When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Hello, please help. On my XJ12 S2 I have a Lucas Opus ignition system. It happens that sometimes I have a spark on cylinder 3B and sometimes I don’t. The spark plug is fine, the cable is good, I watched the switch arm and the ring under the arm looks fine.
Hello, please help. On my XJ12 S2 I have a Lucas Opus ignition system. It happens that sometimes I have a spark on cylinder 3B and sometimes I don’t. The spark plug is fine, the cable is good, I watched the switch arm and the ring under the arm looks fine.
[QUOTE = Greg u Francuskoj; 2451912] Kako ste saznali da je 3B? [/QUOTE]
I simply have a tool like this. I put it directly in the cap where the 3B cylinder cable goes and only it has no spark. And that spark plug is constantly black and damp from fuel.
The Opus system has a "Plastic" wheel under the rotor. This "wheel" has 12 ferrite inserts it. As each "insert
passes the pick up, spark in generated.
These "Inserts" fall out, gravity. They also fall out in SMALL pieces, thus reducing the inductive capacity of the wheel at that particular cylinder.
We would apply some "glue" to the underside of each slot, to stop gravity stealing these inserts.
I have a wheel in the shed, somewhere, and I think? it has 11 inserts, and many loose ones. That car was the last I fitted a Crane Ignition System to a very long time ago.
Since yours is a sometimes issue, I suspect that the Insert related to 3B is missing some of its product.
Hello, I have an Opus AB 3 on the car and it happens that there is no spark on the 3B cylinder, I noticed that the resistance of the coil is not good, I have 2 ohms and it should be 0.8-1 ohms. When I connect 12 to the + contact on the coil, I get a spark on that cylinder. I removed the wire coming from the Resistor to the + connector on the coil and I see it works that way. I'm wondering if I can connect via a relay to get 12 volts when the key is turned.? I also bought another coil that has a special resistor, can I connect it?
That removing wire is replacing the trigger mechanism of the Ign System, and thus will always create a spark if the rotor is pointing at that post of the cap.
As I mentioned in your similar earlier thread, the plastic wheel possibly has a dead, or dying, ferrite segment in 3B position.
The Amp, Coil, Wires Etc have NO idea which cylinder is being fired, that is purely the Plastic wheel and ferrite segments, triggering the coil to actually spark. The supplied is then sent from the coil, to the cap, then the rotor, and then the distributor does exactly as its name defines, "distributes the spark".
The coil on the PreHE, Carby or Injected, is a 1.2 +/- Ohm Contact Points Resistor Spec coil, nothing fancy be any means.
Not sure of the relay, but doubt it would do anything at all.
The fact, as also mentioned, this is at 3B, and intermittent, tells me, from experience, the Ferrite Segment MAY, repeat, MAY be the root cause. After that is verified, good or bad, then other components within the distributor come into the discussion, and the only other items are the Rotor, which appears to be OK. A badly arced 3B post inside the distributor cap could?? be having some affect.A hair crack in the cap at that post, yes pf course.
The plastic wheel looks right to me, all 12 bars are in place. I still don’t understand what happens when I put more voltage on the coil and it works.
OK, I will go with that for now.
The coil is basically a 6Volt coil, run through the ballast at about 7V. There is a provision inside that Ballast Block for a 12v By-Pass to basically "shock" the coil to aid starting. This is tolerated by the coil for those short bursts.
Not sure of your market, but all my PreHE ran/run a Bosch GT40R oil filled coil. The "R" being the designation for resistor.
The dropping of spark at 3B only is weird if not;
Ferrite segment failed
Cap issues at that post. Crack, old age.
Rotor very old, and not passing that 3B post close enough to jump the spark consistently.
Another question. Is the spark generated a FAT BLUE cracker of a spark, of a weaker yellowish spark.? Test lights wont help here. Plug any oldspark plug into 3B lead, lay that plug on the engine, thus earthing the casing, and observe the spark intensity.
The coil, Amp, etc, can ONLY generate a spark when a Ferrite segment passes the pick up coil, so with 3B the only post that is an issue, I still return to that wheel. Of the many I have owned, maintained, over very many years, that wheel is the major issue 98% of the time for a single cylinder spark loss. Removing that wheel to examine the underside segment integrity MUST be done with GREAT CARE, as it is old now, and will chatter in less than a heartbeat.
That removing wire is replacing the trigger mechanism of the Ign System, and thus will always create a spark if the rotor is pointing at that post of the cap.
As I mentioned in your similar earlier thread, the plastic wheel possibly has a dead, or dying, ferrite segment in 3B position.
The Amp, Coil, Wires Etc have NO idea which cylinder is being fired, that is purely the Plastic wheel and ferrite segments, triggering the coil to actually spark. The supplied is then sent from the coil, to the cap, then the rotor, and then the distributor does exactly as its name defines, "distributes the spark".
The coil on the PreHE, Carby or Injected, is a 1.2 +/- Ohm Contact Points Resistor Spec coil, nothing fancy be any means.
Not sure of the relay, but doubt it would do anything at all.
The fact, as also mentioned, this is at 3B, and intermittent, tells me, from experience, the Ferrite Segment MAY, repeat, MAY be the root cause. After that is verified, good or bad, then other components within the distributor come into the discussion, and the only other items are the Rotor, which appears to be OK. A badly arced 3B post inside the distributor cap could?? be having some affect.A hair crack in the cap at that post, yes pf course.
I posted a video showing all 12 rods responding to a magnet. In the second video you see what happens when I put + 12v on the ignition coil. I just wake him up and he works. Sometimes it works while driving, and sometimes it doesn’t
The fact this "fault" is only at 3B is the thing I dont get with what you are saying/showing.
The ONLY items that will"killl" a spark from a specific post of any distributor cap are:
The rotor.
The coil trigger, in this case the Ferrite Rods.
The cap.
Everything else on any Distributor spec system will affect the whole system at random.
The coil simply fires a spark as messaged by the Pick Up, which is activated by the Ferrite Rods. The amp is also just doing what it is told. These things have NO idea which cylinder is being sparked.
There may be a voltage drop out. NOTHING to do with 3B at all.
Ignition switch electrical section, WELL documented as reeking havoc due to old age. Easily cleaned up and returned to reliable service.
The Ballast Block, on the throttle capstan pedestal. They were always a problem. NOTHING to do with 3B at all.
We replaced hundreds of them back in the day. All mine run the Crane XR System, and that Block is deleted. Other things need altering, it is NOT a plug and play.
Some specific section of the OE system. ?Ballast Block, etc. The OE is spread over many pages from memory, and I have NOT scanned all of them, and no longer have a scanner.
No spark for cylinder 3B
