The Devil's in the Dizzy for the Vicar's Moggie

[mickeytwonames]

Trying to get the Vicar's moggie started after 4 years on blocks.
Got a big fat spark at the new points.
Coil bangs out a fat spark from the HT lead when earthed
Tried two different sets of leads and dizzy caps ( copper/carbon - side and top entry.
Tried two different rotor arms with both sets of leads but can't get a spark to the plugs (a newish set).
Any bright spark got any bright ideas that might get a spark?
Hero's ovation if you have.
Mickey

[Jefftav]

There is a small earthing wire inside the dizzy which can break? Or try a good distributor from another Minor to see if this makes a difference. A few years back there was a bad batch of rotor arms being sold so you might just be unlucky enough to have 2 of these(just a thought).

[bmcecosse]

It must be in the rotor arm/dizzy cap/leads.. Keep looking.

[Chipper]

Check the engine-to-body earth strap is securely fitted and in good condition.

[bmcecosse]

Is the little carbon brush (+ spring) present in the dizzy cap?

[katy]

Got a big fat spark at the new points.

That's quite often a sign of a bad condensor.

[bmcecosse]

But it's sparking at the HT lead ok......

[beero]

A set of these might help you diagnose it. Sometimes hard to distinguish a spark at the plug.
http://www.halfords.com/motoring/garage ... ark-tester
Are both sets of leads/dizzy/rotors new or old?
Check all your plug lead to dizzy connections and all your plug lead to plug cap connections. Test your copper leads for continuity, forget the carbon ones, they can be troublesome if they are old. It is possible both dizzy/lead sets have a problem.

[Chipper]

I would suggest that if you've got a decent spark at the king lead, and have tried two different sets of rotor arms and HT leads, then maybe the spark plugs themselves may be at fault, even if they are a newish set - try a different set...

I suppose another possibility is that the cylinder head isn't earthing via the engine block somehow - try connecting a jump lead between the cylinder head and battery earth.

[bmcecosse]

I did have an experience when a set of NGK plugs in mate's MGB refused to start. Threw them in the field and fitted an old set of Champions and it fired up right away.....

[chickenjohn]

NKG's are just as good as the Champions. Depends much more on the condition of the plugs than the brand. I use either on my cars and have found NO difference in reliability / performance.

As for swapping leads and distributor caps, rotor arms etc you do not say if these are new items. Possibly the second hand items you tried are also old/ faulty. Try a new set of leads, distributor cap and rotor arm, these are not expensive items.

Also check the plug lead order and ensure no1 of the 1,3,4,2 is no1 on TDC and not another position! You could just have the leads moved one or two positions round.

[katy]

I've had problems previously w/old plugs that wouldn't fire. The vehicle had been sitting for a couple or a few years, not sure how long, wouldn't fire at all, replaced the plugs w/a known good set and it fired right up. After the engine (a V-8) was warm, replaced 4 of the plugs w/the originals, it started and ran very rough for a few minutes and then settled down as the old plugs started working. When it was running properly again I replaced the other 4 plugs w/the originals and went through the start, run rough, settle down stages again. It ran well after that on the original plugs.
Your mileage may vary.

[bmcecosse]

The NGKs were brand new......the owner of the car neglected to tell me he had changed the plugs...he just asked for help because the car wouldn't start... Basic mistake by me....note to self - when attending a non-starting car - always check what has been done to the car!

[TFM150K]

A week on from the last post - the obvious question has to be "Is the vicar still on the bus or has the Moggie responded to all our prayers (and/or advice)" ?

[mike.perry]

Are the insulators on the points in the correct positions so that the points are not shorting straight to the distributor body?
Try turning the engine over on the starter in the dark and look for any stray sparks