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Discussion Starter #1
Here's what changed:

1. New HEI coil-in-cap distributor
2. New HEI wires - all correct and "snapped" in
3. New r44t spark plugs gapped to .45

I found out it was the #1 cylinder because the header pipe to it did not even get hot to the touch, every other one was blistering hot. Pulled hte plug and it looked brand new, covered in oil though. I compared it to the #3 cylinder plug to varify that it hadn't even fired.

What could it be?
 

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Discussion Starter #3
what do you mean by that, i think its the timing, but other suggestions are more than welcome
 

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Did it run on all 8 before the changed parts?
If it did, possibly a bad plug or wire. Covered with oil doesn't sound good. If the other 7 are firing, I don't think timing would cause 1 not to fire at all. Good luck
 

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Discussion Starter #7
hmm i was planning on swapping heads in a month or two anyway, so any valve issues should soon be resolved. Playing with the timing a bit seemed to get it almost completely gone, we are going to get a new timing light and try to nail it and it should be gone.

How do you know what the timing "should" be set at? Must we guess and check? Is there atleast limits that we should be sure to stay between?
 

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Originally posted by Chirp08:
hmm i was planning on swapping heads in a month or two anyway, so any valve issues should soon be resolved. Playing with the timing a bit seemed to get it almost completely gone, we are going to get a new timing light and try to nail it and it should be gone.

How do you know what the timing "should" be set at? Must we guess and check? Is there atleast limits that we should be sure to stay between?
Changing the timing may help the misfire but it's not the cause. As was said timing affects all 8 cyl, not just one. You have another problem and changing when the plug fires can stop the misfire but you're probably running on 7 cyl not 8.
 

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Replace #1 plug with a new one and try again. If the plug is coated with oil, it will NOT fire. Also, hook up a timing light to the #1 plug wire to verify that the plug is firing. If there is NO indication from the timing light, change the plug wire. If it is, set timing to around 4 degrees ( a good starting point). If it's STILL missing, a compression test is in order to determine the problem.
 

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Discussion Starter #10
alrighty, will do what you said malibujerry, yeah the timing will change the rpm its idling at too, which hides the misfire to the ear, but its still there. I dont see how this could happen overnight though, it wasn't there when the points distributor was in :/

I know for a fact that the wire is firing, i did the old pull the wire off and hold it close for the spark test. So i guess that means the plug just isn't firing, if the plug *is* firing than it means something else is up, so i guess i can try putting one of my old working plugs in there to verify if its the plug or not.
 

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What did the previous #1 plug look like? Did the engine smoke or burn oil? Oil on a plug is not a good sign.

Also: (Quick diagnostics)
You could also pull the plug from #1, flush it with some gum cutter or choke cleaner and swap it with another that's easy to get to. If the trouble moves, it's a bad plug (they've been know to be bad out of the box). However, if #1 still doesn't fire, swap the wire with another. If the trouble moves, then......

If #1 still doesn't fire, check the cap for a bad contact or crack. If that's not it, you got serious problems. COmpression check time.
 

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Discussion Starter #12
god pray i dont have serious problems, i cant afford to tear down the block, not to mention this is my daily driver so i dont even have time to do it :(

Is there a chance that the oil is coming from a problem in the heads and not the bottom end? If so that would be o.k. because i was planning on doing hte heads anyway, but this problem may decide waht i do next.
 

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Originally posted by Herb:
What did the previous #1 plug look like? Did the engine smoke or burn oil? Oil on a plug is not a good sign.

Also: (Quick diagnostics)
You could also pull the plug from #1, flush it with some gum cutter or choke cleaner and swap it with another that's easy to get to. If the trouble moves, it's a bad plug (they've been know to be bad out of the box). However, if #1 still doesn't fire, swap the wire with another. If the trouble moves, then......

If #1 still doesn't fire, check the cap for a bad contact or crack. If that's not it, you got serious problems. COmpression check time.
Good advice Herb, its real easy ona small block to swap cyl 1 with cyl 3 the wires are about the same length. At least then you'll know if its spark related or not.
 

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Chirp08,
Don't borrow trouble. Do the swaps I suggested and go from there. A compresion test and leak down test will be next and helpful. There are a lot of guys on here that can help you diagnose your problem. I'd want to know the results of these tests before I put new heads on my engine anyway.
 

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Based on previous replies the wires, cap, etc. are good. Spark jumping to plug test. Herb is right on the bad plug thing, bad out of the box and also easy to crack the the ceramic insulation when installing. Quickest thing is replace or swap with a differnt one and go from there. Compression, leak down test as suggested.
Or check your grounds, right Herb? Private joke, disregard Chirp.
 

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Discussion Starter #17
right, well it turns out that we are 99% sure its not he rings, the problem didn't happen until we added oil to the new breather, located above cylinder #1, which would explain why there is oil on the plug, its coming from above probably. TOmmorrow i need to check the plugs, is there a more efficient way other than just moving wires around?

If the plugs wires check out to be fine we are going to put hte points back in there to see if the problem goes away.

Hopefully the heads are fine because we are highly considering a 383 shortblock :D
 

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Just swapping the wire IS the simple method, takes 5 mins and no tools. That's a hell of a lot easier than swapping distributors!

I'd do that before I'd dump the HEI. It is far superior to the point system and worth using. If it was the dist., you would be seeing the problem with more than one plug. I suspect it's a bad wire, plug or cap in that order. Hence the reason for the process I gave you.

When you said there was oil on the plug, we thought you meant the electrode, not the outter shell. I recommed you remove the plug, wash it off with a solvent and swap it with the adjacent cylinder. Again, that IS the easy way to validate the plug's integrity.
 
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