How to test the points and ignition coil..be patient with me

[holymoly]

Hi guys,

Newbie mechanic here...but basically I bought a CA77 in pretty rough shape. I replaced the battery, checked the fuse, and I'm not getting any spark. From spending the better half of the day searching the forum, I'm assuming that I need to test the points and the ignition coil.

My question is...can someone describe how to exactly test these? I have a multimeter, but I still cant seem to figure it out/

Additionally, any possible ideas what else the issue could be? Starter switch?

p.s. the button from the stater switch is gone...so im only using the kick start (not sure if that helps or not).

[e3steve]

Welcome along. You'll soon be as bonkers as most of us, rest assured!

Easypeasy:

Basic test -

• Remove both plug caps from the plugs and unscrew both plug caps from the HT leads
  Remove both alternator cover (engine, r/h/s, 3 screws) and points cover (cyl head, r/h/s, 2 screws)
  With a spanner or a 14mm socket, rotate the rotor (the magnetic bit with the timing marks on the crankshaft) until the points close
  Turn on the ignition (good battery?)
  Hold each HT lead, in turn, with the copper core about ⅛" from a cylinder head fin -- wear a pair of gardening gloves, unless you get your kicks from licking power outlets -- and rotate the rotor until the points open

As the points open you may get a little spark from them but you should get a good, meaty spark from the HT lead across to the fin

G'luck!

Steve

[marzini]

Thanks for the tip E3! Cheers— Mar'

[67305dream]

The path of current is from ground (which in this case will be the cylander head) up though the points, through the coil, through the ignition switch then to the battery. So take the points cover off turn on the igition switch on, put a voltmeter (black to cylander head) (red) to the leafspring of the points. If the points are open, you should read 12 volts here. With the points closed it should read 0 volts. If you have 12 volts with the points open then your ingition switch and coil are conducting and your problem is likely your points. If you like, you can go the other direction. Make sure you have 12 volts at the battery, then at the switch, then at the coil IN then the coil OUT (NOT the high voltage out but the other small wire) and (assuming the points are open) 12 volts at the points. If the points are closed you should have volage everywere but the points and the above mentioned coil OUT. If this is confusing, I can email you a little diagram, might make it easier to understand.
Hope this helps!
Path: BATT->Switch->Coil->Points->Cylander head.