Cut-out to Terminal Wire & Amp Mtr Issue

B

Bill O'Brien

Senior Member
Cut-out to Terminal Wire & Amp Mtr Issue / Voltage Regulator

Well, after a long and challenging road after installing my new Snyders 5.5 head it was time to set the timing. That went well and I wanted to check to see if there was any spark. So I connected plug #1 and turned on the ignition.

Smoke! Almost made a dive for the fire extinguiser!!! My amp meter was basically burning up and my cut out to terminal wire started to fry. It was smoldering and the rubber on the wire was melting. I flicked my batter cut out and turned off the ignition.

Luckily the car had no gas in it (ironically one of the isses I just fixed was a leaky gas gague!!!).

The cut out to terminal wires are obviously shot. Also, the rubber on my cut out melted. The wiring from the terminal including the wires to the amp meter are fine. I opened up the cut-out and it looks fine too... other than the melting on the outside.

I re-checked my wiring diagram... coil hooked up correctly, wires into and from the terminal hooked up correctly. I removed the cut out to terminal wires from the metal 'tube' they are housed in. They did not show any issues other than the melting..... obviously I have something either faulty or installed incorrectly... ????

What could have caused this? I am ready to order new parts but I do not want to just fry them again!!!!

Thanks gents!!!
 
Last edited:
Do you have a repro cutout? I've seen the covers touch the output terminal and short to ground. This usually happens when the insulator around the output terminal is broken. Even a small chip in it can allow the cover to touch and short the terminal to ground.

If you have an original cutout, maybe the output terminal screw is too long, or the insulator is missing.
 
"car was running before I started my restoration of the engine compartment"

I would back track and re-check everything I "touched", possible pinched wire? Sounds like you will be re-wireing. Do one 'circuit" at a time, isolate the others and run continuity checks before applying power. Please keep us up-dated. And, good luck.
Paul in CT
 
If I recall correctly the only thing the key does is connect the coil to the points. If everything is wired correctly this suggests the coil is shorted and when you turned the key on it caused a dead short from - to + through the points assuming they were closed.

I would check your wiring and if everything is correct ohm out the coil carefully. From what I see you should have a red wire going from the key to the coil. From the other side of the key you should have an armored wire going to the distributor. These wires should not be connected to the terminal block in any way other then simply passing through.
 
Did the smoke start after the ignition was turned on, or did the smoke start after the battery was connected?

If it started after the key was turned on, then you have at least two problems.
 
Luckily the car had no gas in it (ironically one of the isses I just fixed was a leaky gas gague!!!).

So the dash was taken of to do the repair and after replacing it you may have had a loose wire touch the tank??
 
Bill O'Brien said:
The car was running before I started my restoration of the engine compartment.
Click to expand...

Had the same trouble with mine when I got it and it was wired wrong, I would check the wiring diagram again and add a fuse to the feed wire coming off the starter if you don't have one already.

A11450SF-7248.jpg
 
Last edited:
Tom Wesenberg said:
Did the smoke start after the ignition was turned on, or did the smoke start after the battery was connected?

If it started after the key was turned on, then you have at least two problems.
Click to expand...

Good point Tom,

"So I connected plug #1 and turned on the ignition. "

"My amp meter was basically burning up and my cut out to terminal wire started to fry"

The key should have absolutely no effect on the cutout wire if the generator isn't spinning.
 
If you have the metal conduit for the wires from the generator to the junction box, there is the possibility that it shorted against the left hand side of the terminals in the junction box. When that happens, the ammeter becomes a fusible link and will make a lot of smoke until one of the hot wires or the ammeter finally burns through (without a fuse in the system). Gar Williams
 
It may be a wire touiching the gas tank on the back of the dash... but why would only the wire from the terminal to the cutout and the amp meter fry??? All new wiring....

thnx!
 
Aerocraft said:
If you have the metal conduit for the wires from the generator to the junction box, there is the possibility that it shorted against the left hand side of the terminals in the junction box. When that happens, the ammeter becomes a fusible link and will make a lot of smoke until one of the hot wires or the ammeter finally burns through (without a fuse in the system). Gar Williams
Click to expand...

This may be the issue... not sure if it was / wasn't touching when I took the terminal apart... great idea of what to look for!!
 
Additional info to consider:

If work was done on the cutout ( you said you removed the cover and looked inside after the short happened so the cover was not welded or soldered to begin with) I have seen this happen when someone cuts the welds on a cutout to work on the insides ... when they replace the cover they rotate the cover just enough so that it shorts out the SCREW that holds the wire going to the terminal block which takes the ampmeter to ground.

Also screws too long short some cutouts inside as mentioned
 
Last edited:
If it was shorted, there will be the witness mark of a short at the flared end of the conduit and on the terminal post. As a suggestion, since having done that myself, I add a thin nylon washer at the flared end of the conduit to act as an insulator. The washer will have to be split to get it over the two wires. Gar Williams
 
Ok, new parts ordered..

Terminal to cutout wire in metal tube
Amp meter
Cutout bolts and rubber washers
And a few extra tid bits!!!
 
The repro steel tubes I've seen didn't have the cutout end flared as the original is. I heated the end red hot with a propane torch and used a punch to roll around and flare the end.
 
Ok... I am 90% sure it was the cut-out that shorted out the system. There are black burn marks on the hole near where the screw holding the wire to the terminal goes. This is also where the rubber melted.

Now, my cut-out does not have a top that is welded. This is how the 'top' came down and into contact with the screw. Thinking of buying a new one fron Snyders.... are they welded??

I have my new terminal to cut-out wire metal cover almost ready to install after a bit of paint work!
 
You must log in or register to reply here.
Back
Top