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Old 02-09-2018, 06:18 PM   #1
stevenfromtexas
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spark plug help!!!

Houston!!!....I'm scared we have a problem!!....

can you fine gentlemen help me troubleshoot my plugs

'67 250, petronix ignition, single barrel rochester, timed 10*, not road worthy yet

i've been tinkering and reading the forum until spring break; when i plan on painting. i will "tinker" and start my pickup just to run it and dream of cruising'. i started noticing the dreaded fuel smell in my oil. i've read the threads about this and plan on a new fuel pump. today i wanted to look at the plugs to see what they would tell me about how things are going so far.

here's where you guys punch me with some knowledge......

plug 1, 2 and 3 have lots of soot. 4 is starting to clear out and 5 and 6 look brand new

any thoughts for a rookie
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I wonder if my grand kids will say, "I would give anything to have my grand dads 2005 Chevrolet Z71"

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Old 02-09-2018, 06:19 PM   #2
stevenfromtexas
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Re: spark plug help!!!

#6

also.....gap set at .035
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'67 SWB, 250ci, 3OTT.......this is my first build......
I wonder if my grand kids will say, "I would give anything to have my grand dads 2005 Chevrolet Z71"

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Old 02-09-2018, 06:42 PM   #3
Grumpy old man
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Re: spark plug help!!!

Post a picture of your engine , Starting it and running for a few minutes won't allow it to get up to operating temp so playing with it for a few minutes will result with soot on your plugs, unburned fuel . rotate the plugs to see if there is any difference , what type choke is on it ? be glad it's not oil

one of the guys will chime in on the gap with the petronix
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Old 02-09-2018, 06:51 PM   #4
stevenfromtexas
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Re: spark plug help!!!

yes sir....

it does smoke for a little while (white) until it warms up. from what i've read that is fairly normal. i'll take some more pic after i change the oil and fuel pump.
it is a manual choke
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Old 02-09-2018, 07:32 PM   #5
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Re: spark plug help!!!

You need to change that oil cap out for a breather type cap.
Your pcv won’t work otherwise.
If you don’t there’ll be some oil leaks from blown gaskets.
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Old 02-09-2018, 07:58 PM   #6
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Re: spark plug help!!!

The gas in the oil could be bad rings. How old is the oil?
I'd do a leak down test before changing anything.

https://mobiloil.com/en/article/car-...-leakdown-test

And here is a guide for reading spark plugs yourself.

http://www.ngksparkplugs.com/about-n...d-a-spark-plug

Both of these responses are also great.

Quote:
rotate the plugs to see if there is any difference , what type choke is on it ?
Quote:
You need to change that oil cap out for a breather type cap.
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Old 02-09-2018, 09:13 PM   #7
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Re: spark plug help!!!

oil is actually a year old. i scribed the oil filter a year ago this month.

i've only started it occasionally just to hear it run while i was doing other things (wiring, brakes,......), 10 minutes at a time give or take...
thank you for the link about the plugs.
the first and second pic look like mine.
i was worried there were other things happening internal that would constitute a big set back...( machine shop ).....
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Old 02-09-2018, 09:18 PM   #8
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Re: spark plug help!!!

"leak down test" is this a compression test? if so, ok i'll try that.

my apologies........i went back and looked at your first link
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Old 02-09-2018, 10:36 PM   #9
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Re: spark plug help!!!

Quote:
Originally Posted by geezer#99 View Post
You need to change that oil cap out for a breather type cap.
Your pcv wonít work otherwise.
If you donít thereíll be some oil leaks from blown gaskets.
ok....thank you sir

i just looked up a breather style fill cap...thank you!! ill be getting one this weekend
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Old 02-10-2018, 06:40 AM   #10
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Re: spark plug help!!!

If it starts and idles remotely right on all 6, don't judge anything about your engine's state of tune until you can drive it. And you aren't doing it any favors by just idling it repeatedly like that. It likely won't hurt the old 6 but it won't help it any, either - maybe once every few months, but even at that rate run it until the thermostat opens. Once you get it road worthy change the oil, take it out for a jaunt with some highway running, then pay some attention to your plugs.
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Old 02-10-2018, 07:40 AM   #11
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Re: spark plug help!!!

I know you see a bunch of guys running those little air cleaners but I'd find one a little larger to help it breathe .
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Old 02-11-2018, 05:57 PM   #12
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Re: spark plug help!!!

Quote:
Originally Posted by Alex V. View Post
If it starts and idles remotely right on all 6, don't judge anything about your engine's state of tune until you can drive it. And you aren't doing it any favors by just idling it repeatedly like that. It likely won't hurt the old 6 but it won't help it any, either - maybe once every few months, but even at that rate run it until the thermostat opens. Once you get it road worthy change the oil, take it out for a jaunt with some highway running, then pay some attention to your plugs.
ok...thank you for the info. hopefully not too much longer before some driving.
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I wonder if my grand kids will say, "I would give anything to have my grand dads 2005 Chevrolet Z71"
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Old 02-11-2018, 05:59 PM   #13
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Re: spark plug help!!!

Quote:
Originally Posted by Grumpy old man View Post
I know you see a bunch of guys running those little air cleaners but I'd find one a little larger to help it breathe .

yes sir..... i'll look for a bigger one. thank you
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Old 02-11-2018, 07:27 PM   #14
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Re: spark plug help!!!

If it doesn't get run under a load, and experiences extended idling, the plugs can load up, especially with a manual choke. As was mentioned, get it on the road and under load, pushing wind. I bet it'll clean up. If you don't have water in the oil from condensation because the engine didn't get warmed up enough, that is good. Venting the crankcase via the PCV valve also removes those vapors. I've seen vehicles with foamy oil due to extended idling and not getting hot enough, especially near large bodies of water.

White when warming up is water vapor, most likely. Also, for the air cleaner, it looks like you need an oil filler cap that has a hose connection to go to a filtered air supply for the PCV valve. Look at some of the other 6 cylinder engines for examples.
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Old 02-11-2018, 08:09 PM   #15
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Re: spark plug help!!!

Quote:
Originally Posted by Steeveedee View Post
If it doesn't get run under a load, and experiences extended idling, the plugs can load up, especially with a manual choke. As was mentioned, get it on the road and under load, pushing wind. I bet it'll clean up. If you don't have water in the oil from condensation because the engine didn't get warmed up enough, that is good. Venting the crankcase via the PCV valve also removes those vapors. I've seen vehicles with foamy oil due to extended idling and not getting hot enough, especially near large bodies of water.

White when warming up is water vapor, most likely. Also, for the air cleaner, it looks like you need an oil filler cap that has a hose connection to go to a filtered air supply for the PCV valve. Look at some of the other 6 cylinder engines for examples.
thank you brother.....looks like i'll let this little guy sit a while then. i'm off several shifts in march so i plan on painting....
after that i'll only have a few things left before i can drive it...."fingers crossed" for june!!!!!
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Old 02-11-2018, 08:21 PM   #16
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Re: spark plug help!!!

Quote:
Originally Posted by stevenfromtexas View Post
ok...thank you for the info. hopefully not too much longer before some driving.
Glad to help, if I did.

Hope you get her road worthy soon! That engine looks purdy. What kind of plugs are those?
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Old 02-11-2018, 08:25 PM   #17
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Re: spark plug help!!!

absolutely!!
thank you for the compliment....
it's been a lot of fun and have learned a ton from you guys and trial and error

....standby and i'll check...."plugs"
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I wonder if my grand kids will say, "I would give anything to have my grand dads 2005 Chevrolet Z71"
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Old 02-11-2018, 08:36 PM   #18
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Re: spark plug help!!!

Autolite 65

...hate to poke a sleeping bear... like i said, i'm a rookie and "just bought some random plugs"..... once i get this guy rollin' i will switch the plugs around per grumpy's advise and see how things go


fixing to open the pivotal can of worms.......
any advise on a certain plug you guys use?
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Old 02-11-2018, 09:48 PM   #19
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Re: spark plug help!!!

Quote:
Originally Posted by stevenfromtexas View Post
Autolite 65

...hate to poke a sleeping bear... like i said, i'm a rookie and "just bought some random plugs"..... once i get this guy rollin' i will switch the plugs around per grumpy's advise and see how things go


fixing to open the pivotal can of worms.......
any advise on a certain plug you guys use?
Plugs are like women. Every guy has a different idea of what is ideal. If those F-F-F-Ford plugs are in the interchange for what the stock AC Delco plug is, go ahead and run 'em. You should, however, get the carbon off them before you put 'em back in.
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Old 02-11-2018, 10:47 PM   #20
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Re: spark plug help!!!

There's certainly variety in plug choices. The only input I'll offer is that I've never seen a set of Autolite plugs that wasn't visibly eroded - even iridiums in calm modern car/van V6's, and they couldn't have all been 120K+ miles old. Which also coincides with the fact that they're usually one of the cheapest options in a given application. And that your leisurely six won't have any problem with good ol' copper plugs.
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Old 02-11-2018, 11:10 PM   #21
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Re: spark plug help!!!

Quote:
Originally Posted by Steeveedee View Post
Plugs are like women. Every guy has a different idea of what is ideal. If those F-F-F-Ford plugs are in the interchange for what the stock AC Delco plug is, go ahead and run 'em. You should, however, get the carbon off them before you put 'em back in.
yes sir, will do.
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Old 02-11-2018, 11:15 PM   #22
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Re: spark plug help!!!

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Which also coincides with the fact that they're usually one of the cheapest options in a given application. And that your leisurely six won't have any problem with good ol' copper plugs.
yes sir....at the time, "cheap" was in order.

"copper plugs" any suggestions?????
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Old 02-11-2018, 11:50 PM   #23
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Re: spark plug help!!!

With the PerTronix ignition you should be gapping your plugs at .045 just like HEI, or any other electronic ignition. [.035 is for points only.]
Ignitor I or II?
I use Densos now that ACDelco went South of the Border. Their QC fell off the face of the known universe.

Also what viscosity oil are you running? For the Southwest [I'm in Tucson], I recommend straight 30 SAE. I run Valvoline Racing [VR1] SAE 30 in my '68 292 L6. Engines of this vintage were designed to be run on straight weight oil.
On my last 292 (that went 250,000 miles) I started out with 30 weight, then 40 weight after about 150,000, and finally I was blowing blue smoke rings of pure 50 weight coming up on 250,000, when I decided to pull it out and rebuild.
What do you estimate the elapsed mileage at on your 250 L6? [More miles, the thicker the oil.]
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Old 02-12-2018, 12:04 AM   #24
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Re: spark plug help!!!

Quote:
Originally Posted by '68OrangeSunshine View Post
With the PerTronix ignition you should be gapping your plugs at .045 just like HEI, or any other electronic ignition. [.035 is for points only.]
Ignitor I or II?
I use Densos now that ACDelco went South of the Border. QC fell off the face of the known universe.
ignitor I

ok, thank you for the info!! i'll save this info for when i get "driving".

thank you very much!!
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Old 02-12-2018, 12:05 AM   #25
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Re: spark plug help!!!

NGK is regarded by many as one of the best. I've put plenty of their platinum and iridium plugs in newer engines with fine results, but both my old Chevy V8's have AcDelco's in them. Copper is the common term for the traditional plugs with the large, square center electrode. You could research or contact the ignition system company and ask their recommendation on plug type and gap because as '68orange said, the stock gap specs may no longer be ideal for your setup.
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