[Adrian II]

... fully retarded.

A.

[French MK]

Well took it for a test drive up the road. Felt promising when going up the drive in first.
On the road,  back to how it was missing/spluttering, just not picking up at all. ticks over and starts fine...

Stator? its the only bloody thing left lol.

[French MK]

Well took it for a test drive up the road. Felt promising when going up the drive in first.
On the road,  back to how it was missing/spluttering, just not picking up at all. ticks over and starts fine...

Stator? its the only bloody thing left lol.

Would dirt etc effect the stator to make it run like it. Although looks pretty good....

[AzCal Retred]

The coil only cares about battery voltage and contact point opening. With a hot battery you could toss the stator & rotor and run fine until the battery voltage finally dropped too low.

Contact points open when the point cam hits the micarta point arm. This makes the coils magnetic field collapse and induces a high voltage spark on the high tension side to the plug. IF the point cam isn't steady, held securely & rotating smoothly on its bearings/bushes, the points can "bounce", the flopping point cam opening & closing them irregularly initially instead of a clean break at the right time. This affects spark quality, making & breaking irregularly and not allowing proper field build up and collapse. Too small a point gap can mimic this by allowing arcing as the points separate. Way too large a gap can also cause bounce at higher speeds as the points arm falls off the cam and just mechanically bounces open again after the point surfaces connect.

The mechanical advance unit provides about 32 degrees of ignition advance, most of which happens around 2000 RPM. It has to operate smoothly. Finger pressure will allow you to rotate the cam & see the flyweights move. The springs attached to the flyweights needs to be firm, not loose. These springs weaken over time and are replaceable. The spring strength determines when the advance happens. Stronger springs delay advance.

Timing on the stock motor is problematic. The normal practice is to set the base timing at 0.8mm BTDC, having removed gear lash by rotating the wheel in the forward direction in 4th gear. This gives you an "idle" advance of I believe around 4-6 degrees. The "washer method" times the engine at full advance, having locked in the point cam and shooting for 8.0mm BTDC.

If you want actual timing and advance numbers you'll need to pull off the primary cover, fit a degree wheel & pointer, set up your timing light, THEN you can see the actual advance.

Your job is to eliminate the variables until it has to run. Water in the float bowl, a crack in the rubber intake manifold, excess radial play in the distributor shaft or advance assembly, marginal ignition coil or condenser, loose wiring, hinky switches, bad fuel, funky spark plug, any and all of these can create issues.

[stinkwheel]

Would dirt etc effect the stator to make it run like it. Although looks pretty good....

Almost certainly not. Yes it looks pretty good.

Remember you need to centralise it round the rotor when you put it back on so it has an even air-gap all round. I find a slice of aluminium beer can is the perfect width to use as a shim between each winding stack and the rotor. Bolt it down to finger-tight with shims in, make sure they are all a little loose (tap the stator about with a rubber mallet if it isn't central) then nip it down properly and remove the shims.

[French MK]

Ok centered the stator using some shim. No mess at all there.

Now before i go through every check again.

when the points are open on the cam, I can open them more by moving the cam with my fingers sideways... almost but not quite doubling the gap.
There is no horizontal movement or up and down, just that sideways movement which i can push.

But then again when i turn the stator/rotor with a socket the gap stays as it should..... then again thats no momentum really i suppose.

[AzCal Retred]

Point gap is 0.012" - 0.020" maximum open range, yes?

[French MK]

I am using a Lucus key at 0.4mm / 0.016".... yes max

[AzCal Retred]

Sounds great. I run maybe 0.025" myself, but I don't spend much if any time at "high RPM" (>4000). Larger gaps are easier for olde eyes to see.

Point surfaces need to be clean & dry, no "engineers" clinging around the contact edges. Rubbing alcohol & thin brown cardboard strips (cereal box & similar) do an adequate job of scrubbing off oily carbon & the like. Contact cleaners are good, but often a film remains.