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battery relocation disaster


ianD
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So I relocated the battery to the trunk this weekened and did the following. Grounded the battery at the rear seatbelt bolt, ran the positive to a generic distribution block in the engine bay and ran all the wires that used to connect to the positive terminal to the distribution block. After everything was hooked up before I started it I remembered I hadn't connected the wire to the starter. As soon as there was a solid connection the starter started smoking and cranking the engine but the key was in the off position and smoke was pooring from under the rear of the car (assuming from the battery ground?). I immediately unhooked the battery and let the smoke clear and found the started wire was extremely hot but not the distribution block and the dist. block was not accidentaly grounded, no wires appeared to be fried but I didn't do a thorough inspection. The only thing I can think of is I didn't ground the engine block to the frame/body and therefore the starter wasn't grounded. Don't know if that would make a difference but I'm no wiz with electrical and everything else is hooked up exactly as it was before. Could there be ground somewhere there shouldn't? Could I have fried the starter or any other components? Any help would be greatly appreciated, I don't want to burn my car to the ground.

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Sounds llike you have the correct diagnosis, you didn't ground the block. Buy a new 24" battery cable at your local auto parts store, & attach to drivers side of block where the original ground strap is, attach other end to the body where the strut bearing mounts with 3 bolts. Scrape the paint under the nut where you bolt it to the body, put a lockwasher or at least loctite on there.

As far as smoke under the car, it was trying to source a ground through the block/tranny & complete wiring harness where ever it could. If it only smoked for a few seconds, you probably didn't burn through any insulation on any wire. If it was any longer than a few seconds, you may have melted through insulation somewhere on a wire.

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Agree that the engine block must have a nice big ground cable, but that is not your big problem. The starter found a ground, but probably not a great ground and hence the smoke. The fact that the starter ran is the bigger issue. My guess is that you connected the + to the wrong terminal on the starter solenoid. The solenoid is a big switch, the terminal closest to the motor is directly connected to the motor, the other terminal should be connected to the battery. If you connected ti to the wrong terminal, you bypassed the switch and drove the starter continuously. If it was connected correctly, the small terminal that energizes the solenoid is shorted to + somewhere.

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This is what you need to Read!!!!!!!

Agree that the engine block must have a nice big ground cable, but that is not your big problem. The starter found a ground, but probably not a great ground and hence the smoke. The fact that the starter ran is the bigger issue. My guess is that you connected the + to the wrong terminal on the starter solenoid. The solenoid is a big switch, the terminal closest to the motor is directly connected to the motor, the other terminal should be connected to the battery. If you connected ti to the wrong terminal, you bypassed the switch and drove the starter continuously. If it was connected correctly, the small terminal that energizes the solenoid is shorted to + somewhere.
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Looked into it last night, the wire from the battery to the starter solenoid was hooked up correctly and I couldn't see how the other terminal could be grounded. When I tried connecting the ground on the battery with the starter wired up the terminal sparks as soon as it touches the post and you can hear the start click like a dead starter does but when I unhook the starter I can then ground the battery and all is good. Not sure what this means, could the solenoid be bad? As I said I'm no wiz with electrical so any ideas would be great.

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Since you hear the click it sounds that the solenoid is ok. As hrg88 mentioned it feels that the small terminal that activates the starter gets straight + from somewhere. Normally it comes from ignition switch only in start-position.

<<<...the small terminal that energizes the solenoid is shorted to + somewhere.

Sure the solenoid or ignition switch could cause the problem but I doubt it. More likely that you caused it by yourself somehow.

Tommy

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I couldn't see how the other terminal could be grounded.

No

The other terminal should not be connected to anything other than the starter it self. The ground everyone is talking about goes from the chassis to the block. A transmission bolt or motor mount to block bracket is a good spot.

I think the real problem is that you have 12 volts going to the trigger wire. Thats the little wire with a female spade connector on it. Make sure you have the right one going to the starter. it should be 2.5mm black wire.

John

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Fiddled around over the weekend and here's what I came up with. After shuffling around looking for freyd/melted wires I couldn't find much. I had all the wires wrapped in plastic wire loom and where the spring for the throttle linkage pressed on it it had melted through so I guess things got pretty hot but no wires appeared damaged. I hooked the starter and battery up again and no smoke and no continuous starter action occured so I think I when I hooked the thick red wire up to the starter it was touching one of the other posts.

So I started it up and it ran fine but when I went to start it again 15 min later I got nothing. I checked for spark at the plugs and there was none, I checked for spark from the coil HT leed and no spark. Checked resistance across the posts on the coil and it read 4ohm so I think the coils good. Dizzy is a mechanical advance with pertronix type ignitor. Don't know what else to do, any advice?

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Fiddled around over the weekend and here's what I came up with. After shuffling around looking for freyd/melted wires I couldn't find much. I had all the wires wrapped in plastic wire loom and where the spring for the throttle linkage pressed on it it had melted through so I guess things got pretty hot but no wires appeared damaged. I hooked the starter and battery up again and no smoke and no continuous starter action occured so I think I when I hooked the thick red wire up to the starter it was touching one of the other posts.

So I started it up and it ran fine but when I went to start it again 15 min later I got nothing. I checked for spark at the plugs and there was none, I checked for spark from the coil HT leed and no spark. Checked resistance across the posts on the coil and it read 4ohm so I think the coils good. Dizzy is a mechanical advance with pertronix type ignitor. Don't know what else to do, any advice?

Well, the first time when it all went up in smoke, the engine wasn't grounded properly, right? Well, the engine had to have found a ground somewhere to complete the circuit. Did that throttle spring hit a loose wire from that loom? If all the engine's electrons went thru a loose little wire and the spring, then of course those wires are gonna melt off the insulation.

Now, you did get it run, but not for very long. You say those little wires going to the ignition coil look intact, but I don't think they are. The insulation is gone and they've been overheated quite a bit. After running for a little bit they probably crapped out. For fun, I'd first try running a new wire straight from the battery to the positive post on the coil, and see if the car will run and stay running. If so, go ahead and replace at least that wire in the loom with something new permanently, and possibly any other wires that happen to be in the loom.

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Check for 12V at the coil (+). If NG, check the ignition fuse and coil primary wiring.

When you had it off for 15 min, was the key on? If you leave it on with a pertronix, it can continuously feed the coil and burn out the coil or pertronix.

If you have 12V at the coil and disconnect the coil (-) , you can tap the - term to ground and see if you get a spark. If you don't, probably a bad coil. If you do, I would suspect the pertronix.

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