No Spark :(

[red vtec]

It looks like I have no spark from the plugs since replacing the dizzy cap and rotor arm. Which is a bit of a bugger!

Could this be caused by having the timing way off? I have rechecked the rotor arm, dizzy cap, leads etc this morning.

I'm learning as I go along.

Thanks

Chris

[rogerch]

The timing will not effect the performance of the spark, only when it happens. Back to the start, take the coil lead off the distributor and try to start the motor with the lead held (insulate your hand) near an earthing point, the spark should jump the gap, from your prior posts I believe it will. Then you will have proved the spark is getting to the distributor. Is it a new cap? You have had the cap off so something has gone awry since. Is the plenum off, if not, sorry take it off, one of things that is difficult is to get the cap aligned properly, any doubts and you need a visual check, let us know.

Roger

[ramjet]

Chris,

Even if the timing is way off, you will still get a spark. It just may be at a time when the engine simply won't fire. However, unless you actually moved the dizzy everything will still be in the same spot so the timing should not have changed.

There is a small wire that runs through the dizzy body, well there has been on every dizzy car I have ever owned, so I don't think it will be different with a lotus. If you have dislodged the wire that connects to it outside the dizzy when replacing the arm and cap, that'll certainly stop your spark. The other thing that can catch people out is the lead from the coil to the dizzy cap centre. You mat have replaced it correctly on the cap but if you have pulled on it at all you may have broken the connection back to the coil. Check that too.

How do you know you have no spark? Simply because the car won't start? Have you put a spare plug in a lead and earthed it to the block and watched to see if it sparks when the engine is turned over?

Michael.

[cjtpb13]

Chris,

Once you prove that the coil has power ( utilising Rogers method ) and that it is coming to the distributor. next would be to check that with a lead on a plug but the plug out and touching an earth source that you get a spark across the gap. Mind your hand. Lots of voltage but low amps if you get zapped so no damage done. At first use a source of earth other than the engine. if that works then try the engine as the earth source. Recall that 80% of electrical issues are earth related not positive like most people believe.

Sure you are very frustrated at the moment but step back and take a moment. very simple electrical circuit. Break it down. Also check all of your positive and earth connections from the battery to the coil. I have seen cases ( ironically in a Honda Prelude ) where the main lead on the battery was half split thus causing an intermittent issue. TIming being off would only cause a misfire not a lack of spark.

[Simon350S]

is the 2 pin plug from the distributor to the ignition still connected?

Its easy to knock this appart when fiddling with the distributor and is the most likely suspect considering....

Check it and report back

[lotus4s]

Check your pickup coil in the distributor, it can cause the symptoms you describe. Due to the plate it is mounted to moving back and forth when the vacuum advance/retard operates, the wires to it are constantly flexing and can be broken internally.

You can see another owner's write-up about it here:

clicky

Edited June 12, 2010 by lotus4s

[cjtpb13]

Chris,

Always a great and knowledgeable group here...makes it a great place.

As discussed on the phone earlier here is the link to help you learn a bit more on automotive electrical.

basic automotive electrical fundamentals

This gentleman does a great job in his explanations of things. Was helpful to my brother. That way he could understand half of what I was talking about too!

[fesuvious]

Happened to me once, on a Rover V8.

went round checking all leccy connections, earths, double  checked my marks for timing, spent all afternoon looking over

Then a mate came round and solved it

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forgotten to put the rotor arm back on!!!!!!!! so obvious, so blindingly obvious, I didn't see it DOH !

[red vtec]

Thanks for the replies,

After speaking to Christopher (sorry about that my friends turned up with two youngsters in tow), I have followed Rogers advice and tried to see if I have a spark from the coil it would appear not I think this could be the problem.

I pluged a spare HT in the lead and a spark plug that I earthed back to the battery and could not see a spark, So looks to me like the coil has gone. Looks like it may just be coinciedence.

Does this sound right?

Thanks

Chris

[Sparky]

Wild stab in the dark - you haven't perchance pulled the dizzy out a little, thereby disengaging it from its drive? Seen it happen many a time.

[cjtpb13]

Chris,

I hope you have a multimeter or what I call an Ohmmeter...if so make a quick check...all lines removed from the coil...check the Ohms resistance between the two side terminals, this is measuring the resistance of your primary coil.

It should read between 0.75 - 0.81 Ohms

Next measure the Ohms resistance between either side terminal and the HT centre terminal, this is measuring your secondary coil

It should read between 10,000 and 11,000 ( 10K-11K ) Ohms

If not you have definitely ruled a bad coil. And yes most likely if that is the case it is pure coincidence.

And no worries on the friends showing up in midst of the call. I am sure you expected them and my call was unexpected...

[andydclements]

How about faking the amplifier and simply connecting and disconnecting the LT side of the coil by hand, does that generate a spark?

[red vtec]

You can all sleep well, now the nights of you worrying over my issue and not being able to sleep are over.

Sparky was correct the drive shaft for the dizzy had become dislodged, it is a terriable placement and a complete pain to change, fit and time up but I have now done it, it is now bang on.

I found a large selection of swear words was the best tool. I have now arranged a hit on the engineer who placed the distributer in its location.

Thanks for all the help on here and on the phone

Chris

[rogerch]

See it's called a rotor because it's supposed to rotate

All hail the great sparky

Glad you found it, get some sleep.