pipercollins
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This will be a more or less familiar story to many of you...a wicked combination of Lucas electrics and previous owner muddling.
So Monday evening was the monthly British Motoring Club cruise night. I hadn't been real regular at club meetings for the last year or two (house renovation). But I'd had a little more time recently to tweak some things with the 1976 1500. I had the carb tuned up and did some suspension work and everything had been running pretty good. The weather was perfect, so I was looking forward to the drive.
The group took off with 10 or 12 cars and all is well, until 10 minutes into the scenic cruise, the Spit dies. I see the tach go to zero. I'm rolling down a hill at this point, in the middle of our pack. So I down shift and pop the clutch. The engine whines while I keep slowing down, but it doesn't catch. No ignition. I roll around the corner through a busy intersection and wheel over to the side of the road. A couple of the other club members stop with me while everyone else goes on.
We pop the hood and look around. All the connections look good. Distributor, plugs, and wires are all about a year old. I'd had a similar symptom earlier in the spring and had to replace the cable from the battery to the starter solenoid...that was definitely good now. Nothing obvious, but it's definitely no ignition. Now, the PO had installed a Jacobs ignition control computer. A little blue box mounted to the frame, supposed to "condition" the spark. I've always been skeptical of its value, but I hadn't gotten around to the very involved job of rewiring everythign to eliminate it. It does change the wiring between the coil, the distributor, and the drive resistor. It also incorporated a switch in-line in the computer's wiring harness so you can run it on "computer" or "conv ignition". (I've run it both ways, never noticing a difference...)
That switch always makes people scratch their heads, but it's always worked. Till now, anyway. One of the other guys fiddled with the switch while I tried to start the car. We actually got it to fire a couple of times, but couldn't get it to keep going. So it seemed to me that switch was the culprit. Of course, parked alongside the road in fading daylight, one looks for direction and reassurance. My buddies seemed to agree with me, but very noncommitally. Fair enough. My car. It's up to me. Fortunately, I've owned a Triumph long enough to know what to keep in the boot. Wire pliers, connectors, and a reel of jumper wire, among other things. Unfortunately, the ignition computer invalidated the laminated wiring diagram.
OK. Man of action. Disconnect the battery (thank you, quick disconnect). Take a deep breath. Cut the switch out. Reconnect all four wires straight, eliminating the switch. Reconnect the batter (thank you, quick disconnect). Start the car (it fired up immediately). Back on the road in about 12 minutes. Everyone else beat us to the pub, but we got there before the first round of drinks. I was briefly embarrassed, but my street cred (literally) remained intact. Not bad for a Monday.
I got home fine and everything, but now I'm left wondering how best to make my quick fix permanent. I'm inclined to go ahead and eliminate the ignition computer, but that means some pretty involved rewiring. I'll post more as I sort through it, but does anyone have any from-the-hip insights on original ignition configurations vs. ignition computers and "spark conditioning"?
Regards all,
Bill
So Monday evening was the monthly British Motoring Club cruise night. I hadn't been real regular at club meetings for the last year or two (house renovation). But I'd had a little more time recently to tweak some things with the 1976 1500. I had the carb tuned up and did some suspension work and everything had been running pretty good. The weather was perfect, so I was looking forward to the drive.
The group took off with 10 or 12 cars and all is well, until 10 minutes into the scenic cruise, the Spit dies. I see the tach go to zero. I'm rolling down a hill at this point, in the middle of our pack. So I down shift and pop the clutch. The engine whines while I keep slowing down, but it doesn't catch. No ignition. I roll around the corner through a busy intersection and wheel over to the side of the road. A couple of the other club members stop with me while everyone else goes on.
We pop the hood and look around. All the connections look good. Distributor, plugs, and wires are all about a year old. I'd had a similar symptom earlier in the spring and had to replace the cable from the battery to the starter solenoid...that was definitely good now. Nothing obvious, but it's definitely no ignition. Now, the PO had installed a Jacobs ignition control computer. A little blue box mounted to the frame, supposed to "condition" the spark. I've always been skeptical of its value, but I hadn't gotten around to the very involved job of rewiring everythign to eliminate it. It does change the wiring between the coil, the distributor, and the drive resistor. It also incorporated a switch in-line in the computer's wiring harness so you can run it on "computer" or "conv ignition". (I've run it both ways, never noticing a difference...)
That switch always makes people scratch their heads, but it's always worked. Till now, anyway. One of the other guys fiddled with the switch while I tried to start the car. We actually got it to fire a couple of times, but couldn't get it to keep going. So it seemed to me that switch was the culprit. Of course, parked alongside the road in fading daylight, one looks for direction and reassurance. My buddies seemed to agree with me, but very noncommitally. Fair enough. My car. It's up to me. Fortunately, I've owned a Triumph long enough to know what to keep in the boot. Wire pliers, connectors, and a reel of jumper wire, among other things. Unfortunately, the ignition computer invalidated the laminated wiring diagram.
OK. Man of action. Disconnect the battery (thank you, quick disconnect). Take a deep breath. Cut the switch out. Reconnect all four wires straight, eliminating the switch. Reconnect the batter (thank you, quick disconnect). Start the car (it fired up immediately). Back on the road in about 12 minutes. Everyone else beat us to the pub, but we got there before the first round of drinks. I was briefly embarrassed, but my street cred (literally) remained intact. Not bad for a Monday.
I got home fine and everything, but now I'm left wondering how best to make my quick fix permanent. I'm inclined to go ahead and eliminate the ignition computer, but that means some pretty involved rewiring. I'll post more as I sort through it, but does anyone have any from-the-hip insights on original ignition configurations vs. ignition computers and "spark conditioning"?
Regards all,
Bill