22 replies to this topic

[se_juggles]

Had someone to come and view my mini today because im selling it. they really want it which was good but like all minis she decided to be a ******* at the wrong time and has no spark now!

I have no electrical testing equipment so i cant tell when something has a live or not. Sadly its all about 90 miles from me and my works handy man only has mains testers which dont seem to work at all.

it has a pre engaged starter motor and a electronic ignition coil and distributor. at first it wouldn't turn over atall so i replaced the relay and then it turned slightly but the battery was dead. i linked the battery and to my mates car and nothing so i checked the spark and there is no spark atal coming from the coil.

i made sure the engine earth and the battery earth where ok and they seemed to be fine so i ran a cable straight from the fuse box (the same one as the indicator) and still no spark.

to me it seams like an earthing problem because not even running power straight to it gave it a spark

at the moment the starter is the wrong one. its ment to be the inertia but i had the engine switched over to an a series and to loom is to short to connect the inertia type. it did start fine before though, i removed the starter and it all seems to be in tacked so accept the noise at the moment it isnt doing any harm (i've told the guy he needs to get it switched over.)

if anyone can list stuff to trouble shoot ill be very grateful.

cheers se

[KernowCooper]

You need to get the battery charged and when its at 12.65v its full charged, check the battery terminals are clean and secure, then undo the 5/16 half inch AF spanner size earth strap from the body and make sure its clean and corrosion free.

If thats ok we need to move on the then to the engine end, here is where your going to struggle without a volt meter and I cant see how you'll be able to trouble shoot the fault. I'll run through what your looking for though. The end of the main battery cable from the boot should be tested for voltage and should be the same as the battery voltage in the boot, so assuming the battery is fully charged with the volt meter on end of the battery cable and a cylinder head stud you should see 12.65V, if you get no reading then check the earth strap between engine and body, clean and replace as necessary.

Ok assuming we now have the correct voltages as above were going to check out the voltage to the coil you have a + connection on the coil so connect the volt meter on this and your newly cleaned earth or head stud switch the ignition on and depending on if its ballasted you should see 9v or a non ballasted coil its 12v note those readings, if they are correct then we have voltage to the coil. If its a points and condenser distributor then I'd replace those as they are cheap enough and check the connection from the - connection on the coil to the wire to the distributor. If all those are correct then we should have the coil able to produce a spark. Ok just reread you post and you have electronic ignition so test the coil as below.

Ok lets check the HT Leads, rotar arm and distributor cap, the HT leads including the coil king lead from the coil to the centre of the distributor cap should all have a tight connection and no green corrosion, when we get the car to crank over later we can do a basic test on the king lead by holding the end which fits into the distributor cap about 1/4inch from the metal coil bracket and when cranked it should spark, you may wish to hold this lead with insulated pliers to avoid a shock. if it sparks we can move on the check the cap and rotor arm. the cap should be free from cracks inside and the carbon brush should protrude from the centre on its spring, the rotor should also be free from hairline cracks.

Ok lets move on the the starter issue, The incorrect starter is not correct as the ring gear on the flywheel is different for a inertia starter than a pre-engaged and the wiring is totally different. The inertia starter has a solenoid on the drivers inner wing which the battery cable from the boot connects to one side the other side of the large terminals goes to the starter, the solenoid has a 12v trigger wire from the ignition switch in the cranking position to make the connection. The pre-engaged one has the large battery cable from the boot connecting to the upper terminal of the inbuilt solenoid on the starter and the other side of this goes to the starter and is always pre-installed on the starter motor, there is a 12v trigger wire exactly the same from the ignition switch on a small terminal. Depending on the model of the car the connection from the boot to the upper terminal of the solenoid may also have additional wire to provide 12v to other components on the car.

Thats your basics but to solve your problem there are basic tools your going to need to solve problems on a car and in this case one of those is going to be a volt meter, you may strike lucky and find one of the many connections broken or corrosion on it and that could well be your problem.

I don't wish to be rude but the wiring on the starter could be a codge (good ole cornish word) and the noise its made when it did crank is trying to tell you something.

Volt meter or get someone who has one is your way forward I think.

Edited by KernowCooper, 02 March 2013 - 12:33 PM.

[se_juggles]

so it could be something as simple as the battery not being charged properly Or something more serious like the coil being *******? Will the starter motor have any effect on this because its the wrong one? And also there are 2 connections in the relay plug that have green corrosion. Would this be the problem by any chance or would that prevent all ignition?

Thanks for the reply se

[KernowCooper]

What relay plug are we talking about thats got green corrosion ?

Its not a cut and dried as the coil being faulty you have to do the checks to find out what is faulty and thats a check of the electrical system. It sounds from your description of thing you could have several faults, and sorry there is no easy way without some basic knowledge of electrics and a volt meter and do a series of basic checks I'm afraid.
I can't see the the starter motor causing the coil to fail if indeed it is the coil, Its a process of elimination and working your way through the electrics as above.

Now you have the list of where to start you need to confirm all the steps are correct and work through it until a fault is found, if your not ok on electrics its best to call in someone who can help you with the correct test equipment, otherwise its like giving information to a member who's asking how to fit a new clutch but he has no spanners. Beyond visual checks your going to struggle to find the fault.

You mentioned you changed a relay ? which one?

I re-read your post how old is the mini and what model are we talking about, also put your location in your profile as there may be a member here who can come round with a meter.

Hope that helps

Edited by KernowCooper, 02 March 2013 - 03:32 PM.

[dklawson]

Additionally, how have you been checking for spark?

[se_juggles]

I've been checking for a spark the same way I have previously. I remove the king lead from the dizzy and leave it connected to the coil and then I put a screw driver in the lead and hold it close to bare metal (not practical but I'm a chef and knives cost me enough without working .out cash for even more tools lol)

I'll be getting a volt meter this Monday hopefully and the part that has corrosion on it is the bit the relay connects to on the left hand side of the engine bay, near the bulk head. From what I can see from the wires it is the wires that come from the starter motor solinoid (hence thinking this could be a cause).

The mini is a 1989 998cc and previously had a a+ in it but was switched to a reconditioned a series 998cc when the mot gave me a warning on the amount of oil leaks the engine had.

[se_juggles]

ok so today i got back out there armed with a volt meter and the readings where as followed.

12v from the battery, 12v to the starter, 12v from all the fuses accept the bottom one which i couldn't get any reading at all from, 12v to the relay but nothing from any other part (ignition on or not), 12v to the + coil on both parts, 12v from the - coil on both parts, 12v to the dizzy on both parts, 12v to the alternator,

engine seems to be earthed fine.

im ripping my hair out here!!!

anyone help.

[se_juggles]

got a new ignition module coming tomorrow. apparently the resisted wire i was using before was incorrect and i need to wire the electronic ignition with a different wire :S.

I was not aware of this so silly me!

[Wakey-Dan]

Keep us posted juggles, Im currently having the same problem. Cars at my dads and Im going over tonight with a voltmeter to test the coil and the wiring to the coil.

[dklawson]

I did not realize that your electronic ignition was a conversion from standard. Supplying the ignition module with a full 12V supply (not via the resistive wire) should make a big difference.

Keep us up to date and let us know if changing the power connections for the ignition module addresses the problem.

[se_juggles]

ok i wired in the new module and she started straight up without the choke. but was on 3 cylinders as i have a plug off to check the spark lol.

turned her off and connected the plug. once again she started straight up. but as there is no oil in the dash pot and the carb has just been refitted with a different needle the revs went to high but wasn't sure how as the rev cable was what im guessing is the black and white wire that connects to the coil? i turned off the engine. just tried again to make sure and once again a good start. i then attached the/ what i think is the rev cable and the module is kapput again

anyone that can help please do as these modules are £24 ea! and this is becoming an expensive sale to say the least!

cheers se

p.s how do i connect up the old a series dizzy and can it be run with a powersparks sports coil if it isn't electronic???

Edited by se_juggles, 07 March 2013 - 05:18 PM.

[dklawson]

Where did you attach the white/black wire to the coil? If you take the white/black wire OFF the coil, will the engine start again?

Your second question is about fitting a different distributor (presumably with points) and connecting to a sports coil. Without the electronic ignition your sports coil will offer no advantage but it will work fine. You fit the distributor where the electronic ignition dizzy is now. There will be a short wire (typically white/black) that goes from the points in the distributor to coil (-). Once you fit the points distributor and connect its single wire to coil (-) you must set the static timing. If you are not familiar with what is involved with static timing you can download and refer to my PDF on the subject.
http://home.mindspri...taticTiming.pdf

Before static timing the points distributor you should clean and properly gap the points.

Footnote: In a recent thread a poster mentioned that they fitted a new distributor and earthed all the unused old wires. In their case that included earthing the un-used white/black wires. (I hope that wasn't your post.) There can be (2) white/black wires depending on what is in/on the car. For cars built with a points distributor there will be a SHORT white/black wire in the loom and that wires goes from the coil (-) terminal to the dizzy. If the car included a Smiths RVC tachometer it will have a second white/black wire that goes from coil (-) to the tachometer. When you are fitting your points dizzy, make sure you know have both ends of the same, short, white/black wire when you connect the distributor to the coil (-) terminal.

[se_juggles]

nope the white and black wire just killed the module again. i get no spark again so thats another module gone and more money forked out for a new one. i connected it to the - i think on the coil but i checked it with a multimeter and there was no power so i don't think i shorted it out.

so basically i simply just wire it so the original white wire connects to the + and then the black wire from the dizzy connects to the - and that is it???

[dklawson]

White and black? I think it is time for pictures. Please post what you can.

Some/most points ignition systems ran a white wire from the ignition switch to coil (+). That is a switched, un-fused 12.5V power supply to the coil. A second wire (white/black) ran from coil(-) to the dizzy. The white/black is a wire providing a connection to the points and therefore... earth.

You said: " connected it to the - i think on the coil but i checked it with a multimeter and there was no power so i don't think i shorted it out. "
No power where?

Let's step back for a moment and discuss the basics of how this system works. I am going to use the words "points". However, the electronic ignition module is basically an electronic set of points so the operation is the same. I am not going to mention the condenser used with points in what follows.
Consider the coil to be a transformer.
When the points are closed and ignition is on, a magnetic field builds up inside the coil due to its many "primary" (low-tension) windings.
When the points OPEN the current flow stops and the magnetic field collapses.
When the magnetic field collapses this creates a huge voltage spike in the "secondary" (high-tension) windings of the coil.
The high-voltage is delivered via the main spark plug lead to the distributor cap where together the cap and rotor direct the voltage pulse to a spark plug.

In the case of an electronic ignition module you have what amounts to a solid-state relay (switch) triggered by a magnet, a beam of light, or similar. When the shaft inside the distributor rotates it causes the module to turn "on" and "off" simulating what the points do when they open and close. For this electronic switch to work you supply it (typically via a red wire) with full, switched +12.5V. The mounting surface of the module is typically bare metal and this establishes an earth connection for both the coil current AND the electronics of the module. The electronic module has (typically) a black wire that connects to coil (-). When the module is conducting ("on"... equivalent to points closed) current flows from coil (-), down the black wire, to earth through the module. When the module is not-conducting ("off"... equivalent to points open) the current flow through the black wire and coil is interrupted and the high-voltage pulse is created.

So, what you are looking for (with the ignition switch ON) is...

• Battery voltage (nominally 12.5V) on both coil(+) and the module's power wire (usually red but I have seen white for some OEM products).
• With the module's black wire connected to coil (-) you will measure either 12.5V or 0V on coil (-) depending on whether the module is "on" or "off".
• If you connect the meter between coil (-) and earth and have a friend crank the engine on the starter you should see the voltage swing between 0V and 12.5V as the module turns on and off respectively.
• Note that the voltage is not necessarily 0V or 12.5V on coil (-)... it changes depending on whether the module is on or off.

[se_juggles]

ok well i get a reading of 12v constantly on the (-)side of the coil,

what i meant was i checked if there was any power coming from the white and black wire before connecting to make sure i don't run power straight into the (-) side of the coil.

honestly im really tempted to just get a old non electronic coil so i can just sell it. i did connect the old dizzy to this coil though and it had no spark again. the dizzy did work before but that was a while ago so it may have gone. i conected the black wire from the dizzy straight to the (-) and then the resistive wire to the (+) and the black and white wire to the (-) aswell that is all that was connected but still again it read 12v everywhere but no spark!


i quit. im gunna go push it down a hill!!!!!