Originally Posted by Jgwright

No the part is not an optical sensor. It is a kind of inductive sensor. I wish you luck in extracting it as the 2 engines I have worked on had them in very tight. The part you are looking for is the one at the end of the blue lead. The ones I had did not have any part numbers on them. If you cannot get hold of Arno you could try Turbine Rescue and see if they know the part no.

The only alternative is to change over to the Xicoy unit, but the internal Kero plug is 12v and it will not work as the Xicoy unit only runs to 10v and you will have to devise alternative ignition. I would warn you that working on these engines is not for the fainthearted. Take plenty of photos so you can get it all back together correctly.

John