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MGB '76 MGB ignition trouble

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distributor. Doc was the first one I ever heard use it a few years ago when I first joined and had a similar problem
 
Ha i just looked at youe location. My MG came from Ohio. Drove 11.5 hrs there in a jeep with a dolly. Napped for twenty min until it was time to pick up the car and go to the dmv with the owner then shot back to new york. Fun trip
 
I thought you were talking about a PART of the distributor... I am positive that the distributor I have in it right now is a working distributor. And I am positive my coil is good too. Unless something happened in the week I did not touch the car while it sat in my garage...
 
fireman91178 said:
I thought you were talking about a PART of the distributor... I am positive that the distributor I have in it right now is a working distributor. And I am positive my coil is good too. Unless something happened in the week I did not touch the car while it sat in my garage...
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Famous last words - "I am positive" are not good words for British Cars - don't ask me how I know ;) Now let's get back to sorting this out.
 
lol yup :iagree: they can be sneaky beasts
 
Okay. This ain't rocket surgery...

1) The WHITE/GREEN WIRE should be connected to the positive (+) terminal of the coil. That wire will only have voltage when the ignition switch is on. Check it with a test light, a V olt Ohm Meter would be better.

2) You have a Luminithion ignition set-up for triggering spark, they are notorious for failure, I'm surprised yours has lasted as long as it did. REPLACE it with a Pertronics set-up. What you have now.

3) If you are intent to troubleshoot it, THIS diagram is likely what is correct for your car, check the wiring you have against what is shown here:


iggy1.jpg
 
The wiring is all ran correctly according to the diagrams. If anything, I believe it would be a faulty wire somewhere. Test lamp lights on positive terminal of the coil with ignition "on". Negative terminal never lights test lamp. Distributor turns counterclockwise when engine is cranked.
Only time I can seem to get a spark at all is when the distributor is out of the engine...
 
Can you install the distributer backwards on one of these puppies? You can with a Midget 189 deg out
 
No, JP. The "dog" at the drive end is offset and will only engage fully with the shaft aligned correctly. Even if 180° out, spark would be evident (backfire, etc) if present.

As to the "test light never lights on negative coil terminal" statement: It never will with an electronic ignition, as one member pointed out a while back.
 
fireman91178 said:
Mickey, that just seems to go against what I've been told so far... Electronic is better...
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Not necessarily, depends on the situation. I had my distributor for the 72 rebuilt by advanced distributor and Jeff asked me if I wanted to go electronic? I asked what he would recommend and he said POINTS! that was 8 years ago and I only readjusted them once in that time. PJ
 
Most forum "regulars" know I dislike the electronic iggy setups and will choose points every time. But this '76 is already set up with the poxy "magic" system, so the logically easiest and least costly thing to do is get the Pertronix kit.

fireman said:
Ok, so how and what do I need to test to make sure my wiring is working properly?
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You have a test light, you stated the W/G coil terminal has voltage. Now you need to use a VOM and test for a less-than +12V (I don't recall what the exact +V should be, likely no less than +10V) at the DISCONNECTED plug going to the distributor, on the W/U wire. And you should have +12V at the W pin. If those are "hot" the reluctor and/or pick-up in the distributor are scrap. If there's NO voltage from that W/U pin, you've a bad resistor in that circuit. Follow the diagram posted in #48.


Try this link for a fairly local parts source: https://tsimportedautomotive.com/
 
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Ok... I Dohave power at the wwedding and w/u wires at the disconnected plug going to the distributor. So, you say this means that the "reluctor" and/or the "pick up" in the distributor are bad... What are these parts? I don't see them listed in the parts catalog. I assume the are part of the electrical components?

I am guessing that this means that I will have to bite the bullet and buy a new pertronix? Do I need to get the whole distributor (143-116) or just the ignitor(222-475)?
 
Call Moss and discuss it. IMO the #222-475 is the correct one BUT check with them first.
 
One of my distributors is a 43DE4, the other is a 45DE4. I called Moss, they transferred me to someone where I had to leave a message. Now just waiting for them to call back...
 
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