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Re: crane xr 700 optic ignition system question

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ferrmgt

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Re: crane xr 700 optic ignition system question

Hi, love the forum

question, my 1977 mgb had a crane xr 700 optical ignition system installed years ago. it has worked perfectly until... a couple of months ago. finally have time to work on the car and am getting no where. I have no spark at the plugs, no spark at the coil, and no led blinks. I ordered another xr700 ignition and installe today. same problems. Anyone have any ideas? thanks for the help.
 
Re: crane xr 700 optic ignition system question

Not Sure, how would I check that? I will look into it...
 
Re: crane xr 700 optic ignition system question

If you have 12 volts, did you replace the pickup in the distributor when you replaced the ignition. Mine quit one day due to water dripping from the heater valve on to the distributor which I tried drying out the cap first then after getting it towed home found dampness in the infrared pickup and by drying that out and cleaning it, got it working again. Also you might make sure you have a good ground.
Bob
 
Re: crane xr 700 optic ignition system question

Bob, just thought I would say that top the same color as the car looks great. Are they supose to be the same color on Bs?
 
Re: crane xr 700 optic ignition system question

bob,
thanks for the help, I did change the pickup (LED light source I think you mean) and to no avail. I think I will change the distributer cap and rotor just for good measure, since I dont know how old they are. I am interested in checking the power source to the ignition module but dont know how, do you?
thanks for the help.

michael
 
Re: crane xr 700 optic ignition system question

No, Jack, the original color for mine was black. The top was given to me by a friend of my son after I took him in when his mother kicked him out of the house. He brought it to me from up north strapped to the trunk of his american car. I painted it at the same time I painted my car in the same color which wasn't an MG color.It is a chevy color crimson red from 1996.
Bob
 
Re: crane xr 700 optic ignition system question

Michael, one of the wires going to it should have 12 volts on it. I will look at mine tomorrow and see which one does. Usually red but I will check.
Bob
 
Re: crane xr 700 optic ignition system question

Well I must say that I like that red and even more think the top looks right painted the same color as the car. Suspose they did not paint tops so one would fit all, another bit of cost saving at the works.
 
Re: crane xr 700 optic ignition system question

Well, Jack, most people didn't buy the hard top when they bought the car. It was offered as an accessory so that would be the reason they painted them a color to match all colors. I agree that it loks better painted the same color as the car just like I think the rubber bumpers look better painted the same as the car but with the many different opinions we see just on this forum, immagine trying to satisfy the world.

Michael, I checked my XR700 and the red and yellow wires go to the coil. The red is on the + terminal and has close to 12 volts on it with the ignition switch on and the motor not running. The yellow is the ouput from the ignition and with the car running and the voltmeter on AC I read about 1.6 volts AC. This is most likely a square wave so the meter can only average it. A scope would show the real story. I only get 11 volts at the red lead but I checked the diagram and it goes through the tach before it gets to the coil so is probably dropped slightly through there.
Bob
 
Re: crane xr 700 optic ignition system question

bob,

thanks, I will try to do the same this evening. Crane says by the way that a true 12 volts is needed to fire the led pickup. interesting, you have 11v and the guy on the phone from crane was strong in saying the led wont fire with out 12v? I will keep you posted.
thanks again.

michael
 
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