12 replies to this topic

[Nealmc14mini]

hi this is my first post with my first mini im 14 and pictures are on my facebook NealMcEnroe any way my problem is that i have no spark at the points or plugs i have power to the coil i need to now how i can do a proper test on my distributor as im there is power in the distributor can i do a test on the condenser? it is well earthed with a fresh battery i honestly dont know where to start? everything else is fine apart from spark??

[dklawson]

Welcome to the board and where in VA are you?

Before starting to respond to your questions, let me first ask that you use punctuation and capitalization (regardless of whether you are using a phone or PC to post). These items are part of the board rules.

To troubleshoot an ignition system you need to understand the basics of how they work. I suggest you download the PDF in the link below and get a general understanding of what is supposed to happen and why.
http://home.mindspri...tsIgnitions.pdf

Suffice it to say that the high-voltage pulses necessary to create a spark only happen when the points in the distributor open. Therefore the points have to be properly adjusted and you will not see sparks either at the points or at the plugs unless the engine is turning over causing the distributor shaft to rotate.

Testing a condenser is generally handled by replacement. That said, how old is your Mini? Early Minis used the 25D Lucas distributor. There are some plastic spacers/washers used with those points that MUST be in their proper positions or the ignition system will not work properly. If the washers are in the wrong place it is as if the points never open.

[Nealmc14mini]

Hi the Mini is an 1983 998cc Mayfair which has got a complete resteration and rebuild the engine was not rebuilt as it only has Thirty four thousand miles and has a new coil i dont really now much about it as i was told that it was running. I can see that the points are opening and closing with no spark and I also tried moving them with a screwdriver but still no luck is their any tests I could perform on the condenser ?
Thanks for your reply

[Nealmc14mini]

VA? I live in Virginia Co.Cavan in Ireland?

[dklawson]

VA? I live in Virginia Co.Cavan in Ireland?

Oh... Sorry. The text below your avatar says "Location: Virginia". Being from the U.S. I automatically assumed that you were from the Commonwealth of Virginia, just north of the state where I live.

I will repeat my earlier suggestion that you download and read over the PDF I provided a link to in my first post. The document explains the basics of how the ignition system is supposed to work and includes a troubleshooting section to help you find out what is going wrong. The more you understand how the system is supposed to work (and it is not too complicated), the easier it will be for you to find the problem.

Also from my first post, condensers are usually tested by replacing them. The condenser is a capacitor. While a few multimeters have settings that allow you to test capacitors, most inexpensive ones do not. Therefore, it is easier to replace the condenser rather than try and test or measure it. They are not expensive.

[rosswalki]

Hi, had the same problem with mine a month or so ago. Turned out to be the earth wire inside the distributor but I also fitted an electronic ignition and runs a lot better now. Also check the HT lead from the coil to the dizzy cap and that it's in time. I'm on my first Mini at 16, they're great little cars, always wanted one. Ross

[Nealmc14mini]

Hi found out that my coil is gone its a brand new lucas so orderd another and will repost in a fewdays wen i get it. Thanks very much for your replies and the pdf!
Thanks

[dklawson]

How did you determine that the coil was bad?

Do keep us updated on your progress!

[Nealmc14mini]

Hi when testing the coil i was only getting 0.3 ohms and when turning the engine over it was the same i also got a local mechanic to look at it and he said it was kn**kered! so hopefully a new one will work... Is there any other 14 year old's that has done a rebuild on a mini on this site can. Where can i post the rebuild process.? Thanks

[cooperrodeo]

If the coil is only 0.3 Ohm, what else has failed as a result of this?

[dklawson]

To post your rebuild work, visit the section of this board linked below (Mini Engine Projects):
http://www.theminifo...hp?showforum=60

Concerning checking the coil, you must have all the low tension wires disconnected when you measure coil resistance. If the low tension wires are connected your measurements will be influenced by other components. You also said: "and when turning the engine over it was the same" You cannot check resistance with current flowing through a circuit. Disconnect the coil low tension wires and repeat your measurements.

Coils seldom go bad. Yes... they do fail. However, the way they fail is typically for them to cause high-speed misfires and/or completely stop working when they are hot.

Take a look at the PDF again. Below is one of the tests I suggest you try to evaluate your coil.
1) Remove the plug wire for cylinder #1 from the distributor cap. Remove it complete with its spark plug so you have a plug wire with the plug still attached.
2) Remove the plug wire from the big center terminal on the coil and replace it with the wire you removed in step 1.
3) You should now have a plug wire and spark plug connected directly to the coil without using the distributor cap. Rest the spark plug body on a bare metal spot on the cylinder head.
4) Remove all the wires from the coil (-) terminal. LEAVE the low tension wires on coil (+).
5) Connect a jumper wire about 200mm long to the coil (-) terminal.
6) Turn the ignition key to the run position so there is power supplied to the coil (+) terminal.
7) TAP (do not hold... TAP) the other end of the jumper wire to a bare metal spot on the engine block.
8) Each time you lift the wire off the engine block, watch the spark plug.
If the coil is getting power (measure it to confirm 12V is on coil (+)) and if the coil is in working condition, you will get a spark at the plug each time you lift the wire off the block.

Again, coils seldom go bad and you cannot measure their resistance with current flowing through the circuit.

EDIT: Don't give up the faith. It's great that at 14 you are taking on this challenge. However, take your time and try to understand what each task you are undertaking is trying to achieve. Read a lot in advance regarding your planned engine rebuild. There is a lot to be learned here and from other boards. You are fortunate that the Internet is at your fingertips. When I was 15 and working on MGB engines and ignition systems all I had was the manual and I made many mistakes along the way.

[Nealmc14mini]

Finally got it running with a new coil..... Thanks

[dklawson]

It is great that you got the engine running. You said you put a new coil in. What else (if anything) did you replace or do?