points will not spark

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dellerie
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points will not spark

Post by dellerie »

i am struggling now with this and can't see the wood through the trees. i have come to a grinding halt in other words.

the car refuses to start. it turns over fine. fuel is getting through ok. the problem is 100% electrical. i have tried and tried to sort this, but have been beaten now. without help, i can't go any further.

when i switch the ignition on, i connect a multimeter to the live side (plus terminal) of the coil and also on the negative post on the battery. i get 12 volts. this is the plain white wire going to the plus on the coil. in my estimation, that means up to this, i don't have any problems. all other electrical items work fine. ok so far?

i then connect a wire from the minus terminal on the coil to the dizzy. i turn the engine over and i don't get the points sparking. without the points sparking, there is no point going any further. what am i missing?

i have put new points and condensor in, nothing.

i have tried fitting new dizzy with the red wire to the plus and blue to the negative on the coil. nothing.

where am i going wrong???? i can't drive my car and the MOT will need doing in a couple of weeks. i am in a rut here.

i have tried another coil (unused new) and that didn't give me a spark either. basically from the coil onwards, it's completely dead. i have checked, re checked and checked all the connections again and again and again.

how is the LT lead and condensor fitted. the round part of the points goes over that little post, with the white plastic piece in between. is there something not right there?
aupickup
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Re: points will not spark

Post by aupickup »

the plsatic washer needs to go on top
bmcecosse
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Re: points will not spark

Post by bmcecosse »

The points assembly need to be isolated from earth. Also check the little 'low volts' wire in the dizzy is not shorting. I assume there is a gap in the points....... I don't understand your 'spare dizzy' comment re red and blue wires.........is this a 'so-called' electronic dizzy ? also look to the HT side - is there a spark at the king lead from the coil??
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dellerie
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Re: points will not spark

Post by dellerie »

if i right here, with the cap removed, if i turn the engine over, the points should spark? they don't.

i have power to the coil, but the points don't spark
bmcecosse
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Re: points will not spark

Post by bmcecosse »

Only if the points have been assembled correctly....... Check the workshop manual section carefully for the correct assembly order.
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dellerie
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Re: points will not spark

Post by dellerie »

bmcecosse wrote:Only if the points have been assembled correctly....... Check the workshop manual section carefully for the correct assembly order.
i have gapped them correctly and the faces aren't pitted. 0.15.
MarkyB
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Re: points will not spark

Post by MarkyB »

Try drawing a piece of card between the closed points, some have a protective oil on them which isn't conductive.

"Once you break something you will see how it was put together"
dellerie
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Re: points will not spark

Post by dellerie »

MarkyB wrote:Try drawing a piece of card between the closed points, some have a protective oil on them which isn't conductive.
thankyou. that sounds like my 1st job in the afternoon. never knew that.
beero
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Re: points will not spark

Post by beero »

If you have a multimeter connect it to the wire from coil to dissy and see if it is earthed when the points are closed and open circuit when the points are open. This will prove whether you have assembled the points properly.

bmcecosse
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Re: points will not spark

Post by bmcecosse »

I doubt it's a surface problem - but no harm trying. As beero suggests - you must make sure the points are not shorting out - this is very likely to be the problem.
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kennatt
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Re: points will not spark

Post by kennatt »

also check that you hav'ent overtightened the nut that holds the points spring onto the peg it can cut through the plastic isolator and short everything out
dellerie
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Re: points will not spark

Post by dellerie »

ok then, if the points ARE shorting out, how would i overcome this problem a 2nd time? what do i need to do to avoid this.

thanks
mike.perry
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Re: points will not spark

Post by mike.perry »

Check the assembly of the points.
The spring should be isolated from the contact plate and the pillar. The low tension leads should fit over the plastic sleeve and be in contact with the spring but not the post or contact plate.
You should see a spark when you flick the points open with your finger nail.
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dellerie
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Re: points will not spark

Post by dellerie »

well gents, i have found out the problem. it was the plastic block on the side of the distributor. the wire must have seen better days. i assembled everything the way you people told me and added a new wire, as i found a new one in my workshop.

put it on and the car fired up :lol:

i took it for a drive but the only snag is when i press the clutch pedal, the rev's die slightly. it's enough to stall it at lights etc. why would this be?
aupickup
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Re: points will not spark

Post by aupickup »

increase the tick over slightly
dellerie
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Re: points will not spark

Post by dellerie »

aupickup wrote:increase the tick over slightly
is that the cure then? will it not run faster? it will surely use more fuel?
bmcecosse
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Re: points will not spark

Post by bmcecosse »

Or possibly the clutch is over-stroking. How much free-play is there on the pedal?

And - I did suggest checking the 'low volts wire' in my first post in this thread......... :roll:
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dellerie
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Re: points will not spark

Post by dellerie »

bmcecosse wrote:Or possibly the clutch is over-stroking. How much free-play is there on the pedal?

And - I did suggest checking the 'low volts wire' in my first post in this thread......... :roll:
easy tiger. i am new to this game. give me a chance!
bmcecosse
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Re: points will not spark

Post by bmcecosse »

:lol: :roll:
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dellerie
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Re: points will not spark

Post by dellerie »

bmcecosse wrote:Or possibly the clutch is over-stroking. How much free-play is there on the pedal?

And - I did suggest checking the 'low volts wire' in my first post in this thread......... :roll:
there is about an inch play in the pedal before pressure. biting point is halfway. i fitted a new clutch and thrust bearing a month ago. clutch operates fine.
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