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Help! Won't start

esussman

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Started my BT7 up this AM fine. By the time I was out of the driveway, she grumbled would take any gas and stopped. Won't start back up. Engine cranks fine, pump clicks away. Could it be the pertronix? Was running fine all Spring. Thanks, Eric
 
Replaced rotor. no change. Pulled a spark plug wire. No spark when engine cranks. Guess I'm down to the pertronix or the coil. Any test for the coil or should I swap out the pertonix as I have a spare? Tnx, Eric
 
Replaced rotor. no change. Pulled a spark plug wire. No spark when engine cranks. Guess I'm down to the pertronix or the coil. Any test for the coil or should I swap out the pertonix as I have a spare? Tnx, Eric

Is the pertronix label blistered? That's a sign it's fried. However a bad coil can fry the pertronix and also your replacement pertronix.

I would replace the coil first with a known good coil and only then the pertronix. If it's a gold lucas there have been quite a few bad ones. Bad new condensers are a problem, too. The whole thing is a can of worms. Jeff at Advanced Distributors sells tested condensers, good rotors and Bosch coils. He is convinced going back to points is the way to go.

Another weak point are the rotors with the brass rivet. They split and can stop the car.
 
Hi Eric, just had the same thing happen to me.
1 Check the coil, easy to do in place. Remove all wires, put VOM across the terminals should read 3.5 ohms or greater.
2 If coil OK pull the cap off distributor. The Pertronix has 2 wires going down into the dizzy, one red, one black. With small needle nose pliers pull the red wire up. Mine separated and pulled all the way out due to shorting out somewhere inside the dizzy. Spliced the red wire back together and soldered. This time I used lots of insulation (heat shrink tubing) and replaced back into dizzy. Reconnect the wires to the coil and she fired back up. BTW in my instructions included with the Pertronix is a guide to testing the unit.

Good Luck
 
Thanks Johnny. Coil checks out OK. Pulled on the 2 black wires, one had a solid white stripe. One wire broken. Don't know how that happened. In putting the pertronix back, 2 little screws fell down the dizzy. Am I screwed literally?
 
Thanks Johnny. Coil checks out OK. Pulled on the 2 black wires, one had a solid white stripe. One wire broken. Don't know how that happened. In putting the pertronix back, 2 little screws fell down the dizzy. Am I screwed literally?
Remove the dizzy and shake it. If the screws don't fall out then take the two screws holding the plate on and go in that way. If they fell in, they should fall out.
 
The saga continues. Soldered the connection and covered with shrink tubing, closed up the dizzy. Upon starting I get two mammoth backfires and then stops. I admit to having perhaps foolishly adding some dashpot oil to each of the 3 carbs but actually none is visible in the carb shafts but I did get more resistance when closing them up. Any suggestions? Thanks, Eric
 
The saga continues. Soldered the connection and covered with shrink tubing, closed up the dizzy. Upon starting I get two mammoth backfires and then stops. I admit to having perhaps foolishly adding some dashpot oil to each of the 3 carbs but actually none is visible in the carb shafts but I did get more resistance when closing them up. Any suggestions? Thanks, Eric
Not sure of everything you didm but now it sounds like the Dizzy is 180 out.
 
Not sure of everything you didm but now it sounds like the Dizzy is 180 out.

The backfire indicates your pertronix is still good but your timing is way out. You can't static-time the car with a pertronix in it.

With the car at TDC on cyl #1 (pointer and crank pulley mark lined up, slack in both rockers - or use the balloon device per previous posting) - is the rotor pointed in the general direction of the #1 cylinder? It should be.

Do you have a replacement coil, condenser, points and rotor? If you can rustle that stuff together you can static time the car then re-install your pertronix if desired.

To static time with points: hook up a test light between the distributor connector and ground. Move the car from TDC so that the pointer aligns with a position on the pulley 3/4" up from the TDC notch toward the centerline of the car. Rotate the distributor until the light just goes out. Tighten distributor. The car should now run and you can reinstall your pertronix and time it with a light.

PS - if you attempt to turn the rotor by hand, does it come up against the springs in the dizzy and stop (normal) or does it keep rotating (broken drive pin)?
 
Thanks Steve. Latest is: removed dizzy, cleaned it out. Replaced the pertronix with a new one. Replaced both the rotor and distributor with new ones. Checked gas line. Getting fuel, battery on full charge. Tried to start and the car, turned over very sluggishly, no backfire. Now getting spark. Rotated the dizzy both directions, no change. With the dizzy off the rotor turns normally and car cranks normally. Thought I had the dizzy in backwards. Turned it round 180 degrees, car turned over as normal but constant backire. Thinking now is, I had the dizzy in right all along. Will turn it round again. Perhaps try your idea of installing points and condenser. After 4 hours, went to bed. Very frustrating.

Regards,

Eric
 
Thanks Steve. Latest is: removed dizzy, cleaned it out. Replaced the pertronix with a new one. Replaced both the rotor and distributor with new ones. Checked gas line. Getting fuel, battery on full charge. Tried to start and the car, turned over very sluggishly, no backfire. Now getting spark. Rotated the dizzy both directions, no change. With the dizzy off the rotor turns normally and car cranks normally. Thought I had the dizzy in backwards. Turned it round 180 degrees, car turned over as normal but constant backire. Thinking now is, I had the dizzy in right all along. Will turn it round again. Perhaps try your idea of installing points and condenser. After 4 hours, went to bed. Very frustrating.

Regards,

Eric
I would check the sequence of the plug wires just in case they were removed. I think the order: 1 3 4 2. Look for #1 TDC and go from there.
 
Saga ended. When we replaced the dizzy cap we crossed the position of the wires. Moved them back to the right position, she fired right up. Set the static timing at 7 degrees and all is well. Thanks for all your suggestions. To think this all started with a broken pertronix wire. We made sure this time to allow some slack in the wires near the guts of the pertronix unit to allow movement of the inside plate. Regards, Eric
 
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