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[Reg]

Just fitted new battery,no change. No spark at points which are opening and closing ok, and gapped 15thou.
Voltage at points is 0.02 with points open.I would have expected 12v.but I'm no sparky. I've looked at everything I can get at and sprayed liberally with WD40. Ammeter shows a healthy discharge now when ignition is switched on, which it didn't with the old battery. Reckon I'll try another new condenser, (threw the old one away) before changing the coil. I don't think it's a carb problem as it won't start at all now. Any ideas would be much appreciated.

[jaffa90]

Reg,what`s the battery voltage before switching on and again when switched on and again when turning engine over?

[Paulk]

Reg, I would expect 12V (or thereabouts) at the points if all was good (with points open). As a quick hot wire to check components you can take a wire from feed side of battery to coil, other side of coil to points. This leaves only the battery, coil and points/condensor in the game. If it doesn't spark now you know it's one of these bits, if it does spark/run you know to look at the wiring and other stuff. As for 10V mabye good enough take a look at the table in para 6 of http://www.batterystuff.com/kb/articles ... asics.html Good look, Paul.

[Alan R]

Hi REG ---- This odd reading of 0.02 volts at the points ??---how are you connecting the meter ??--Turn the engine until the points are open--- Now, with the ignition turned ON (have you got an emergency cut-out switch ?? Make sure that is ON) and VOLTS selected on your test meter(as near to 0--12 on your scale that you can get) attach one lead to the feed wire that is coming into the points from the loom, and the other to the body of the distributor....You should now be getting a full deflection on your test meter..... If not then there is a problem along that feed wire and back into the H/T coil, etc..... If you are getting a reading then there is a problem within the points/capacitor assembly.... You need to look for a spark at an earthed plug.... If you have been getting a noticeable spark at the points then this is normally an indication of a failing capacitor.... If you have recently changed the points or capacitor then double-check that the two flat washer-like connectors---one on the points, one on the capacitor----are FULLY INSULATED on the fibre mounting.... If either of these shorts out to earth then you will NOT get a spark at the plug...... Just to help with understanding the set-up, when the points are OPEN then the battery is connected directly to the capacitor via the H/T coil ( At this point the capacitor is actually helping to boost the intensity of the spark---hence it's more common name of "condenser".)... When the points close, they short-out the capacitor and the battery is now connected only to the H/T coil which is reaching saturation point (ie, magnetic field saturation)....Have a look at this}---- http://mgaguru.com/mgtech/ignition/ig104.htm ---------- The schematic wiring is exactly how your Bullet is wired............ Phew, this "Distance Diagnostics" aint easy!!!

[Alan R]

Hi JAFFA & PAUL, --- Sorry lads, your posts came up whilst I was typing. Bit of duplication I'm afraid.

[Mark M]

Reg, you've now changed so many things that confusion is inevitable. If you can, go back to the component set up you had at the beginning, (except the original battery which does seem to be faulty,) and start again. Never change two things at once when trying to trace a problem, it just introduces more uncertainty, even if it does fix the problem how will you know which component change fixed it?
REgards, Mark

[Norm]

Reg, firt get a test light, ignition on and points open you should have power at both sides of the coil, then check the points, spring on the points should have power. If not check the kill switch or the insulators on the points have been fitted incorectly or you have a broken wire somewhere. Come back and tell us what you find so we can continue to help you fault find. A lot of this is one step at a time

[Paulk]

Alan, No problems, nature of the beast we're all only trying to help. Reg, As an add on to what I said before if you temp wire the bike as I said before but don't connect the final wire to the points but instead "flash" it to a ground point (like your engine cases or your cylinder head) if you get a spark at the ht then you know your coil is good, if not it's duff. Similary if you do this first and get a spark then attached it to your points and don't you know your issuse is with your points. As Norm pointed out stuff like this has to be handled methodically and not a buch of random guesses - unless you thave nothing better to do and like spending money on stuff you don't need. Good luck, Paul.

[Reg]

Fired the bike up the other day, more in hope than anything else. Despite dramatic back-firing decided to ride it up the lane. No change, after a mile got back to workshop switched off ign. and guess what? massive pre-ignition. Engine revving really fast and would only stop after turning off petrol.(I realize now that putting the choke on might have had a more immediate result). I haven't interfered with the timing. Have since checked it and all seems in order. Think I'll re-fit the points and go through everything with minute attention to detail. It has to be something really dumb.

[jaffa90]

No voltage at points,running over for ages,i would check that ignition switch.Previous advice ignored.