Nissan Repair: Blue Bird distributor, nissan blue bird, blowby

Question
Hi, I have a '94 Nissan Blue Bird - great car. But is has "blown" 3 distributors. I get about 10 - 12 months out of them- the sensor fails, i think it is either photo optic or inductive? i tried to convince the work shop that something was causing it, but they just continue to replace the unit at considerable cost, is there any history on this problem?

Answer
Tony,

If the rebuild unit is not as good as a factory unit that could be why they are failing about every year.  Also, if the optics are getting coated with oil it could just be that the engine has so much blowby that the seal goes and the distributor optics, shutter wheel and receiver are getting coated.