- Fri May 18, 2012 11:33 pm
#483
Had another bash at the electrickery today as it was dry.
The mystery red/black wire looks to be the -ve from the coil via the engine kill switch, which explains why I couldn't find the other end as it's in a box that the eureka igntion came in, and also why the kill switch makes no difference to the running of the engine.
Checked the feed at the coil, voltage at the +ve side earthed to frame with ignition on, same at the -ve side ignition on, I thought this would change at some rotation point as the LT circuit dropped the power and it transferred through the HT circuit?
Re-checked cleaned and refitted the earth to the eureka unit as it was a little loose anyway.
Checked continuity through the coil cap, ok, ht lead, ok, plug cap, not OK, ah-ha, I thought, tried a cap from a project bike sitting in the shed which I know to work, still not firing, then I found a couple of old, (unused), champion short reach plugs from the 2CV6 I had, tried one earthed against the head, seemed to get a spark albeit weak, whipped out the old plug to try this one just to see if it would fire and the threads i'd been very carefully nurturing since discovering the plug hole had been cross-threaded gave up it's grip on the last few bit of thread in the ally, I can only assume the new plug threads were just too much and the sealing washer wouldn't compress before the threads gave.
So now i'm back to the take off the head to helicoil it scenario I'd anticipated on first discovering the cross-thread, quite annoying as the previous owner must have known about it.
If it's decent dry weather again tomorrow i'll see about getting the head off and need to add a head gasket to the hitchcocks order, good job I haven't put it in yet.
Frustraing, seems like 1 step forward and 4 back at the moment
The mystery red/black wire looks to be the -ve from the coil via the engine kill switch, which explains why I couldn't find the other end as it's in a box that the eureka igntion came in, and also why the kill switch makes no difference to the running of the engine.
Checked the feed at the coil, voltage at the +ve side earthed to frame with ignition on, same at the -ve side ignition on, I thought this would change at some rotation point as the LT circuit dropped the power and it transferred through the HT circuit?
Re-checked cleaned and refitted the earth to the eureka unit as it was a little loose anyway.
Checked continuity through the coil cap, ok, ht lead, ok, plug cap, not OK, ah-ha, I thought, tried a cap from a project bike sitting in the shed which I know to work, still not firing, then I found a couple of old, (unused), champion short reach plugs from the 2CV6 I had, tried one earthed against the head, seemed to get a spark albeit weak, whipped out the old plug to try this one just to see if it would fire and the threads i'd been very carefully nurturing since discovering the plug hole had been cross-threaded gave up it's grip on the last few bit of thread in the ally, I can only assume the new plug threads were just too much and the sealing washer wouldn't compress before the threads gave.
So now i'm back to the take off the head to helicoil it scenario I'd anticipated on first discovering the cross-thread, quite annoying as the previous owner must have known about it.
If it's decent dry weather again tomorrow i'll see about getting the head off and need to add a head gasket to the hitchcocks order, good job I haven't put it in yet.
Frustraing, seems like 1 step forward and 4 back at the moment