Electronic Ignition

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georgecook

Member
My 2000TC is fitted with a 123 Ignition system. Could someone tell me what should happen within the distributor when I suck the vacuum advance pipe from the carb. Should I be able to see movement of the base plate or rotor arm. Currently I can see or hear nothing. georgecook
 
No you won't see or hear anything.

The 123 ignition distributor is all electronic and doesn't have a vac unit like a conventional distributor. The vacuum advance pipe connects to a vacuum sensor inside the distributor, spark advance is done electronically. On the standard unit the vac advance curve and the centrifugal advance curve are selected by means of the setting on the rotary switch. On the 123 tune distributor the centrifugal advance and vac advance curves can be programmed independently with a laptop computer.

If you remove the pipe from the distributor you won't get any vacuum advance. The advance you read off the crankshaft pulley at different rpm's is the selected centrifugal advance.
If you connect the pipe you'll add in the vac advance as well.

Get the model number for the distributor and download the manual from the website http://www.123ignition.nl/

You can then determine the correct ( nearest) rotary position for your car based on the information in your cars workshop manual.

Pat
 
Yup - What pat says ... 123 ignition is a really sophisticated piece of kit that allows you to map ignition curves from a laptop.
 
Thank you gentlemen. This means I am still looking for answers. The engine idles very erratically The timing is fine, the valve clearances are fine, have double checked the carbs for air leaks, the plugs and plug leads are new, and now the distributor appears to be fine. At idle the engine races and finally dies after a few minutes without any input from me. Could it be the coil or have I to have another go at tuning the carb....georgecook
 
I would connect a timing light to the No.1 spark plug lead and watch for wondering on the flywheel. That might point to an issue with the dissy (even electronics can do weird things). Also, does the coil feel warm? I've had coils that would die after a short while of running because of internal shorts, they have felt very warm to the touch.
 
Carried out a compression test a couple of days ago. Numbers one and two cylinders read roughly 175psi.. Numbers 3 and 4 read roughly 165psi each. Am not reading anything into the pressure differences and am assuming these readings are OK.
Will carry out the timing check and report results later this afternoon..georgecook
 
Re fitted the distributor with the intention of carrying out a timing test on number cylinder. Engine was difficult to start and ran very roughly and finally died with a couple of loud backfires.... surely this is a timing problem? Can't understand it....georgecook
 
Have removed the distributor cap and rotor and brought them inside the house to have a good look ( its cold in that garage) The cap looks to be in good condition and is printed on the outside BERU Germany VK105KS .The inside of the cap is very clean with no obvious signs of burning or tracking. I have examined carefully using a magnifying glass ( a quid from poundshop) and yes there could be what seems like a very light scratchmark but it is light in colour as though the cap has been scuffed, there are certainly no signs of burning. IMy good lady has had a look and she can't see any signs of tracking. I really really hope this could be my problem but am not so sure that what I have seen is enough to be the cause.
Is there any suitable way of testing the cap or do I just bite the bullet and order a replacement
 
I really need some help here please.... Since my last post, I feel as though I have done everything that I possibly can but the engine runs the same.
In the last ten days I have removed the cylinder head to check the valves and springs. Replaced the cylinder head gasket and checked tappet clearances. Refitted the carbs and used a sealants well as the rubber "o" rings to hopefully ensure there are no air leaks.. I have removed the electronic distributor and replaced it with a standard Lucas unit. I have also replaced the ignition coil. The engine runs exactly the same as it did , very roughly , with misfire? backfire every few seconds and the exhaust manifold has a dull red glow after around one minutes running....... Can't help thinking that it must be timing, and the problem is obvious, but what?
 
Glowing exhaust manifold is likely a sign of retarded ignition timing.

Have you tried advancing the ignition by ear? Simply rotate the dizzy until you get the fastest idle speed and then back it off a smidgen.
 
Instead of guessing, buy (beg/borrow/steal, delete as applicable) a timing light, then you'll know what the timing is set at now, you can set it to what it should be (6BTDC), and then if that gives problems with pinking than you can back it off until you lose that problem, and at that point you'll have a base setting that you can use in the future. You can also use it to check the mechanical advance.
 
Prior to starting the engine , I moved the ditsy by hand around 15 degrees in a clockwise direction ( I could move it no further as the vacuum mechanism was fouling number one plug lead) The car fired up immediately and ran at 2000 revs. I then adjusted the carbs to around 1200 revs at idle .The exhaust was still lightly puffing/ popping at the rear
The engine is still noisy but running more evenly and I should now be able to carry out a strobe timing check
 
My understanding with using the strobe, is that with the vac pipe disconnected I need to get the revs below 750. I can then connect the strobe to number one plug and use the 6 degree mark on the front pulley. I believe with the vac pipe then reconnected the light should veer from the 6btdc mark as the revs rise Is this correct?
 
georgecook said:
Prior to starting the engine , I moved the ditsy by hand around 15 degrees in a clockwise direction ( I could move it no further as the vacuum mechanism was fouling number one plug lead) The car fired up immediately and ran at 2000 revs. I then adjusted the carbs to around 1200 revs at idle .The exhaust was still lightly puffing/ popping at the rear
The engine is still noisy but running more evenly and I should now be able to carry out a strobe timing check
Click to expand...

That's great news! Some movement in the right direction :D
 
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