Nissan Repair: stalls out after 20 min, vapor lock, urvan

Question
hi, i have an old 1982 urvan, i purchased it about a year ago.  half way from melbourne to Qld it started stalling out at 100 kms/hr. i slowed down to 80 and it went for a bit, this continued down the gears until i limped it in to a town in first bunnyhopping. after being told i scraped down the points on the dizzy cap. this got it another 800ks. for the next 6 months when the problem happened i did the same, it would go again but for less distance each time, until no scraping down would help. since then ive had it looked at, changed coil, points, condenser. it will drive well for 20 kms then die, but still idle fine. mechanic cant find a problem. please help

Answer
Jacob,

I would check to see if the coil is overheating.  When the vehicle dies you need to have a test light on hand to see what is going on.  You will need to see if the coil has output when the vehicle dies.  I would think the vehicle starts up after it cools down?  Email me back and let me know.  Now, if the coil checks out good then we need to look for a vapor lock.  I am in Las Vegas and it is cold here but you are having a nice bit of Summer where you are?  Anyway, let me know what you find.