Thread: Contact breaker issues

I think from memory there are some nylon rubbing blocks between the top & bottom base plates so the plates can slide on each other , you may find one is broken or worn causing the top plate to tilt.

A good time to buy an electronic ignition module to replace the points.

Originally Posted by Red90

A good time to buy an electronic ignition module to replace the points.

Originally Posted by DieselDan

G'day All,

I have an ongoing ignition gremlin issue with my S3 Lightweight but thought I'd post here as it's more a generic Lucas Prince of darkness issue!

The engine suffers from misfires, rough running and the occasional 'failure to proceed' that I have traced to an overheating coil. Let the coil cool down and all is ok again for a while.
The coil is a 3ohm (I've checked) NGK job that's pretty much brand new.

While looking through the rest of the ignition system, I've come across this odd problem with the contact breaker.
I was trying to set the gap, but couldn't seem to get any gap at all and then I noticed that the base plate that the points sit on is tilted at an angle. The contact breaker is only touching the cam at the very bottom and not enough to open the gap.
If I push down on the opposite side, the base plate levels and lo and behold the gap opens up.
I'm amazed the thing runs at all because I took the contact breaker points off and the profile has been worn at an angle. So the base plate is still in a tilted position when the dizzy cap is on, but seemingly the points gap manages to open enough to create the spark.

So I'm thinking that the points being closed for too long/barely opening is contributing to my overheating coil but has anyone seen this issue with the tilting base plate and any suggestions of how to solve it?
Cheers.

Originally Posted by 1950landy

I think from memory there are some nylon rubbing blocks between the top & bottom base plates so the plates can slide on each other , you may find one is broken or worn causing the top plate to tilt.

I have also seen the flanged pin that locks the sliding plate to the base plate wear. If you pull the base plate out & look at the underside you will find the pin has worn a grove along the slotted hole it moves in , this will cause the sliding plate to rock on the base plate InkedDistributor_1_LI.jpgPin is under sliding plate 1 , slot for pin in base plate 2. The sliding plate can be taken of the base plate by removing the assemble from the distributor then rotate the sliding plate so the pin lines up with the round hole in the slot then the two halves will come apart . You will need to check the slot for wear & also the pin. these wear because they never get lubricated except when new , the sliding plate moves when the vacuum advance operated .

Originally Posted by Red90

A good time to buy an electronic ignition module to replace the points.

Originally Posted by DieselDan

G'day All,

I have an ongoing ignition gremlin issue with my S3 Lightweight but thought I'd post here as it's more a generic Lucas Prince of darkness issue!

The engine suffers from misfires, rough running and the occasional 'failure to proceed' that I have traced to an overheating coil. Let the coil cool down and all is ok again for a while.
The coil is a 3ohm (I've checked) NGK job that's pretty much brand new.

While looking through the rest of the ignition system, I've come across this odd problem with the contact breaker.
I was trying to set the gap, but couldn't seem to get any gap at all and then I noticed that the base plate that the points sit on is tilted at an angle. The contact breaker is only touching the cam at the very bottom and not enough to open the gap.
If I push down on the opposite side, the base plate levels and lo and behold the gap opens up.
I'm amazed the thing runs at all because I took the contact breaker points off and the profile has been worn at an angle. So the base plate is still in a tilted position when the dizzy cap is on, but seemingly the points gap manages to open enough to create the spark.

So I'm thinking that the points being closed for too long/barely opening is contributing to my overheating coil but has anyone seen this issue with the tilting base plate and any suggestions of how to solve it?
Cheers.

Originally Posted by 1950landy

I think from memory there are some nylon rubbing blocks between the top & bottom base plates so the plates can slide on each other , you may find one is broken or worn causing the top plate to tilt.

The other thing to look at is the flanged pin that locks the sliding plate to the base plate. The pin can wear a grove on each side of the slot the pin moves in as the sliding plate rotates when the vacuum advance pulls it. If can cause the sliding plate to rock.

Thanks guys.
Ha, yes I spent some of last night googling electronic ignition modules!!
I'll pull the base plate out and see what I can find, thanks for the tips!

I have not seen one tilting like that, but my immediate thought would be wear in the distributor - the contact breaker is rotated by the vacuum advance, and wear on the bearing surfaces would cause this.

The other thing that I would check is that the coil is actually intended for 12v, not one designed to use a resistor, although the resistance of 3ohms sounds about right.

Unfortunately Lucas distributors were poor when new and age hasnt helped them. You can buy point type replacement distributors cheap from England and locally. I found a seller on Ebay with electronic distributor complete at a very good price. There is no load on the breaker plate and the engine starts easily and runs great.

For reliability i would fit one of these and if crossing the simpson desert i would take a spare point type dissy that works.

Make sure your coil is the correct type to the voltage you are connecting it to. Similar thing old coils wear out and need replacing every 10 years or so.

Lucas Ignition parts are cheap from England and if you need any other bits. Lucas parts used to be very cheap in Australia a long time ago but they seem to have gone up a lot for no reason.

I hope this helps

Ian
Bittern

Thanks JD and Ian.
The coil is correct (non resistor type with 3ohm impedance), but I've got a spare if needed.
I'll check out the entire replacement distributors that come with the electronic module, they sound good.