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Discussion Starter · #1 ·
Testing magnetic trigger.

How do you test a new distributor for an 84 jeep Cj7 258ci. if the distributor is sending out a signal? Can a new rebuilt distributor from Kragen be defective?

I have just installed a Howell TBI and using a Crane HI-6 CD ignition. My problem is the engine will not start. The red trouble light on the Crane ignition unit is not showing the strong 'FLASH' as required indicating that it is receiving the signal. I have eliminated the stock ford ignition module by wiring the new rebuilt distributor orange and purple wires directly to the Crane Magnetic trigger cables.

I should of kept the old distributor as Junk Yard Genius tolled me too. Opps!

Thank you
 

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Hook a voltmeter on AC across the two colored leads (not black) and spin the distributor. I don't remember what the voltage was since it has been several months since I did it but if it shows nothing, you have a problem.
 

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If you look in a manual you will see a check using an ohmmeter. There should be infinite reistence between Black and the purple or orenge. Purple to Orenge should be 600 to 800 ohms if my memory is correct, You should check.

This has nothing to do with your current problem but an 84 distributor is setup to work with a computer. It uses different springs and has a limit on the mechanical advance. If you are not useing the computer you will not get full advance and will not get the power or milage you should.
 

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It's best to use an analog type meter - needle/pointer type, as the digigtal meters only "sample" and it's hard to get them to capture the pulses.

Use the lowest voltsge scale you have - 2.5 volts or? You can use either the AC or DC scale - even the Ohms scale will work.
Spin the distributor - crank or by hand it it's out. You'll see the needle wildly swing.

Try it with the connector connected to the module, and without. Sometimes the input of the module goes bad, shorting your signal.

Make sure it even gets to the module too.
 

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Discussion Starter · #5 ·
Thanks all for your fast response. I will test it tonight and see! I do have a analog volt meter that will use. I can not imagine if it's anything else to cause the trouble light to not to register the signal correctly.

It sucks, especially when all the work you put into it for over a year and a half of a minor overhaul. All you wont it to do is START!
 

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Discussion Starter · #7 ·
Yes it is california smog approved. Kit come with the E.O. ID number required by California. That’s why I bought it so reliability and smog checking will be less of a issue on a 22 year old vehicle

Thanks
 

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Discussion Starter · #8 ·
Well, still working on it. I did not check the voltage yet but I did check with a timing light that I was getting a spark. So, I would assume that the distributor is producing the spark signal and the HI-6 CD Ignition is correctly reading the trigger signal.

Now on to the next testing phase of the problem why I cant get the Howell TBI to fire at startup, but that will have to be a different thread.
 

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Polarity from the mag trigger to the module is more important than testing the voltage produced.
The Motorcraft distributor Orange wire is positive.
The Motorcraft distributor Violet wire is negative.
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Mag trigger test in the distributor.
Use a Ohm meter and test the orange and violet wires for resistance.
400 to 800 Ohms is what you are looking for.
Do a test from each wire to the distributor housing, the reading should be 0 (Zero).
 

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Discussion Starter · #10 ·
Thanks for the help, all tested as stated above on the rebuilt distributor. However, the problem turned out to be that the engine was not cranking fast enough at start-up to create a trigger signal. In fact, by trying so many times to start it, it became noticely harder to turn over. Now you can't even turn it by hand with out a large crescent wrench to the harmonic balancer bolt! I think the engine is toast. It does not surprise me since it probably has 300,000 plus miles on it and it the only thing that has not been rebuilt yet.

Thanks again.
 

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Compression will go down as oil on the cylinder walls is scraped off.

Squirt some oil (engine oil, 3M oil, NOT penetrating oil) in the cylinders and see if your compression comes back.

Once the crank starts slinging some oil, the cylinder walls get a pretty good dose and are 'Self Lubricating' from that point forward.

Also when you turn by hand, the oil pump will loose prime and make the engine easier to turn over.
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You can get a stronger trigger signal by moving the mag trigger closer to the reluctor, or doubling up on magnets at the trigger's tail.
This would be a good time to go to Ford and buy a Factory replacement.
If push comes to shove, I can build you a dual trigger unit that will use two mag trigger units in the same distributor just to make SURE the module gets the signal!
 
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