Accuspark ignition woes

[TR Rob]

I have installed an Accuspark module to my Lucas distributor, prior to this the car 1960 TR3A was a good starter and ran well. 
As part of the installation I set the engine to TDC on No1 cylinder, removed distributor cap and red rotor arm, as expected, was pointing at No1 cylinder. Took points out, and carefully mounted sensor and ring as close as possible but not touching. Car is negative earth so from the distributor black wire to negative coil terminal and red wire to positive.

I then started the engine which while cranking on the starter motor the engine is firing, when you release the starter the engine dies.

I have tried retarding and advancing the ignition up to  10 degrees either way with absolutely no improvement , firing on cranking and then dies.

This is very frustrating and I am nearly at the point (no pun intended) of replacing and living with my old points.

Anyone on here experienced a similar problem and if so what or where am I going wrong

[Lebro]

well from your description you have done nothing wrong. very odd that it fires while cranking, but does not run.

I have fitted Accuspark in the past, & have had no problem, a very slight change in timing position was noticed, but not enough to stop it working. May be worth checking that the thin earth wire from distributor body to the moving part (top plate) is ok.

The Accuspark module I used is now fitted to a Triumph Herald, & is still working fine. (I moved over to Pertronix on advice from Martin (Distributor Doctor) but have noticed no difference.)

Maybe it's just a faulty module ?

Bob

 

[RobH]

Having read the fixing instructions, I note they say the pickup in the distributor must be earthed and that excessive heatsink paste can hinder that.  It would be worth checking that the earthing wire to the baseplate is intact as Bob says, and that the module bracket is making decent contact to the plate. 

(see my direct e-mail re the possibility someone might have fitted ballasted ignition)

Edited November 13, 2023 by RobH

[Lebro]

Ah,ballasts ignition - that would make sense of it all, not enough volts for the module when cranking stopped. Well done, wish I'd thought of that.

Bob

[TR Rob]

I have checked the coil and it is not a ballasted version.

I thought that initially and tested the coil across the +\- I got 2.9 ohms and the coil output was 8910ohms

Update…..as a precaution against head failure I bought two of these units one to carry as a spare. I fitted the spare one and the car started like a dream, set ignition up using a strobe and took car for a drive, ran very well.

Got back to garage , tidied up wiring, let engine cool down and decided to restart engine ….same old problem cranked and fired then died. 
That was it for me no more electronic stuff, cleaned up points, which are new , refitted, new set of plugs, quick run over with strobe and engine is running better than ever.

So as Rob emailed me a few days ago, for the few miles I do a year and a bit of adjustment now and then I am sticking to the good old points. 
One positive thing Rob, out of this, is I have got rid of yet more PO adhoc wiring !!

 

[RobH]

Glad you have sorted that Rob but it is strange that both modules seem to have failed.  I wonder what they don't like?

I note that Accuspark say:   

" Check the charging system; with the engine running the battery voltage should not exceed 14.2 Volts. If the vehicle is over-charging, a new alternator or voltage regulator will be required. Over- charging will damage the AccuSpark unit.

http://www.accuspark.co.uk/fitting_guide.html

 

[Lebro]

Unlucky, I think you should check you charging voltage.

Bob

[BlueTR3A-5EKT]

I had to retime by best part of 15 degrees to get mine to run when switching from points to electronic.   

[Nigel C]

I too have fitted one of these and carry a spare. the one fitted has worked well for sometime now (DOH, here we go) and I have not used the spare but you have me thinking now is it any good. Perhaps I should swap it over to check instead of having to rely on it one day and it not perform.....

[Andy Moltu]

Retro fitting a ballast system would be unusual. But your issues fit with a failing ballast resistor. Ie the coil gets a live feed when cranking but nothing when the key is released.

Do you get a 12v reading at the coil when the ignition is on?

[John McCormack]

I fitted an Accuspark to my daily driver TR2. It failed shortly after fitting. They sent me a new one free of charge. It failed to.

My car runs a generator and the Accuspark distributor said that is probably the problem. The Accuspark will fail if it receives more than 14.2volts. A generator can put out a lot more than that when the battery is a bit down.

I now have Lumenition and Pertronix in the cars.

Edited November 15, 2023 by John McCormack

[TR Rob]

Quick follow up on ignition issues. Having replaced my AccuSpark unit with my original points system, my car ran perfectly. However on a subsequent test run the car broke down , in that it would not restart after a brief visit to the Post Office ! 
It was same problem firing on the starter motor and then dying. 
Turned out to be the white cable to the positive side of the coil, while superficially appearing to be connected, 63 years of vibration, hot and cold conditions the cable was partially fractured at the crimp point hidden by the insulation cover. 
Cable now cleaned up and a new terminal crimped on seems to have solved problem . 
Ironic that this happened while trying to do a conversion on the ignition system, but more than likely that working around this area has exasperated the wear on this terminal, decided to stay with points !!

[RobH]

2 hours ago, John McCormack said:

My car runs a generator

/pedantic mode ON

Just to clarify - I understand that down under and elsewhere, generator is widely used to mean a dynamo. That didn't matter when only dynamos were around but can cause confusion now, since in Blighty 'generator' is really a generic term for any machine which produces electricity. Both dynamos and alternators are 'generators'.

The voltage control on a dynamo is poorer than for an alternator because of the electro-mechanical nature of the control box. Under certain circumstances a '12v' car dynamo can put out up to 15 volts while most alternators control at about 14.7 maximum but these are open-circuit voltages with the unit not connected to a battery.  

The highest voltage measured on the car is not really determined by the generator but rather by the state of charge of the battery when the engine is running.  A plain lead-acid battery can reach 14.1 volts when fully charged and receiving a trickle from the generator (2.35 v per cell).  Lead-acid "calcium" batteries are now commonly sold and many people use them in classic cars. These have a chemistry which results in a slightly higher cell voltage, and the voltage on the car may reach 14.5v .

/pedantic mode OFF

 

 

Edited November 15, 2023 by RobH

[Lebro]

Seems a shame to condem the Accuspark modules now you have found the real problem.

Just my opinion.

Bob

[TR Rob]

2 hours ago, Lebro said:

Seems a shame to condem the Accuspark modules now you have found the real problem.

Just my opinion.

Bob

I agree . However there are many comments on this site both for and against the benefits of electronic ignition and many comments referring to the failure of AccuSpark products. I considered all these comments in my decision to change from points to the AccuSpark product. What I hadn’t sanctioned for was in fitting this product  a consequence  would be the failure of something as basic as a terminal connector.

With hindsight I owe an apology to AccuSpark but I feel faced with the facts my initial comments were justified, being based on other forum members experience of AccuSpark product failures.

In conclusion I will not be refitting the AccuSpark product as after this debacle I have now become expert at fitting, adjusting and maintaining a points based ignition system…. period

Edited November 15, 2023 by TR Rob
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