75% running but why not 100%

[bluecrayford]

Just a thought, though I dont know why it should affect it the way it is, is the oil pump drive ok where the dizzy slots in ?
How did the fault originally start, did it just drop off a cylinder or where you doing something else when it started doin it?
You have one bizarre fault there matey. Electronic ignition might help by eliminating all the moving parts, but what if it still does it?

[pbottomley]

Yea I had been thinking of the oil pump slot not being right. If it is slightly offset form normal then it might be torquing the dizzy shaft to one side at one part of its rotation and pulling the rotor arm away from the cap and stopping it sparking the HT lead???

However I have turned the car over with the cap off and all appears to turn as one would expect??? I will try to find some time on Sunday to pull the dizzy again and turn it over and watch the oil pump turn, alas is hard to turn the car over on the key and look down the dizzy hole on me own! If this takes a week or two to diagnose and fix so be it.

[shamm]

Put a lamp across the points and wind the engine over by hand, might tell you something.

[pbottomley]

Right long story short (if possible)

pulled dizzy checked oil pump is rotating square to the dizzy CHECKED okay

pulled dizzy to bits and rebuilt it, checked every wire with voltmeter and then every possible part I could get the voltmeter onto for earth issues (all fine)CHECKED okay

Checked cap with voltmeter CHECKED okay

checked LT lead with voltmeter CHECKED okay

set up points again to 31 thou CHECKED okay

checked plugs CHECKED okay

checked HT leads CHECKED okay

checked Rotor arm CHECKED okay

put dizzy back in car , fired it up runs on all 4

Only issue is now cannot run car for long as battery not charging car enough for me to risk a road trip and see if vibration makes it go back to running on three again.

Will sort alternator this weekend then report back findings