No Sprks from Coil

[haystax]

Hi,I am Kev,and new to this forum,and would apreciate a little help.I have just replaced cylinder heads after head gasket blown,and have replaced the Coil,as broke pins of old one...Now I cannot get any sparks at all..It has an Electronic Ignition,3 wires to a remote module,new spark plus and coil...It ran and started fine before...Is there summat i may have done wrong?

[haystax]

I forgot to mention,its a 3.5 v8 rover engine in a trike...

[Bryan]

Did you do anything to the distrbutor while doing the rest of the work? If not, this seems a bit strange. Occasionally you can get a faulty coil. simplest check is the DC resistance across the LT terminals - generally between 1.5 and 3 ohms depending on the coil.

When you changed the plugs, did you definitely reconnect them to the correct leads? I've got this wrong before and it can give the same symptoms as no spark.

Final thing that I can think of - did you replace the coil with a direct equivalent? If you have replaced a ballasted coil (usually 6V) with a 12V unit, the spark will be too weak to start the engine (and in daylight, it can be too weak a spark to see) Conversely, if you have replaced a 12V coil with one for a ballasted system, you may have overloaded the electronic system

[ramon alban]

Hi,I am Kev,and new to this forum,and would apreciate a little help.I have just replaced cylinder heads after head gasket blown,and have replaced the Coil,as broke pins of old one...Now I cannot get any sparks at all..It has an Electronic Ignition,3 wires to a remote module,new spark plus and coil...It ran and started fine before...Is there summat i may have done wrong?

Hello Kev, The most likely cause is that you have somehow introduced a connection problem or the circuit is now wrongly wired, so the system cannot function.

To verify the coil is OK, you can check it out independently as follows:

# Remove the king lead from the distributor.

# Attach a spark plug to the lead and lay it on a metal part of the engine.

# Locate the White/Black wire from coil negative to the amplifier and detach it from the coil.

# Connect a flying lead to coil negative

# Switch the ignition on and check there is 12 volts at coil positive.

# Briefly touch the free end of the flying lead to earth.

# Good spark indicates the coil is working correctly.

# Weak or absent sparks means the coil may be faulty to be exchanged or replaced.

If the coil is good but your system still will not function correctly then you need to review everything.

Read through both of theses articles but particularly the second one to test all the components individually and independently.

http://www.vintagemodelairplane.com/pag ... ion01.html

http://www.vintagemodelairplane.com/pag ... ion02.html

[haystax]

Thanks People for the Replies...I have a funny feeling that I may have replaced coil with the wrong one..The Coil does spark if you test it out of circuit....I have a spare distributer (DLMN8),with amp on side of it....it has a three pin socket on it...Every diagram i have seen,seems to have 2 wires coming off it....is there a diagram available to show how to wire up the coil circuit,and replace what I have now.....As my old dizzy has 2 wires out of it to a remote amp on frame...I appologise if I sound obscure in my Description.....?Kev

[ramon alban]

I'm not sure, Kev, but I seem to recall some one describing only two of the three pins are necessary for the circuit to work.

I think you can get an adapter from three to two pins.

Have a look inside the dizzy to see what is connected.

[DaveEFI]

The three pin amp for the DLM series is just a later version and is interchangeable with the two pin one. The third pin isn't connected - just a termination point for a screen. Lucas supplied these as replacements for the two pin version complete with plug and wiring diagram.

[haystax]

Thanks everyone for yer help....Got sparks now,just wernt in right place.....Running allbeit a bit rough...But its a start...A couple of teething probs,but got it it Running..Will kee ya's informed....All the Best