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Wedge lucas wire nightmare

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flyintr7

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Hello all , I have hit a snag with my rebuild on a 1980 TR7 convert . I should say another snag as this has been a five year project . I purchased the car for $400.00 from a guy who had it on jack stands in his garage . It was not running and missing a wire harness for the engine . The last time it was registered was 2001 , after rebuilding the original engine only to have a blown head I decided on a v6 conversion . I did the Johns cars conversion and was a good bolt on kit . So after rebuilding the 1978 Buick 231 bored 30 over , medium cam , headers I dropped it in. The car fired right up and purred like a kitten , give or take a few decibels . I finally got my new drive shaft , so I installed it replaced the brakes , and was ready to set it back on the ground . Checked one last time for fire up and nothing ... no power to anything inside the car . I've got power to the starter , alternator , and that's about it . I tried a suggestion of jumping a battery to the cig lighter and the headlights pop up and my clock worked . I have tried to jump off the small wire on the starter right to the battery and the lights will activate but only if the key is turned to start . So all I did from having a running car to a no power issue was brakes and driveshaft . I was wondering about starter relay , or ignition switch but then I think my clock would not be wired thru these so I still sit here wondering what o look at next . Anyone have any ideas ? I just pulled the dash back out of it and will recheck for loose or broken ground wires but help would be appreciated . Thanks in advance . Rick
 
Check the fuse box. A very common issue is bad connections on the fuses. It may look OK but be a problem. Also the grounds near the battery.
 
Thanks for the reply George , I have pulled the fuse box and cleaned it with electrical cleaner and checked for loose connections , also I removed the grounded wires by the wiper motor , cleaned the area scuffed down to bare metal . Still nothing . I took a reading from the alternator and did not have voltage to one of the terminals so I am going to trace that wire back , so far it goes to a brown and yellow wire that enters under the dash and heads back out into the engine compartment . I was wondering if this is just a ground to chassis wire if I can splice it to the chassis to see if it helps . I guess this is the only bad part of doing a conversion as now the engine harness is for the Buick engine and the change back to Triumph is one where it needs to be done one wire at a time .
I did have a quick issue with something like this when I was just starting it as a project and it seemed to be the headlight fuse that was loose and just by touching it the car took off. Its just strange as I was not working anywhere near the fuse box when I lost everything .
Again thanks for your input , I will double check everything on Tuesday evening as work and bowling are on tap for today . I should probably just wait until I get the Holly four barrel intake and carb that I purchased and do everything at one time . I am really excited to see what 205 HP will do with this little car !!
 
Does it still have the inertia switch?
 
If it was part of the engine harness I would say it does not . When I purchased the car there was no harness in it for the engine . It was running fine until I put brake pads on it . That is the kicker , fifteen minute brake job and now this ... guess that is why there are so few of them around !
 
Not sure if the 7 had an inertia switch
Look up at the corner of the bonnet opening by the bake booster.
A little square thing on a bracket
 
DNK said:
Not sure if the 7 had an inertia switch
Look up at the corner of the bonnet opening by the bake booster.
A little square thing on a bracket
Click to expand...

Only an FI TR7. Carb TR7s used a mechanical fuel pump. Some of them were cylindrical.
 
Remembered the cylindrical thing
But took a stab in the dark at it
 
Looks like it is the main power feed wire from the alternator . I'll try and replace it on Thursday , she came to life by jumping power to the ignition switch brown wire . Now it's just a matter of back checking that wire .
 
I feel your pain! We got a John's Cars TR7 for my 16 year old daughter. She is driving it to school today in fact. It has electrical gremlins as well. Looking at the wiring harness as I was installing new fog lights I found odd splices that didn't seem to make any sense, probably done by the person who installed the V6. I ended up wiring the fog lights to an aftermarket switch to keep it simple. Every time i would apply power to the wire that was supposed to go to the fog lights(RY), the heater fan would come on!
 
Clay did a nice pictorial on redoing that.
Don't know if the wiring is the same for your 6 though.
 
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