Engine not creating a spark

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Just purchased a 72 FJ40 and it was converted to a Chevy 305 by PO. I have a someone with a ton of experience working on Cruisers (60+) and we are both at a loss on what is going wrong. Replaced the distributor cap and even hard wired directly to the battery with no luck of creating even the faintest spark. Is there something we are missing?
 
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Do you have an engine ground on the truck?
Hey Ceylon, we do have the engine grounded on the truck. We have created a complete circuit, but there is still no spark. The guy who is helping me out has extensive knowledge of rebuilds(both on the inline 6 and with a conversion), but even he can't figure out what's going on.
 

ceylonfj40nut

Waiting for Barn Time
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Some engine pics would help.

Disconnect -ve terminal and connect a test light between terminal and battery post. Light up? If not there is a disconnect. Check voltage between -ve terminal and -ve battery post. Report back. How do you know if coil is good?
 
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What's been tested? The coil is pretty simple to test in isolation by interrupting the ground to it while keyed on / 12v being supplied...does the coil test out as good? (That assumes it's getting its switched 12v+ of course, which is probably test 0).

From there, it would go to the distributor to make sure the points are doing what they need to do (assuming points).
 
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Thanks for all the responses. After replacing the HEI cap and ignition coil, we are still not getting any spark. For another few dollars, we’re going to just replace the entire distributor.
 
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Check the condenser on the distributor. One of my father's land cruisers, which also has a Chevy engine, was having a similar issue. I think there was spark, but extremely weak and the engine would not crank....got the condenser replaced and it worked. perhaps you already got the new distributor, but in case you still have it laying around as a spare.
 
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Make sure the centre dizzy cap ht lead to coil is ok. If it has points and they are new , make sure the little plastic protection cap that are sometimes on new points contacts is removed. If it has a hei module, the 2 pickup wires have to be on their correct module terminals. They won't work if reversed.
Some chev rotors have a sprung steel tab that sticks up in the centre. They can get squashed flat and not touch the graphite button in the dizzy cap.
 
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Make sure the centre dizzy cap ht lead to coil is ok. If it has points and they are new , make sure the little plastic protection cap that are sometimes on new points contacts is removed. If it has a hei module, the 2 pickup wires have to be on their correct module terminals. They won't work if reversed.
Some chev rotors have a sprung steel tab that sticks up in the centre. They can get squashed flat and not touch the graphite button in the dizzy cap.
Thanks pithicus... I ended up replacing the whole distributor. Once I put a new one in, it fired right up and we were able to time it correctly.
 

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