spark plugs condition
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,424
Likes: 127
From: Mequon WI
spark plugs condition
Hi Everyone,
I am thinking about replacing the spark plugs on my '78 L82. Not sure how long the current plugs have been in there but they are obviously not original. Car has 82K miles on it. I pulled two plugs out this evening and looking at them to me they seem to be in pretty good shape. Can someone with more experience comment? Would you continue to run on these plugs or change them?
I am thinking about replacing the spark plugs on my '78 L82. Not sure how long the current plugs have been in there but they are obviously not original. Car has 82K miles on it. I pulled two plugs out this evening and looking at them to me they seem to be in pretty good shape. Can someone with more experience comment? Would you continue to run on these plugs or change them?
Burning Brakes
Joined: Jan 2001
Posts: 1,219
Likes: 448
From: Loir Valley Sarthe, France
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Considering they cost only “pennies” and that you guys in the US can probably pick them up at a local “Pep Boys” or similar, I’d just replace them.
Now over here it’s not so easy, (or cheap!
) but I still usually change mine after about 6 or 7 thousand miles…
Now over here it’s not so easy, (or cheap!
) but I still usually change mine after about 6 or 7 thousand miles…
Advanced
Joined: Feb 2014
Posts: 97
Likes: 16
From: Green Bay Wi.
How much do plugs cost in France?
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Other than showing that the fuel mixture is a little on the 'rich' side, there is nothing wrong/worn on those plugs. Perfect fuel mixture would cause the dark/blackened areas to be more to the brown/tan color. But, the electrode and ground-lug appear to be undamaged and unworn.
You could clean those plugs up and reuse them; performance would be about the same as with new plugs of the same type/brand. You would actually have LESS risk from reusing plugs that you know have worked properly, than with purchasing new plugs which have NEVER been tested. Just cause it's 'new' doesn't mean it will always work or work properly.
You could clean those plugs up and reuse them; performance would be about the same as with new plugs of the same type/brand. You would actually have LESS risk from reusing plugs that you know have worked properly, than with purchasing new plugs which have NEVER been tested. Just cause it's 'new' doesn't mean it will always work or work properly.
Last edited by 7T1vette; Mar 27, 2015 at 12:41 PM.
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Burning Brakes
Joined: Jan 2001
Posts: 1,219
Likes: 448
From: Loir Valley Sarthe, France
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2024 C3 of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
Hi Apologies for a late reply - been having "fun" swapping U/Js! But, doing a quick conversion I'd say that one plug starts at about the equivalent of $3.80. Add to that shipping, as I couldn't buy plugs for a C3 at any local store - in fact there are probably only a handful of places in Franc, or my native England, that would stock them.
I'm fortunate in having friends over there in the US who we visit, so I usually "stock up" when I can. Last time I bought plugs they were $1.83 each!
I'm fortunate in having friends over there in the US who we visit, so I usually "stock up" when I can. Last time I bought plugs they were $1.83 each!
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
If you want to "read" the plugs this is the best I have found for that.
http://4secondsflat.com/Spark_plug_reading.html
As far as condition, they look good, no need to buy new.
http://4secondsflat.com/Spark_plug_reading.html
As far as condition, they look good, no need to buy new.
Thread Starter
Drifting
Joined: Apr 2004
Posts: 1,424
Likes: 127
From: Mequon WI
Ran the engine for a few minutes. The warehouse where I have it stoed is all closed up. After a few minutes the fumes were bad. My throat was sore and eyes running. A non mechanical test showing I need to do some tuning work. Then maybe carb work too. That. 4 seconds flat artcle is exceptional! Thanks for posting it REELAV8R.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Unless perfectly tuned (unlikely), a carbed car that has just started will run very rich, as it still has the choke engaged. If that car has only had short starts and/or runs at low throttle, the condition of those plugs is what one would expect to see. On longer runs, that plug color might lighten-up.
Still, no reason to throw them out...
Still, no reason to throw them out...