Frustrated!
Thankfully,
Al

One side of the switch on the carburetor goes to the ignition switch, the other to the starter solenoid. Check the voltage at the carburetor switch with the ignition switch on, to make sure you are getting voltage. If you are, then put the meter on the starter solenoid terminal and put the pedal to the floor and see if you are getting voltage there. If you are getting voltage to the starter solenoid and it doesn't engage, check the starter solenoid ground.

Electrically, the coil and starter are both fed from the ignition switch directly but are independent. If stock wiring, nothing in the starter switch circuit would cause the instant quitting. Starter gets power off the GA terminal as do all the accessories and instruments. Coil gets power from the separate COIL terminal on switch and is only powered when key is to the right on later switches having the additional left or accessory position.

If you rerouted something that is now blocking full travel of accelerator, that might cause the start issue. The switch engages at a certain point near the max limit of travel. Here is some information on the carb switch operation and adjustment.

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Getting 6 v. at the carburetor switch.
At the starter solenoid I am getting 6 volts.

I didn't reroute anything. It is original stock wiring.
I can hear the click at the carburetor when depressing the gas pedal. The linkage to the switch below the pedal is engaging...
Still puzzled... It starts when jumping the carburetor switch, however when started it runs for a short time and then quits. As if it is not getting enough gas.
Thanks for the help guys!
Al

If it starts by jumping the two terminals on the carburetor starter but does not start when the throttle linkage is advanced then I'd take a look at the following possibilities:

1. The steel ball is not moving freely, or is stuck in its cylinder. This could explain why the switch isn't making contact. It could also cause a vacuum leak.
2. The sliding contacts aren't making contact due to a problem with the shims (unlikely).
3. The contacts are dirty.


You can undo the screw that holds the bakelite piece in place and extract the switch mechanism (careful... there's a spring). Take note of the orientation of the metal piece that engages the steel ball... it's possible to install it upside down. You can then blast the cylinder with carburetor cleaner to ensure the ball moves freely. There is also a fine screen that should be cleaned (see diagram provided by Howard). Carefully clean the brass contacts on the sliding switch (I use Brasso and a piece of cotton rag). Re-assemble.

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A bit confused. You say you are getting 6v at switch and 6v at solenoid yet no action at solenoid unless you jump the switch???

The switch could be at fault so one way to check is to remove wires again and place an ohmmeter across the terminals while you try the pedal. Should be a 0 or very low ohm reading happening about the time the pedal is maybe a 1/2 to 3/4 inch from floor. Any resistance at all is suspect.

The switch can be taken apart and inspected. Just follow the instructions and do pay particular attention to the orientation of the contact and number of shims as they mention. Here is an enlarged photo of switch from Service Counselor Vol 17 #1 showing the "W" shaped contact referred to very clearly.

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Thanks so much fellas.
I had some one depress the gas pedal, while watching the linkage at the carburator. If I press the linkage more toward the firewall by hand, a little further than it goes with the gas pedal, the starter is engaged.
However, adjusting the threaded linkage at the carb to try and engage the starter, has not lead to success. I suspect it may be a linkage adjustment, rather than the carb switch?? I don't want to take the switch apart if I can avoid it.
Any thoughts?
Thankfully,
Al

There are two adjustments on most. One on the passenger side from cross shaft to carb and the other on drivers side from accelerator pedal bellcrank to cross shaft.

When you change any of the adjustments it also affects other things connected to the cross shaft depending on what you have. Ultramatic is most important as changing things can affect the throttle pressure adjustment. If you have Ultra, I would suggest keeping the carb side the same length (assuming it was properly adjusted to begin with) to keep the same min and max range on the cross shaft. See if you can lengthen the drivers side to move accelerator pedal away from floor a bit more. If the accelerator bellcrank lever is already all the way back almost touching firewall, then no more can be gained so leave it alone. In that situation, will have to figure out what moved to change the linkage from when it was working.

If no Ultra or Electromatic then not a big deal moving either as far as cross shaft is concerned. Moving pedal back may affect kickdown switch if you have OD.

Thanks for the information once again. I have the 3 spd with the OD.
Sure is appreciated. Adjusted the linkage on the drivers side successfully.
Not sure what threw it off. However, I lubricated the linkage when I worked on the radiator and water pump.. Probably wasn't lubed in years and reacted too comfortably.
Now to give her a good tune up.
Al