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Ignition Mystery! Please Help

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darnelld View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote darnelld Quote  Post ReplyReply Direct Link To This Post Topic: Ignition Mystery! Please Help
    Posted: Jun/20/2022 at 5:27am
Hey guys

Here is the short story. Car ran really well, had a nice Cruz last weekend. Went to check the torque on the intake bolts and took of the distributor cap for access. Dumb me tried to crank the car without the cap on, now it wont start. I removed the first plug and put my thumb over it to get it close to TDC and then advanced it a little on the crank. The car will wont start! I am a bit of a loss. Clearly I forgot to do something, but not sure what. Any and all advice is welcome to get my car started.

Thanks beforehand

Dean
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Buzzman72 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2022 at 5:34am
Just removing and reinstalling the distributor cap shouldn't change the timing.

My guess is there's a carbon "button" inside the cap that contacts the rotor, and when you removed and replaced the cap. it fell out. Can't say for sure because I don't know which distributor you have. Some have the carbon button, while some still have the brass center terminal at the rotor contact.

But I'd bet something of that nature occurred.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote 6PakBee Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2022 at 7:35am
Troubleshooting 101 on older vehicles, check for fuel, fire, and squeeze.

1)  Look down carb, pump throttle, do you see discharge from accelerator pump nozzles?  If so you have fuel.

2)  Take off one plug wire, attach to used plug, lay on block, crank engine, do you see spark?  If so you have ignition.

3)  Do a compression check on one cylinder, do you have a reasonable reading (> 100 psig)?  If so the engine is probably mechanically sound.

If you have done all this and it still won't fire, it's probably something simple like it's flooded or something more exotic has happened.  But this is how you start to narrow down the problem.
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mixed up View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote mixed up Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2022 at 11:24pm
I would look at the center of the cap see if that button is there first then look for spark at the coil
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Post Options Post Options   Thanks (0) Thanks(0)   Quote rgsauger Quote  Post ReplyReply Direct Link To This Post Posted: Jun/20/2022 at 11:52pm
Losing the little spring loaded button sure seems plausible 
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darnelld View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote darnelld Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2022 at 6:51am
Hey guys

So the spark is there. I actually replaced the cap, then pulled the plug and grounded the plug threads to chassis. Sure enough spark. THe engine just doesnt try and crank. I pulled the carb out and am cleaning it but this is the last thing I can think of. Even if the engine didnt have compression you would hear it try and turn over, right? All I hear is the starter trying to turn it over.

Thoughts?

Dean
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mopar_guy Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2022 at 11:13am
What color is the spark? Orange is a cold spark and won't run on it so you need a blue spark.

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darnelld View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote darnelld Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2022 at 1:22pm
It looked blue :/ 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote bigbad69 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2022 at 3:02pm
Originally posted by darnelld darnelld wrote:

THe engine just doesnt try and crank.
So you're saying the engine won't crank, yet you were able to verify spark????

Please confirm the engine does or doesn't crank. It would really help with the remote diagnosis.
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darnelld View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote darnelld Quote  Post ReplyReply Direct Link To This Post Posted: Jun/27/2022 at 3:13pm
Originally posted by bigbad69 bigbad69 wrote:

Originally posted by darnelld darnelld wrote:

THe engine just doesnt try and crank.
So you're saying the engine won't crank, yet you were able to verify spark????

Please confirm the engine does or doesn't crank. It would really help with the remote diagnosis.

Oh sorry for the confusion.

I removed the plug 1 and grounded the threads to the neg battery terminal and then had someone crank the engine. At that point there was a blue spark.

When the plug is in the head I turn the ignition over and it will not crank. I just hear the starter. The mechanical fan turns ~one cycle (I can see it from between the hood from the drivers seat) but that is it.

Let me know if you would like any other details

Thanks again

Dean
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