Gday im a new member to this forum.I am also a new jaguar owner of about 1 week,I have a problem with no spark from the HT (High Tension)lead however i have a fully charged battery and get the ignition light i can also crank the engine.I have checked That power is getting to the coil,(used a lightbulb and wire from the (+) terminal on the coil to Ground and the lightbulb came on,when the ignition is on).I have also replaced the points and checked that when they are closed the LT (Low Tension)circuit is complete and when they are open the LT circuit is broken,IE used the lightbulb test,When the points are closed the lightbulb comes on and when the points are open the lightbulb dosnt come on.Also I have run a new wire from the battery (+) to the (+) terminal on the coil (same result).I have tried another coil aswell with same result.I even disconnected the condenser (still had the same result) The only response i have seen from either coil is a single spark when i turn the ignition back off again.

If anybody knows what might be causing this problem any help would be most appreciated thank you. A Very Confused Mechanic

Submitted by cyber_mad@hotm… on Thu, 01/15/2004 - 18:01

I Own A 1974 XJ6 4.2 Saloon Series 2

Thanks steve you are absolutely correct if the car was running before you do any work on it and not working after the chances are you have done something wrong.
And i am quite familiar with the saying "If it aint broke dont fix it".
Unfortunately it had ceased running before i had started work on it so i wasnt completely sure it was something i had done(thinking the points were responsible for it not starting).

Thanks for you advice have a good day.

Submitted by NE52-32043 on Thu, 01/15/2004 - 13:37

There's an old rule that I've been introduced to many times over the years -- If it was working before you fixed it, and now it's not, the first place to look is what you did. So you won't feel too bad, two years ago, I changed the oil and filter on my '72, V-12. After doing it, I started the engine and this horrible squeaking noise was coming from the front of the engine. I poked and prodded, found nothing. Took it to a mechanic who diagnosed it as a bad water pump. If not that, he said, then it's probably the timing chain tensioner, which probably meant an engine rebuild.

I pulled the water pump, had it rebuilt, checked everything, put it all back together, and the noise was still there. Not wanting to pay for an engine rebuild, I left the car sitting. Told the story to a fellow JCNA member, Bruce Cunningham, who was visiting. Bruce took a piece of hose, listened to my squeaking, squeeling engine, asked for a screw driver, and in a few seconds, no more squeeling.

The problem? When I was struggling to get the oil filter housing back in place, I hit the timing bracket under the crankshaft damper and bent it. It was touching the damper and causing the squeak. Bruce bent it back, no more squeak. If something is broke after you fixed it, look at what you fixed, Bruce said -- it's probably something you did, not something new. I knew that, but hadn't seen the obvious. I rationalized that my 30 year old car probably needed a pump rebuild anyway, but would have been nice to have not had to do the work.

Glad you solved the problem and that you're back up and running!

Steve Weinstein, JTC-NJ
'72 E-type 2+2
'70 XKE FHC

Submitted by cyber_mad@hotm… on Wed, 01/14/2004 - 19:39

I Own A 1974 XJ6 4.2 Saloon Series 2

Ok everybody i have found the problem and is fixed now thanks for all your help,i guess its time to take my lumps and tell ya what i did wrong.
It was my fault i did a simple little thing wrong i had put the condensor lead and the points lead on top of the insulator instead of under the insulator meaning it wasnt completing the circuit........DOH.

Feeling Stupid Now.
Again thank you for all of your help it was appreciated.

Submitted by cyber_mad@hotm… on Wed, 01/14/2004 - 19:37

I Own A 1974 XJ6 4.2 Saloon Series 2

Ok everybody i have found the problem and is fixed now thanks for all your help,i guess its time to take my lumps and tell ya what i did wrong.
It was my fault i did a simple little thing wrong i had put the condensor lead and the points lead on top of the insulator instead of under the insulator meaning it wasnt completing the circuit........DOH.

Feeling Stupid Now.
Again thank you for all of your help it was appreciated.

Submitted by cyber_mad@hotm… on Wed, 01/14/2004 - 05:40

I Own A 1974 XJ6 4.2 Saloon Series 2

Thanks for your response Stew.
No ive not replaced the cap and rotor as they were working.
when i first had problems was after i had started the car it stalled about 20 seconds later and hasnt fired again since let alone run,(Tried to start it for about 5 mins afterwards ( wouldnt fire at all).Thats when i replaced the points which were shot (badly pitted)the condensor and coil After doing every test i could think of.Still no spark from High Tension Lead (so that rules out rotor and dizzy cap)which is why i have been checking the HT lead for a spark.

Any help is appreciated thank you.

Submitted by cleavefamily@c… on Wed, 01/14/2004 - 02:51

I assume you replaced the cap and the rotor and both were from the same manufacturer. I once got real cheap and only replaced the rotor and found that it wasn't compatible with the cap after trying just about everything else to figure why I didn't have spark at the plugs. One time, I forgot to put the rotor back on. I trust the distributor shaft isn't loose vertically? The last time I did this type of thing I rebuit the whole distributor and found that it is so much easier to adjust everything and check operation when the distributor is removed from the car. I also have back problems.

Stew Cleave
JOCO Chief Judge
'69 E-Type 2+2 and other LBC's

Submitted by cyber_mad@hotm… on Tue, 01/13/2004 - 19:49

I Own A 1974 XJ6 4.2 Saloon Series 2

Gday Whunter no it dosnt offend me at all and yes i have replaced points in many cars before and have also rebuilt engines, i do most of the mechanical work on my cars and usually dont have this type of problem.There isnt that much to replacing points in a dizzy i think i would have difficulty messing it up :)
Anything else you can think of?.

Again all help is appreciated.

Submitted by cyber_mad@hotm… on Tue, 01/13/2004 - 18:58

I Own A 1974 XJ6 4.2 Saloon Series 2

Yes sorry i meant the Points had been gapped to .016 inch (.4mm).I have replaced the condensor (same result) no spark from high tension lead except when i back off the ignition i then get a single spark.
voltage reading from the battery was 12 volts and from the coil + terminal was getting 6 volts, so i checked the balast resistor it was reading 10 volts on the incoming pole and 6 volts on the outgoing pole so i then removed the balast resistor from the equation by bridging it, i then was getting 10 volts to the coil but with the same result.
Could the ignition relay be responsible ?.
I cannot think of anything else it might be.
Looks like I might have to get the auto sparky in.

Thank you for you help it is appreciated.

Submitted by cyber_mad@hotm… on Tue, 01/13/2004 - 02:05

I Own A 1974 XJ6 4.2 Saloon Series 2

Thank you Mike & Whunter For your Advice.

I had checked to see if the ground wire was earthing out on the points already but no it wasnt.I have also been cranking the engine with Dizzy cap off(had help) rotor button was revovling np.The points had been gapped at .016mm Brand new set.And i had also Brindged the Balast resistor,to remove it from the equation.
Sorry i dont have a digital camera yet to give you a picture.

Again all Help is Appreciated :)

Submitted by asemastermecha… on Tue, 01/13/2004 - 01:28

Hello Mike
With the distributor cap off; get someone to crank the engine.
Need to verify that the rotor is turning.
Could you send me a digital picture of the distributor without cap or rotor.
This sounds similar to a personal car 23 years ago, full tune-up and no spark, turned out the new rotor was bad, arcing to ground

whunter
ASE Master Mechanic
http://www.woodwardauto.com
asemastermechanicatjuno.com

Submitted by mfrank@westnet.com on Tue, 01/13/2004 - 01:19

There are only a few things that can cause this. It may be that the ground wire is fouling your points. The gap could be improperly adjusted. Point resistance could be high. Bad condenser. Bad coil. Finally, if you have a ballast resistor, the resistor may be open (do you have power to the coil while cranking?). That's the list.

Mike Frank

Submitted by cyber_mad@hotm… on Tue, 01/13/2004 - 00:42

I Own A 1974 XJ6 4.2 Saloon series 2

Well i put a new condensor into it and seems to be exactly the same so it must be something else,However what that is i have no idea.Is there anything else you can think of that might be responsible.

Any help ia appreciated thanks.