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Old 02-15-2006, 03:09 PM
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joe350s10 joe350s10 is offline
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Ok, finally found the true problem!

After various tests I decided to take the entire dist. to the college and put it on our machine.

before doing so I completely disassembled it and thoroughly tested everyhting.

Coil tested fine.

Module tested fine.

Pickup coil tested fine.

magnets are still good and strong.

Dist cap has no apparent craks or carbon tracking.

treassembled the dist and hooked it to the dist testing machine...

No spark.

Pulled the cap off and jumpered to it. coil fired fine.

With the cap off, pulled off the rotor and tested it. rotor tested fine...until we pressed the tang down to simlulate the cap being on...


Apparently the rotor had developed a small crack/hole beneath the tang that connects it to the dist cap/coil. when fully depressed the spark was jumping through that small hole and going straight to ground through one of the mounting bolts. It had also been the culprit that killed the module and original coil. the apparent defect could not be detected with the naked eye...

So, after all that testing and retesting...buying new parts...etc...

It all boiled down to a bad rotor. The one part I thought was OK.

But, at least I know that everyhting else is functional...and I learned not to overlook the simple things.

Thanks once again for all the replies.

I'm going to buy a new cap and rotor tonight and get my beloved truck up and running again.

Just in time to race a friend from the college in the 73 vette I just fixed for him
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