Hi,
I was involved in a mid air yesterday, and sustained damage to the ignition unit. The wire leading from the pick-up to the ignition module was severed. (See picture). Having opened the unit, i can see that there are three wires, white, brown and green. The white one is still attached to it's original solder point on the circuit board; the green and brown came off from the solder joint. I assume that they came off the points right next to the point where the white one is attached (right next to the electrolytic capacitor).
Am I correct? Am I also right in thinking that the green wire goes to the point closest to the capacitor, and the brown one to the other?

I understand that any repairs done by me would not be warranted in any way, but I feel that I can repair it, if I know where to solder.


Thanks in advance

check the shape of the severed joints. They should about match up, and you know what goes where.

Can someone take the cover off theirs and give the poor chap a picture?

Mike

Thanks for the response Pe. I could not tell from the shape, where each of the wires go; I am only relying on my intuition. I have soldered it now, and will try out the ignition unit when I get the chance.

Yeah that would be brilliant if someone could do that!!! I have looked on the internet hoping to find a circuit diagram of some sorts; also spoke to the MVVS distributor in the UK (a very nice chap by the way), but they do not repair the modules. He says even MVVS does not repair the modules. Advice is to replace it, which is what I will have to do if the repair is unsuccessful. However, if I can get a picture of the internals from someone with said module, that will certainly help.

If you are going to buy new I suggest you investigate the new automatic choke version, I find it works absolutly fine with no problems, Pe Reivers would have all the information you need, unfortunatly as much as John of Puffin models is a nice chap he would not know if the ignitions where compatable with the Evolution as he has only just taken over the MVVS distributorship and before that was electric only.

Mike

Thanks a lot for the suggestion, Mike. I actually, I have looked at the option, but the spark plugs are different. So perhaps that would also require a new cylinder head.

I doubt it, a spark plug of any size only requires a timmed voltage to fire it, I don't think the size will make any difference, ask Pe by a PM it will get to him quicker as the moderators on this Forum do not seem to be receiving notifications of postings.

Mike

Hi Mike,
The problem is not with the voltage to fire the plug, but rather with the threads the spark plug screws into. The old style had M14 threads and the new one is M10.

Understand, I wonder if there is an insert you could put in like a Helicoil you have 2mm clearance all around, again ask Pe Reivers he would know.

Mike

http://www.v-e.cz/ign_1ti.php

You can ask here.

I have made some plug inserts. MVVS also makes them by now. You also would need a different prop drive washer, because the latest ignitions have the magnets at 120 degrees, and not 180 degrees like the Vlach units.
It would be most convenient to get a new Vlach unit.
I must check if I have an opened unit arouns somewhere, and take a picture. That may help you to reconnect the sensor.

Thanks for the offer to help. I already tried soldering the wires where I figured they belong, but no joy. I get the one spark when connecting the battery, but nothing when flicking the hall effect switch over the magnet. I even swapped the green and brown wires, no change. So it appears that there was other damage somewhere in the unit.
I eventually got myself a brand new Vlach unit.

Just for your information the Hall effect sensor needs two magnets to pass before it will fire the plug, on the new units this is at 120deg so it can tell if the engine has started backwards and shuts down the unit before any damage can be done to the reed valves, so I have been informed.

Mike

Really!! So perhaps the unit I have is still working! Well I guess I will mount the engine on a stand when I can and test it. I guess that is why I did not get the spark.
Thanks for the information.