FJ 80 1990 landcruiser points burning out

Coil wired back to front.
Should be -(neg) terminal to points.
Hope it is that simple.
Regards Philip A

given it is a "points" system check it is the right coil.... meaning it either needs a "ballast" resistor to operate or not and see if it needs a ballast resistor......
The ballast resistor is used to give the coil FULL voltage only at starting and then power is switched to go through the ballast resistor to give it a lower voltage when running thereby making the points last longer....
Also check for a little "earth" lead inside the dizzy, if missing or broken it has trouble earthing and can cause weak sparks.
If it has been taken out or by-passed your points will not last long at all ....
Hope that helps
Joe

wizza,
Have you checked check the dizzy shaft for movement? if the bushes are worn it can cause the problems you are having.
Chris

The Best thing you could do is replace the points with an electronic ignition
put one in my son patrol, ideal for Lpg powered vehicles
The petronix system is very easy to fit and you will never have to worry about points again.
gives a good strong spark for lpg and will improve the engine tune.

Site Link
They list one for your model 80


Rob

Some great suggestions and all make sense.

I cut out a set of points every 10,000 kms, have experienced missing at idle and at revs.
Years ago points came with a small felt strip to lube the shaft. Current ones dont [in my case anyway]. Try a few drops of oil onto the dizzy shaft and see if that helps. Worked fo me.

Cheers.....Lionel.

Hi mate,
Sounds to me that your alternator may be overcharging causing excess voltage throughout the whole electrical system,
I suggest that you get an auto electrician to check the system with a good voltmeter. It should be generating 13.8 > 14.2 volts across the battery.
Any more than this will cause the problem you are having.
Hope this is of some help to you.
Regards, DS

I replaced plugs had faulty one bought new one was faulty bought another also faulty, check each plug for correct spark eventually engine ran great. remember new does not mean it will work, hope this helps.
Cheers.

Sorry Wizza, I cannot add more re your problem than has been already offered.

However, there is general mis-understanding about the function of a Ballast Resistor in a coil ignition system and I will try to explain:

The windings of an ignition coil have inherent "inductance", a characteristic of windings that slows the build-up and collapse of the magnetic field. This is undesirable as the speed of change of the field determines the ultimate energy of the coil output and hence spark.

To help overcome this inductance problem manufacturers made primary windings with less turns (hence less inductance) but then needed to use a ballast resistor to limit the maximum current to protect the coils and breaker points.

Observation of the voltage across the coil primary will indicate 9 or 10 volts, however the primary function of the resistor is to limit the current.

In some vehicles the circuit is arranged to bypass the ballast resistor during cranking in order to compensate for the reduced battery voltage due to cranking load and increase the spark power at that time. This increase in coil voltage, and hence current, is tolerable for the short duration of cranking. Furthermore, a rapid coil magnetic response is not as necessary at the low cranking speeds as it is at higher engine revs.

It is important that the ballast resistor is not removed or permanently bypassed in engines with coils designed for use with them. With the resistor eliminated an increased spark energy may be observed with manual operation of the points or during idle speeds but the ignition performance will be degraded at higher revs and also the increased coil current may damage both the coil and points with sustained operation.

The Ballast Resistor was very common in earlier ignition systems but has generally been eliminated due to "improved" coil design which reduced the inductance. Nevertheless it is still incorporated with benefit in some current models including electronic ignition systems and particularly in high performance, high revving racing engines.

Another technique to reduce the need for rapid magnetic coil response is to use more ignition coils per engine, often one per cylinder, so that the firing frequency of each coil is reduced thus allowing more time for the magnetic field to build up. This also has the advantage of eliminating the high-voltage distributor.

Hi Guys,
Thankyou to all that have replied to my thread,
what a great service this is !

I will print this and take in hand to my mechanic
the point made about the alternater is an area I don't think we have look at yet
But all taken on board I will post back on how we went.

I must add I did 80 kms over the weekend with Toyo genuine points and so far all seems good no miss thus far.

also have made a decision to go electronic and do away with the points all together ,but will be checking the alt for to much voltage first .
thanks to all that have thrown there hat in the ring
cheers
wizza