No spark in SV...

[SRQJeff]

Hey, folks. I'm stumped again, hoping someone can help. I'm not getting any spark for some unknown reason. As far as I can tell, I'm supposed to be getting power to the coil from the wire that runs from the bottom of the solenoid switch, along the firewall, and to the positive terminal on the coil. No juice, though. The wiring diagram makes it look like the power should be coming from the ignition switch, but mine isn't wired that way (and neither is the parts car in the back yard). Bad solenoid switch possibly? It cranks over nicely, but it could be something wrong with that lower connection, I guess. Anyway, for your kind consideration I offer something I ran into recently: an official 48-page Lucas fault diagnosis manual. Just go to www.jkeckert.com/freedownloads/LucasFaultManual.pdf. It shows a direct connection from the coil to the iggy switch, too, so it didn't do me much good.

 

[sunbby]

That wire from the solenoid, that runs acros the firewall, only provides 12 volts while actually cranking. It is used to bypass the coil resistor when starting. There should be 12 volt from the ignition switch which comes under the dash an out into the engine bay on the passenger side.

In this photo you can see the white-green white (from the solenoid) connected directly to the coil. Then you can see the solid white wire that comes from the wire bundle containing the right side headlight and blinker wire, connected to the ballast resistor and a short solid white wire from the resistor to the coil.

 

[Derek]

Jeff, I hope you are better than I am but I had this happen to me once on my 67 SV it cranked over but no start, turned out that the lead from the coil to the dizzy was not pushed in, my mess up as I had the whole thing apart...sometimes you just have to go back to the basics, felt pretty stupid when I figured it out.

Derek

 

[SRQJeff]

Aha!

Ah, that makes sense. Thanks. I knew the resistor was to reduce the voltage, but it thought it was providing a high-impedance path to ground or something like that. I should have figured it was the elusive line from the switch. I swapped out the coil for a spare one, as the spare coil's secondary reads about 2k lower resistance. No change, though. I'm getting juice to the points but nothing to the plugs. It may be something as bone-headed as a wire not shoved in far enough, but I have checked for that. Maybe it's time to pick up an electronic ignition and forget about points.

 

[Ron67Alpine]

how's the condenser?

 

[Faux tgr 66]

On the first 2 '67 SV's I owned I had similiar problems and it turned out to be the engine ground wire.

 

[RootesRich]

If you are absolutely sure you have voltage at the points then I'd suspect you have a bad distributor cap or rotor.

 

[beamdream]

how's the condenser?

Are you sure the points are opening and closing as the distributor rotates ? or have you possibly grounded the points by disturbing an insulated washer ?

 

[Tom H]

I'm getting juice to the points but nothing to the plugs

Hmmm. How do you know this? If you are measuring the voltage at the points and you see 12 V and it stays at 12 V, then the points are staying open or the ground path from the points to ground is open. The voltage at the points should be alternating between 12V and zero V as the points open and close as the crank turns.

Tom

 

[agmason54]

Nosparkem

Based on my own miserable experience these are the usual suspects I would guess based on what you say

Condenser
Cap
Rotor
My last breakdown turned out to be the rotor.I had a hard time believing some thing so simple could totally fail. I alway keep a complete known running distributor and coil in the trunk.It's the only way to get home. A new electronic ignition is no cure for a bad cap& rotor.
good luck
agm

 

[SRQJeff]

Still working on spark

The cap, rotor, condenser, and wires are all new. I measure close to 3 kohms resistance in the wire from the coil to distributor cap, but I think that's normal. The shorted out points sounds like a good possibility. When I pry open the points and put the ohmmeter between them, it shows a short. I'll check out that concept. Thanks.

 

[puff4]

My last breakdown turned out to be the rotor.I had a hard time believing some thing so simple could totally fail...

Actually, there has been a *huge* load of new defective rotors on the market for the past 10 years or so. The design was flawed, and it's a known problem. Some of them even came in Lucas boxes.

Failing style of rotor:

See: http://www.theukmotorsports.com/2011/11/british-car-rotor-button-tech-tip

Does your rotor button look like this? Is the contact held onto the plastic with a rivet? If so, you may experience a misfire or ignition failure. The original Lucas rotor contacts were recessed into the plastic and did not use a rivet. On these rivet designs, the bottom of the rivet ends up being very close to the spring clip on the underside of the rotor, which means there is insufficient insulation between the contact and the distributor shaft. Electricity follows the path of least resistance, which in this particular case means it grounds out through the rivet on to the spring clip and then to the distributor shaft, all of which means no spark to your plugs. We replace these when we come across them to avoid ignition problems. If you’re having ignition problems, this is a good item to put on the checklist.

...and here: http://www.distributordoctor.com/rotor_arms.html

Recently manufactured rotor arms have been failing because the typical "mix" used in the injection moulding nowadays contains more carbon blacking and is therefore more conductive. Still more importantly, the rivet which holds the brass inlay into the moulding is slightly longer than the original, bringing it too close to the spring clip on the underside. The high tension current, averaging 30,000 volts, is always looking for the easiest route to earth and shorts out from the tip of the overlength rivet, through the reduced thickness of more conductive plastic and the spring clip on the underside of the rotor arm, to earth out down the distributor shaft. Result - no sparks at the plugs. The situation sometimes rectifies itself on cooling, but then reoccurs with increasing frequency until the rotor permanently short circuits.

SO... get your rotor arms here and they won't fail:

http://www.distributordoctor.com/red-rotor-arms.html

 

[RootesRooter]

All new parts? Any chance the plug wires are installed 180 degrees off on the cap? Also, could the insulator on the new points be mis-installed and grounding out?

How about the little cloth-covered wire in the dizzy? They break over time. If you're down to just a strand or two of wire, it may not be enough to fire.

 

[SRQJeff]

Yee, hah!

Thanks to all. I'm finally getting a nice white spark. I don't really know what I did except take it all apart, clean the contacts, and put it back together. Maybe tomorrow I'll put in some gas and see if she's ready to come out of the decade-long slumber.

In terms of ignition parts, I've used the following in the past with no problems (except for this recent one):

Points: AC Delco E192
Distributor cap: AC Delco E378D
Condenser: AC Delco E255A
Plug wires: Beck Arnley 175-2815, Borg Warner Sure-Spark CH624SP (for 6-cyl., but four of them fit)
Plugs: Autolite 63

Thanks again. I'm aiming to take my wife for a ride on her birthday, April 24. With no interior yet, it'll be a challenge. But then again, I didn't say how long a ride.

 

[Ken Ellis]

Jeff's username is now "Sparky."

Sometimes a bad connection is revealed by fiddling with the wires. Although it may happen again, at least you know what's there actually works.

In my younger, foolish days, I've offered a passenger a nice low beach chair in lieu of an actual seat. I recommend the real interior...

 

[puff4]

A common problem is to not correctly stack the washers on top of the pints spring, shorting them to ground. I wonder if that's what happened here? :/