Bits and Pieces

Electronic conversion to T-Type distributor

Just a brief note regarding the fitting of an electronic conversion to a T-type distributor.

I know of 3 people (including myself) who have had failures with these units.

The problem is that the clearance between the rotor arm and the distributor cap is very small.
Fitting an actuator ring underneath the rotor arm  will raise the rotor slightly so there is a risk that it will rub against the bottom of the distributor cap.
This rubbing causes the rotor arm to get very hot, very quickly.

If you are using a modern plastic rotor arm, it will simply melt.

If you still have an original Lucas rotor arm it will not melt, but it will transmit the heat to the electronic module, which will overheat and then fail.  (It may recover when it cools down).

So, if you have fitted an electronic conversion to your distributor, I recommend you unclip the distributor cap and inspect the top of the rotor arm for any signs of rubbing. If it is rubbing, the solution to the problem is quite simple. 

Pull the carbon brush out of the distributor cap, machine a small amount off the central guide tube with a Dremel tool, and then replace the carbon brush. Barrie Jones

TC gearbox end covers

Further to the item in the June TTT 2, Paul Busby has received strong interest and has made a batch. Price for backplate is £350.00 with or without oil seal recess (oil seal and supersleeve not included) plus £5 for postage UK or £20 for USA and Canada. Only one left (with oil seal recess) luckily the foundry cast a couple of extras. pyb.7(at)tiscali.co.uk [please substitute @ for (at)].


One thought on “Bits and Pieces

  1. Bernard Grumer says:

    I bought a Pertronix electronic conversion LU-146LSP12 for my MG TC distributor DKY4A 40162E. This conversion does not include a black ring as other conversions include. the signal for the spark is initiated by the shaft lobes when they pass by the sensor hins the distance between the lobes and the sensor very small. There is an interference between the rotor arm and the sensor. is this problem known by others using the Pertronix on their TC’s

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