[pclackett]

Hi
Sorry if i am startign a new thread where I have already talked about my silver shadow 2 starting problem, but i cant find the old thread.
So, in summary, i have cured a carb float chamber leak by servicing/replacing both flot chambers, needles etc.
Now I can't get the car to start. There is fuel reaching the float chambers. I can hear the fuel pump priming when I did a check today - fuses all ok, no spark evident when I took out a plug lead, inserted copper wire, put other end of wire to an earth.
Did usual check on distributor cap - looks clean, no arcing, rotor arm looks ok, Ht leads all look connected etc. A new condensor was put in a few years ago.
Still just turning over but not starting. This is frustrating, i must be missing somehting really simple, and advice appreciated

 

[Wraithman]

Place a test lamp on coil neg terminal to earth. Does it flash?

 

[pclackett]

ok - or i might do a reading with my multimetre -best to run it from the negative terminal?

 

[Wraithman]

Yes , neg term.

 

[Jim Walters]

A 12 volt test lamp will work better than a multimeter due to the speed of the flashes and reaction time of the meter. Here are some instructions I have posted previously to narrow down ignition faults:


First thing to do is to check for spark at a plug lead, then spark at coil lead. If no spark at plug but spark at coil lead - rotor is faulty. If no spark at plug and no spark at plug lead - coil or module faulty. To determine which, attach a 12 volt test light to negative low tension terminal of coil. Have someone crank over the engine, if light flashes quickly the module is working trying to fire the coil - coil is faulty. If light doesn't flash the ignition module is faulty. These tests are assuming you have confirmed there is power at the positive low tension terminal of the coil.
Also to confirm a rotor is faulty, remove cap, remove coil lead from cap, hold end of coil lead to within an eighth inch of the centre of the rotor with gloves or insulated pliers. Have someone crank over the engine. If the sparks jump to the centre of the rotor the rotor is faulty. A spark SHOULD NOT jump to the rotor if it is good. Rotors can function fine when cold, short out when hot, and have intermittent symptoms. We see faulty rotors fairly often, especially aftermarket ones.
You need to post a picture of your ignition module to determine which type it is. Stock was the Lucas Opus, they do fail with age. The above test will narrow it down. If it has been replaced with a Crane ignition module, they would burn out if the key was left on too long without the engine running. Using too hot of a coil with the stock Lucas cap and rotor can cause flashover in the cap and misfiring.

If you can't find a post you have previously posted just hover the cursor over your name and click on "discussions created", in your case that will be 3, click on that number and all your previous posts will appear. If you want to find a discussion you have replied to that someone else started, click on "replies".

 

[pclackett]

Place a test lamp on coil neg terminal to earth. Does it flash?

ps coil isnt showing any life - is it ok to just buy a standard 12 v lucas coil - with or without ballast? thanks for your help

 

[Wraithman]

FYI The Opus ignition which is known to suddenly, triggers the coil. Although a known second coil for test purposes is good practice, you may want to focus on the Opus within the distributor.
Buy a standard coil. Your ballast is separate within the system.

 

[pclackett]

many thanks for all this splendid advice, appreciated
patrick

 

[pclackett]

Dear both
thanks for your advice - i think i have solved it. I substituted one of my spare 12v coils - and got spark at plug lead then got the engine turning over! Need to order a new 12 coil and problem solved. Old coil looks very aged and it is in a hard to access bracket but that will just be a fiddle..
thanks guys