28 replies to this topic

[daryl_crossley]

yeah the 180 was for a few other bits too... it went for a tune while it was there and a new heater matrix installed....

not too sure on how to wire the leads to the back of the ignition though and if it will stop these problems im having but either way it needs a new coil so may aswell try it on a non ballast and see if it works

[mineeeeee]

You need to run a new cable from an ignition live from the fusebox,however is the fuse box
reliable?You could always run a cable from the ignition switch through a inline fuse
to your new coil thus making a dedicated ignition feed,eliminating the possably flaky
fusebox.

[daryl_crossley]

that sounds easy enough to do... if i run a ignition live from the back of the ignition then to an inline fuse ( what rating) and then link the yellow and white wire on from the solonoid that kicks 12v when starting this should work and obviously a non ballast coil and a new set of points and condensor and then fingers crossed im back on the road

[Retro_10s]

There may well already be a 12V feed on the fusebox already taped into the loom, look for a solid white wire,.. it'll re-appear from the loom down by the dizzy.

Quite a few of us have found this wire on Minis that had Ballast resisted set-ups as standard. So the swap is easy if you have the wire, I know, I did it.

You'll have to run a 12V coil.

Edited by Retro_10s, 07 November 2007 - 09:59 PM.

[Dan]

There may well already be a 12V feed on the fusebox already taped into the loom

Only present on 1984 and very early 1985 Minis.

Oh there's some new information, I thought you said you were using a Sports Coil, that's a Lucas brand name. The Lumenition brand ballasted coil is ONLY compatible with the genuine Lumenition ballast resistor. If you run it on the original pink/white ballast wire it will melt the points and also damage the coil so that it continues to melt points from then on. Sound familiar? This information is plain as day in the coil information and all the shops that sell it make it obvious too, if your mechanic fitted this coil to the original wiring for you he was negligent and you should get your money back. It must be fitted to a clean 12v feed through the Lumenition ballast. If you are using a 12v coil you don't need the yellow/white cranking bypass at all. If you fit the ballast resistor you do need it still. The cranking bypass is NOT a 12v feed, that's the whole point of ballasted ignition.

[dklawson]

"The Lumenition brand ballasted coil is ONLY compatible with the genuine Lumenition ballast resistor. If you run it on the original pink/white ballast wire it will melt the points and also damage the coil so that it continues to melt points from then on. Sound familiar? "

Now THAT is something to remember. Thanks Dan. I'll take mental note of that.

by the way, I sent you a PM through the board here.

[mineeeeee]

Well,well.well things start to add up now.
going on the above info if the resister cable is still ok
put your money into a good ballast coil and new points and maybe
condenser if its not new.
I know its not easy with all the trouble you have had as you seem to loose confidence in
the ballast setup but remember there are thousands of minis using ballast setups with the correct
parts(mine included) that have no bother at all.

[daryl_crossley]

sounds good even the mechanic agrees with this idea so its out tomorrow for a lucas ballast coil as it is a lucas ballast resistor that has been fitted to the car and new points and condensor and fingers crossed we have cracked it

[daryl_crossley]

ok so i have changed the coil, points and condensor and taken the car out for a run and managed a mile in the car before it started to chugg once again and the points were beginning to melt so i got straight back on the phone with the mechanic and he suggested changing the dizzy...... any ideas if this will cure the problem or is he just trying to string me along so i dont take it back to him

[dklawson]

bump again.

Describe what the points look like when you say they are burnt. Is it really the contact tips of the points that are burnt or is it the plastic wear heel on the moving arm of the points that's melting? When the car is chugging to its death, have you gotten out and felt the coil to see how hot it was getting? Do you have a multimeter or volt meter? If so, have you connected it to the car's electrical system so you can see what voltage the car is operating at while driving?

You've replaced a lot. In the last go round you replaced the condenser. How has this been connected inside the distributor? Where have you connected the wire from the condenser? Pictures would help.

[daryl_crossley]

ok where to start it is the wear heel of the points that is melting i believe.... have not felt the coil after the problem but it is a brand new one...multimetered when car running and 9 volts is going in and 6.3 volts coming out to the condensor earth wire.......condendor wire that is orange is connected to the moving arm at the top of the points... then condensor is screwed in and the black wire is run out of the condensor to an white with a black stripe wire which i think goes back to the coil..... i have been thinking about this connection and wondered if it possible to run the black condensor wire directly to the coil negative terminal.... also could it be possible that the wire at the back of the condensor that attaches in 2 places in the distributor could be broken even though it looks in good condition..... hope the pics help because it was dark when they were taken

Attached Files

•  PICT0025.JPG   966.37K   6 downloads
•  PICT0026.JPG   1.01MB   5 downloads
•  PICT0027.JPG   978.44K   3 downloads
•  PICT0028.JPG   984.32K   2 downloads

[dklawson]

That's a lot of information to discuss.

Let's start with the points melting. You said it's really the heel block that's melting. This is a more and more frequently reported problem due to some change in materials that has happened over the years. The best points are probably NLA, they are the ones with the "micarta" heel. Micarta is a brown phenolic plastic often reinforced with linen. When you look at it you can see the fibers in it. I assume that's a 45D4 distributor you've got. It may help to shop around at local parts stores... asking to SEE the points they have for that distributor before you commit to buy. You may find some new-old-stock ones that still have the micarta heel.

Second, make sure the square cam in the dizzy has a thin film of light grease on it. At one time there were special lubes just for the inside of the dizzy. I've found normal Vaseline to be suitable.

When you check the voltage on the coil... you really can't do it with the engine running. The current is flowing and stopping every time the points open and close. The way you need to measure this is as I described earlier. Remove the dizzy cap, stuff a coin between the points, turn on the ignition and probe between coil (+) and chassis ground. That will tell you the voltage that is reaching the coil while current is flowing through it. Switch off the ignition then mark and remove the low tension wires. Put your meter in "ohms" mode and probe across the coil's low tension terminals. Compare the resistance value you measure to those I posted earlier in this thread. You really cannot get accurate coil voltage measurements with the engine running and you can't get resistance measurements on the coil with all the other low tension wires attached.

Let's talk about ignition basics. Rather than repeat what I've written elsewhere, download this PDF and read up on ignition system basics.
http://home.mindspri...taticTiming.pdf
The condenser is wired in parallel to the points. In the attached picture of a 25D4 dizzy you'll notice that there are two wires covered with brown cloth insulation inside the dizzy. One goes from the dizzy housing to the breaker plate. This wire insures the points have a good ground. The second wire goes from the moving arm of the points to the lug where the black/white wire (that goes to coil (-) is attached). Now look at the condenser. The body of the condenser is its ground/earth connection. Some distributors may use condensers with two wires... but I'm not familiar with them. The orange wire shown in the 25D4 photo goes from the condenser to the moving arm of the points. If the condenser is not working because it has failed or because it is improperly connected, the spark at the points will typically cause them to burn out quickly and the car will run poorly.

At this point, I'd shop around for new-old-stock points with the micarta heel. Since the condenser is new, make sure it's connected properly. Also make sure the breaker plate has its dedicated ground wire in place.

EDIT: If the link below works, it is a picture of a set of points for the 25D4 dizzy. You can see the brown micarta heel clearly in the photo:
http://morrisminorsp...age.php?pID=130
also
http://www.datch.fr/...med/gcs2101.jpg
However, in searching for these pictures all I found for the 45D4 and 59 series distributors were the points with "blue" heels. Perhaps they never made micarta heeled points for the later dizzys? If not... have you considered an ignitor module?

Attached Files

•  25D4Picture01.jpg   231.58K   4 downloads

Edited by dklawson, 13 November 2007 - 12:33 AM.

[blahu]

I have very similar problem as the original poster, and I followed your howto...

If you have a volt/ohm multi-meter there are things you can check yourself to make sure the coil and its wiring are what you need.

Mark and disconnect the wires from the low tension terminals on the coil. Set the meter to measure ohms and place its leads across the two low tension terminals and record the resistance value. (Remove the meter from the coil and hold its leads together just to make sure that when they contact each other they say "0 ohms" or close to it. Let us know if the meter doesn't go to zero.) If the coil resistance you measured is CLOSE to 3 ohms, you have a non-ballast coil. If you measure between 1.2 and 2.0 ohms, you have a ballast coil and you need a ballast resistor (or resistor wire).

mulitmeter set to ohms - leads together 0.5 ohm
leads on LT terminal on coli - 1.8 ohm

I take it, its ballasted coil - it even says so on the coil.

Now that you know the coil type you need to measure the voltage on the coil. Place the low tension wires back on the coil terminals. Remove the dizzy cap and look at the points. Make sure they are closed. Place a coin between the points if they're open. Turn on the ignition switch and set your meter to measure volts. Place one meter lead on the coil (+) terminal (the one coming from the ignition switch). Place the other meter lead on a good earthing point... like a head stud. For a standard ignition you should measure battery voltage... somewhere between 12-13.5V. If you have a working ballast ignition system you will measure between 6-9V. Remove the coin from between the points if you had to use one.

it says 12.5V

I take it - the ballast is not working, or is missing.

Make sure you've got a ballast coil for use on the ballast ignition system and do not use a ballast ignition coil if you have +12V on coil (+) in the measurements above.

Go back and look at the wiring. You said you've got a ballast ignition system, so make sure the ballast connection to the starter solenoid is correct. On a ballast ignition system there should be a wire from the coil (+) to a fourth terminal on the starter solenoid. If a previous owner has connected this to the wrong terminal you may find this wire is always "hot" with 12V. That could cause the coil and points to overheat.

the wiring is quite a mess, so I will trace the cables later on.
Which one is 4th terminal on solenoid? how to count them?

Lastly, make sure you have a good condenser in there with the points. Replace it if at all in doubt. If the condenser is bad or doesn't have a good ground connection the points will wear out very quickly. Just to be clear... the body of the condenser has an earth connection through its mounting bracket. The wire coming off the condenser is connected to the moving arm of the points. If you earth the wire instead of putting it on the moving arm of the points it is not in the circuit at all.

EDIT: As a footnote to my previous post... the Bosch Blue is a standard 12V coil. I THINK (but am probably wrong) that the Bosch Red coil is for ballast ignitions.

Recenlty everything wa changed
- distributor
- dizzy cap
- HT leads
- coil
- sparks

the only thing that seems not changed is the ballast wire or ballast resistor.

I am planning to buy the ballasted coil + ballast resistor from minispares and install the electronic ingnition from lumenition (which I already have, but not installed yet)

Is that a good plan?

appreciate feedback

-mat

[Ethel]

You shouldn't need ballasted with electronic ignition, but the important thing is use a coil that is compatible with whatever your system requires. you can measure the resistance between the coil's +ve terminal and ignition switch to see if the ballast resistance is right - around 1.5 ohms.

If you do use ballasted, there should be a second spade terminal on the solenoid (not connected to the battery or motor screw terminals) that supplies 12v to the coil when the engine is being cranked.

I'd just follow the fitting instructions for the leccy ignition.