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Well, i have just borrowed an amplifier and still no spark. This calls for serious thinking........in the pub!

will go back to it in the morning to start looking through it all again. I suppose its possible borroed amplifier is also knackered. That would be unlucky

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Did you check the shaft on the distributor is turning when you crank the engine? If its not, there will be no spark. The distributor only needs to be a little 'out' for it to not engage properly. :)

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It's getting there......

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Rotor arm is turning

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It was working, you took it apart and put it back together, it's not working.  When in this situation my first thought is that everything's probably fine and I've made a mistake (perhaps distributor timing way out). So, have you confirmed categorically that there's no spark from the coil lead?  I haven't seen that in writing..?


British Ambassador to Florida, New York, Denmark and Newfoundland.  And Sweden.

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You haven't missed out simple things like checking the amplifier has a good supply and earthing?

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3 hours ago, ekwan said:

You haven't missed out simple things like checking the amplifier has a good supply and earthing?

Agree. Ground the AB14 seperately and test again


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13 hours ago, Sparky said:

It was working, you took it apart and put it back together, it's not working.  When in this situation my first thought is that everything's probably fine and I've made a mistake (perhaps distributor timing way out). So, have you confirmed categorically that there's no spark from the coil lead?  I haven't seen that in writing..?

Agree, because in your results from test 3 it suggests the amp is working. What this test is doing is trying to measure the averaged result of the low-going pulses from the amp output, in the absence of an oscilloscope. So when not cranking there is 12V on the LT of the coil, and when cranking there is 2 volts, which indicates the amp is pulsing this low, and working.  

So the spark from king lead needs to be checked, in case the distributor is out, causing the spark to happen when the rotor arm is between contacts.

BTW any update on that gearbox noise?

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16 minutes ago, Andyww said:

Agree, because in your results from test 3 it suggests the amp is working. What this test is doing is trying to measure the averaged result of the low-going pulses from the amp output, in the absence of an oscilloscope. So when not cranking there is 12V on the LT of the coil, and when cranking there is 2 volts, which indicates the amp is pulsing this low, and working.  

So the spark from king lead needs to be checked, in case the distributor is out, causing the spark to happen when the rotor arm is between contacts.

BTW any update on that gearbox noise?

Depending on how far out your timing setting, I would have thought there would be backfiring through either the exhaust or carburettors. At least, there might be vain attempts to fire up.

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Sparky. Definitely no spark from distributor lead at the moment. Wouldnt i get a spark even if timing was out even if its at completely the wrong time?

Gis. I have runna seperate earth direct to battery terminal. No joy

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Not necessarily.  Check spark first at the coil lead.


British Ambassador to Florida, New York, Denmark and Newfoundland.  And Sweden.

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Andy. Im a bit lost to be honest. Will go back out there this morning and run through it all again looking for stupid mistakes. 

Dont ask about gearbox. That car is sitting with no gearbox at the moment. Im afraid working (Often away) doing an old house up, life in general and try to get 2 Esprits running has proved too much. Deal is get the no spark car running on the road, re do dining room(Major task) then go back to gearbox issue 👍

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Sparky. HT lead from coil is disconnected from dizzy and held a few mm from gearbox bellhousing. Turn engine over. Nothing. No spark. If speed of turning engine is slowish would this alter anything. Could try jumping from a running car

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Certainly give it all the help you can, if your battery is low.


British Ambassador to Florida, New York, Denmark and Newfoundland.  And Sweden.

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If you have a multimeter, disconnect the 2 wires running between the distributor. Measure the resistance across the 2 terminals distributor side. You should get a resistance reading around 2.2 - 5 kOhm.

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The symptoms indicate the coil, although its impossible to be sure because that test 3 is relying on the result of averaging the LT pulses. Cant be 100% sure there are actually pulses there without a 'scope.

What is the history of the coil, has it been replaced? Note there are many websites which suggest testing a coil using resistance checks. Ignore these because if the coil has a partial short between windings this will eliminate the voltage and cant be detected using a resistance test. 

For some reason the tests use 12V as a reference, not sure why, but you could double check by connecting black probe to chassis instead and check for 12V on the + of the coil and that the - of the coil is dropping when cranking.

2 minutes ago, ekwan said:

If you have a multimeter, disconnect the 2 wires running between the distributor. Measure the resistance across the 2 terminals distributor side. You should get a resistance reading around 2.2 - 5 kOhm.

That was already done, 3.4 K 

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8 minutes ago, ekwan said:

If you have a multimeter, disconnect the 2 wires running between the distributor. Measure the resistance across the 2 terminals distributor side. You should get a resistance reading around 2.2 - 5 kOhm.

3.4 ohms

 

 

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3 minutes ago, Andyww said:

The symptoms indicate the coil, although its impossible to be sure because that test 3 is relying on the result of averaging the LT pulses. Cant be 100% sure there are actually pulses there without a 'scope.

What is the history of the coil, has it been replaced? Note there are many websites which suggest testing a coil using resistance checks. Ignore these because if the coil has a partial short between windings this will eliminate the voltage and cant be detected using a resistance test. 

For some reason the tests use 12V as a reference, not sure why, but you could double check by connecting black probe to chassis instead and check for 12V on the + of the coil and that the - of the coil is dropping when cranking.

That was already done, 3.4 K 

Did he also put a meter across the said terminals when the engine is cranking, just to see if the reluctance sensor is triggering.

 

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1 minute ago, ekwan said:

Did he also put a meter across the said terminals when the engine is cranking, just to see if the reluctance sensor is triggering.

 

Do you mean across the terminls where i measure 3.4 Ohms?

Andy. On second coil. Have a 3rd i will try today

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28 minutes ago, PhilW said:

3.4 ohms

 

 

Thats the problem then. It should be between 2000-5000 ohms! I assumed the 3.4 in test results was 3.4 K ohms not 3.4 ohms.

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1 hour ago, PhilW said:

I have runna seperate earth direct to battery terminal. No joy

Did u run that ground lead from the edge of the fibre glass box cable connection or from the AB14 directly? The AB14 is held into the fibreglass box with some screws that run through its body. I assume you have the boot floor out, just put the whole box on top of the rear crossmember and make sure the AB14 screws touch the metal. Simple test. I had a no spark situation a year ago and it was a shaky ground connection. Sat the whole box back on the cross member. Voila. Spark


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7 minutes ago, Andyww said:

Thats the problem then. It should be between 2000-5000 ohms!

Yes in the 000's of Ohms range.

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Sorry. 3.4k ohms. Just rechecked

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Gis see what you are saying but i ran lead direct from mounting bolt to batter negative and acived nothing. 

Andy. Have 12 volts between battery + and gearbox bellhousing. When i crank engine volts on coil negative drop to 6-8v

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What about voltage on the coil + when cranking?

It might be dropping to the same, owing to load caused by the starter. The important factor is whether the voltage on the - drops with respect to voltage on +. 

 

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31 minutes ago, PhilW said:

Sorry. 3.4k ohms. Just rechecked

When you crank the engine, that should go up and down. Did you check that? That will tell you the pick-up is triggering, and eliminate that once and for all. Then we can look at other things.

 

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