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MGB Stupidity.

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I will dissemble the points and reassemble looking hard for any place its grounding. I tried to look yesterday just for that, i must have missed something
 
Have you checked the points with a volt/ohm meter? Disconnect the wire from the coil and check for continuity between the point surfaces when open and when closed. You should have continuity when closed, but not when open. If so, then it's a ground issue - either the condenser is shorted or the wire coming in from the coil - a usual suspect as stated above.
 
thats a good way to test it. thank you, i would have been flying blind. the ignition is a new experience for me.
 
continuity perfect when points touch. As soon as they separate the needle drops to zero. Meaning no grounding issue correct? Or am i being over zealous here?
 
TOC said:
Okay...no power at the coil with key on. NOT the points or coil if you have no power on either coil primary wire.
If you have power to one side of the coil, disconnect the wire to the distributor and then, with it safely out of the way, key on, check for power on the end of that wire.
If you have power, you may have mis-assembled the points.
Seen it done.
If any of the bits are on the ground side of the insulator, it will act like the points are closed, and there will be no power out.

Now, do you have power on either of the coil primary wires?
If so, with the wire to the distributor removed (and you can do this at the distributor...only reason I have you check ay the end it to make sure that wire has not failed) do you have power at the end? Do you have power at the other end where it connects to the coil?

Report back and we'll go from there.

Dave
Click to expand...

Time to check part two (in red) of Dave's suggestion, if you haven't already. Also, check to make sure you have power coming into the coil from ignition switch (positive terminal of the coil).
 
My apologies, wire from coil to distributor was still connected. with is disconnected there is continuity no matter the placment of points, both open and closed.
 
There is power on the positive side of the coil with key on. No power in wire from distributor to coil though. Either end of the wire or the spade from distributor.
 
Mickey, i cant thank you enough for going step by step with me here
 
OK. With the distributor cap off and the wire from the coil disconnected, check for continuity between the body of the distributor and the terminal on the side. You should have continuity with the points closed, but not when they're open; if so, then the likely culprit is the nylon/fiber/plastic washer that is supposed to isolate the path.
 
Looks like you posted while I was typing that last message. If you have 12 volts coming to the coil, but not out, then it sounds like a dead coil.
 
Quick coil test:

 
All i did was test the positive side of coil with key on. Not that this means anything but the coil is a new one from napa. Though it did pass my bench tests. With the coil disconnected There is no continuity from one side of points to the outside of distributor. There is on the other side. This is normal?
 
I am getting continuity from the distributor body to the connecting for the coil wire. this means Im grounded somewhere. I just don't see where.
 
Most likely either the isolating washer/grommet at the terminal, or the nylon "bearing" the point spring rests on. Or the condenser is shorted.
 
the condenser i never switched out hearing they just about dont go bad from a few sources. Anythings possible.
 
Points connected or separated there is solid continuity between the body of the distributor and the coil wire. The rubber grommet under the wires inside looks solid. where is this nylon bearing?
 
WillR said:
Points connected or separated there is solid continuity between the body of the distributor and the coil wire. The rubber grommet under the wires inside looks solid. where is this nylon bearing?
Click to expand...

Check the image below - white nylon bushing on the left where the curved spring is attached. Usually in two pieces - upper and lower - isolates the spring/contact point from the base.

lucas points.jpg
 
the napa part i have it looks like one peice the runs down that shaft and opens up at the top to stop contact from the "eyes" of the wires inside
 
As long as the spring and wires are isolated from the curved base, and its post, you should be OK. But that's a common culprit for unintentional ground. The wires should be "riding" on the nylon/plastic/fiber piece so that they don't touch the post. Hope that makes sense.
 
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