TR2/3/3A Electrical Problem

I'm at a total loss on this one. This morning I started to remove the rear air cleaner and accidently grounded the cable from the battery, at the solenoid. I have negative ground. I know, I should have removed the ground before starting but I didn't. Anyway, I removed the ground and then the air cleaner. When I reconnected the ground I had nothing. No electrical power to the car at all. First thought I might have blown a fuse. No, all checked good and when I checked voltages with the negative probe at the battery terminal I had 12+ volts everywhere. With the negative probe at any other ground on the car I got nothing. I removed the ground strap from the battery and checked continuity from other places on the car and the grounding strap and all was good. But when I put the ground back on the battery there was no continuity between the grounding strap and any other place on the car. I checked voltage on both sides of the solenoid and found I had 12+ volts at both locations. Then removed the lead from the started and found I still had 12+ volts coming from the starter. I have a high torque starter from Classic Car Performance and I have called them to see if they have any suggestions. Haven't heard from them. In the meantime, does anyone have any suggestions?

A little more. The starter is bolted to the car with no wires attached. With the ground attached to the battery, put the negative of the multimeter to the negative of the battery and the positive of the multimeter to the input on the starter. Read 12+ volts on the multimeter. HOW????? Where's it coming from?????

Are you sure you're using the multimeter right? On a voltage range and not on a resistance range or something else? Leads plugged into the right jacks?

Having a voltage on the starter with the cable disconnected is just not possible.

I totally agree. It should not be possible but it is happening. That's why I'm totally confused. Yes, I'm using the multimeter correctly. As I said, when checking resistance there is none with the ground cable disconnected and checking to other parts of the car; however, once I connect the cable to the negative post on the battery it goes to infinite. I'll see if there's any way I can take a picture of this because I don't believe it and I'm seeing it. Twelve volts at the starter with no cables attached. How could it happen???????

Possible fault in solenoid? Possible discontinuity of the ground cable? (Terminal on cable electrically disconnected by the short or the manipulation of disconnecting it after?) Continuity engine to frame, frame to body, engine to body?
Bob

It sounds like the ground cable to the body had a weak ground to begin with, and the short fried it. I'd clean the connections on that ground, and then clean the left engine mount ground cable.

What kind of battery cable ends are you using? I am sure they are high quality, but I have to ask. Are they sealed into the insulation of the wire itself or are they added on to the end of the wirer and removable? Quality of connection is so important. You basically turned you battery into a welder for moment and something open up somewhere because that was easier for the system than welding your wrench to car tub. Electricity always takes the path of least resistance, even if that means blowing something open. As to why they is power at the starter, I would think the battery was still hooked up. After a belt has broken quickly, I have seen generators turn into fan motors and just spin and turn on their own ===without the engine running, kinda trippy. Unless there is a capacitor or something storing electricity I do not know you are getting voltage reading. Perhaps you are saying the solenoid toasted and is letting 12v go down to the starter?

Do have high quality cable ends. I also figured something opened but can't see what since the short occurred at the solenoid end of the battery cable. Seems current would have flown battery to ground and not through anything else but apparently it did. I checked to make sure I hadn't fried the solenoid by pushing the button on the end and checking continuity. It makes when the button is depressed. For those familiar with the TR3 wiring, if I remove the brown wire from the solenoid it obviously removes power from the fuse box and all things associated with that but it also removes power from the starter. And this is while there are no wires connected to the starter so it must be going through "ground". When I typed that a dim light went on so I went out to the car. With the battery hooked up and the brown wire connected I put the negative lead of the multimeter on the negative battery terminal, turned the ignition "on" and was able to read 12 volts at any ground point on the car (engine, carb, radiator support, etc.). I now have a better idea of what I have but have to figure out why and how to correct it. Any ideas will be appreciated.

When you shorted the wrench, current went battery to block, block to frame, frame to body, and body to battery. Those are the connections you need to concentrate on. Everything you are describing is to be expected from a bad ground at one of those locations. Check and clean them first...then we can get a better idea of what is going on, if that doesn't fix the problem altogether.

The solenoid did not see the short, as you shorted to the input, not the output of the solenoid. The starter also could not have seen the short, as it was not hot when you shorted. So those are 2 items you can ignore for now.

You can show voltage across a bad connection, since the voltage tester uses practically no current to check the voltage. But, when you attempt to run significant current through the same connection, it has so much resistance that the voltage then drops to zero. Check your ground cables at the left front engine mount and on the body above the battery. At least unbolt them and rebolt back to get fresh connections at these points.

By the way...this is Randall's kinda thing. Have ya'll noticed he has moved to the other forum? Did we upset him or something?

Been wondering where Randall disappeared to. Was looking forward to his weighing in. Anyway, started chasing a ground from the brown wire on the solenoid. Seemed that was sending power to ground. Have gotten as far as the ignition switch and the white wires there go to ground. Not suppose to and since there are three of them bundled together, I'll have to separate them to see which one is grounded. Hopefully. I'll keep everyone posted as I go along. And this all started because my throttle was not retracting and I wanted to remove the air filter to make sure the throttle plate was closing. Guess I'll get to that sometime.

Well Randall is a good mechanic; I am not sure where this other forum is, but Randall should respond over there, maybe, plus he might know something we do not about this problem. I have done the exact same thing, but did not get a problem. CJD is good mechanic also, but I would change out the solenoid because it seems to me you hit the case of it and the originals are still confusing to me. Do you have an extra? Anyway what exactly is the problem again; the ignition will not light up? Or the starter button does not work? Or there is smoke coming out?
steve

John, you were absolutely right and I had a hard time believing it. But, almost as a last resort, I decided to follow your advice; however, I took the easy way out. I only removed and cleaned the ground above the battery. A lot easier to get to. When I hooked everything back up, presto, it is all working again. Thanks! And I won't be so skeptical the next time.

Bob

No sweat...just glad it was an easy one! If you can't tell, I've shorted wrenches hundreds of times, so have plenty of experience in that sort of self induced failure.