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Spark plug replacement

Old Mar 1, 2023 | 03:25 PM
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Default Spark plug replacement

Until I can get my hands on the floor plans and a welder, I'll be working on some other smaller things like replacing the spark plugs and getting a few manuals.
Speaking of spark plugs, does anyone have any tips on how to get to them in the first place? I've taken the wheels off (which was a headache all together due to rusted lugs) and now it seems like the fender liner is in the way.
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Old Mar 1, 2023 | 03:51 PM
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No easy way. Take your time and wear mech. gloves. I've always replaced mine from above.
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Old Mar 1, 2023 | 06:00 PM
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Put the front tires back on and drive it up on ramps. All Vette owners should have ramps. So much safer & faster than floor jacks / stands.

From underneath, things will look a little easier on several of the cylinders. If you have headers, forget the old school way with ratchets and extensions.
However, your sparkplug socket should be hexagonal on the end. This allows a box-end wrench to be used on some stubborn cylinders, or a open-end wrench on others to grab the socket.
All new plugs should get a dab of anti-seize. Snug-em down. Snug-em again.
Enjoy!
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Old Mar 1, 2023 | 06:53 PM
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I have always been able to get all eight out from the top. I have a 1968 C3 with a 427 and long tube headers and there is plenty of room left over. The only real challenge can be the #7 spark plug because of the power brake booster. On our 1988 C4 it is a whole different matter and it becomes easier to remove the wheel well covers with the hood open. It takes about 20 minutes on my C3 and 2 hours on the C4 (if you are lucky).

If you have headers they make special spark plug sockets that make it easier to remove the hard to reach spark plugs. I have a set in my tool box but have not found them necessary on my C3 or C4. Having a proper size box wrench is always handy, I prefer the ratcheting type to make life easier. If they are stuck or really hard top remove be sure to use penetrating on oil them several times before you break the spark plug by using too much force.

The suggestion of using a dab of Anti-Seize is a very GOOD/ GREAT idea! Just a dab will do you so don't apply too much. Lately I have read several situations where people have used Die-electric grease on their plugs, not a good idea. Die-Electric is to be used VERY Sparingly inside the cap that goes over the end of the plug. Die-Electric grease impedes the flow of electricity so use it accordingly. As far as the spark plug anti-seize, they make various options. You really don't want thick Graphite based anti-seize on the base of the spark plug. Most auto parts stores will have a thinner mixture more suited to use on spark plugs. I bought a small bottle of Champion brand spark plug anti-seize and the ~4ox bottle will probably last me a lifetime.

If your engine is using Aluminum cylinder heads and your spark plugs are made of steel it is VERY important to use a good anti-seize. When you don't it is possible to get Galling to occur on the threads which makes the plugs even harder to remove. If they don't come out easily I will try while the engine is almost cool and if necessary I will apply some good penetrating oil at the base of the spark plug.

I see that you are a fairly new Forum member, WELCOME to the Corvette Forum! You came to the best place to get good answers to your Corvette issues. When you have a moment please fill out the "Profile" section and give us some information regarding your Corvette. There are so many variation between the 1968 like mine and the 1982 Corvettes. When you enter the information it makes it easier for us to know what Corvette you are talking about.
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Old Mar 2, 2023 | 12:09 PM
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I've owned mine since new and I've always done all 8 from above.

The fun part is getting the shielding back on...
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Old Mar 2, 2023 | 02:03 PM
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Spark Plug socket and a 3/4 wrench.......break them loose and spin out with your fingers.....I don't even use a ratchet.

Jebby
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