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Old 02-01-2012, 06:43 PM   #1
xs-style
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plug issue. help?

Well guys I have yet another question in my trucks progress. I changed up plugs and wires. I took extra time and did them one at a time and tied them up nicely. Nice new plugs and wires all tied off look so nice... untill you realize the truck wont fire up anymore. Then the time spent just ticks ya off.

Ive checked connections and firing order. So those are off the list. The distributor is recent, so I wouldnt think that would be a problem. Timing was checked when the new dizzy went in, so that should be fine. The only thing I can think of that changed was plug gap. Now when I took the old plugs out, they were black and some looked damp black. That makes me think to much gas. Despite that, the truck still fired with just one pat of the gas, even if it had sat for a week. I checked the gaps on the old plugs, and it was gapped at between a .30 and .35. But from reading the forum, and per the specifications on the Advance computers... a HEI distributor should have plugs gapped at a .45. So I gapped them to .45. Should I back down that gap a bit? On one hand we have specs from the advance computers, damp black plugs and this forum sayin .45 is the way to go... but it actually fired up and ran at .35. Ideas?
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1978 Scottsdale - celebrating 10 years of teaching me profanity
1990 Silverado - bought in Nov. 2016 and it's already catching up - Sold
1987 k5 blazer - sold... :\ seed money for the 81
1981 k20 4x4 - 5.3 swap in progress

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Old 02-01-2012, 09:41 PM   #2
D-Day
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Re: plug issue. help?

Perhaps times for new ignition coil?

And as much as I hate to say it, because I've been broke down while broke, but buy the good quality parts...had bad luck buying the cheapies and ultimately threw in a MSD Streetfire and it roared up on the first turn. I hate ignition problems...well, any kind of problems really. But electrical the most, I think.
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Old 02-02-2012, 01:34 PM   #3
motornut
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Re: plug issue. help?

check power at the coil (beige wire)
make sure tach side isn't grounded
think i've seen the black ground in the coil top in such a way was the power was'nt grounded....the bar under the coil
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Old 02-02-2012, 04:45 PM   #4
xs-style
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Re: plug issue. help?

Well guys I went back and re gapped the plugs to .35. It fires on the first pat of the gas and idles normally now. I dont get it though. I read on here that all dizzys with the coil on top are considered HEI and should have a .45. I dont guess it really matters now that the problem seems resolved, but I still would like to know what happened.
__________________
1978 Scottsdale - celebrating 10 years of teaching me profanity
1990 Silverado - bought in Nov. 2016 and it's already catching up - Sold
1987 k5 blazer - sold... :\ seed money for the 81
1981 k20 4x4 - 5.3 swap in progress

Events attended:
Spring GOG 2011
Dale JR car show Summer 2012
Gathering at Tommys pickup parts
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