67 427 390 AC Spark Plug Changing Procedure

[Jimmy G.]

For those of you who know me, you know I can do about anything on a C-1, C-2 and early C-3 cars. However, it has been about 12 years since I changed the plugs on my 67 427 AC car. As you could probably guess, I have 6 changed already. Looking for advise on changing the 2 under the compressor. It seems as last time I tried through the inner fender - no good. I tried reaching under the compressor from the rear - Arms too big. If I remember I took the compressor loose from the mounting brackets and moved it up as far as I could then changed them. Anyone had any recent experience in doing this job as I am open to suggestions. Sometimes I hate AC cars!!! Thanks

[Mark E.]

Re: 67 427 390 AC Spark Plug Changing Procedure

I've done this two ways for my '70 454 AC car-

- Remove RF wheel and work through the inner fender opening. Not easy but doable. Removing the AC belt and sliding the compressor in its adjustment slot may help while doing this.

- Unfasten compressor from its brackets and move it aside a bit.

Less disassembly with #1 but easier access with #2. Choose your poison.

C2 may be different but hope this helps.

If it makes you feel better, changing plugs in a C4 LT1 is a bigger PITA.

[Leif A.]

Re: 67 427 390 AC Spark Plug Changing Procedure

For those of you who know me, you know I can do about anything on a C-1, C-2 and early C-3 cars. However, it has been about 12 years since I changed the plugs on my 67 427 AC car. As you could probably guess, I have 6 changed already. Looking for advise on changing the 2 under the compressor. It seems as last time I tried through the inner fender - no good. I tried reaching under the compressor from the rear - Arms too big. If I remember I took the compressor loose from the mounting brackets and moved it up as far as I could then changed them. Anyone had any recent experience in doing this job as I am open to suggestions. Sometimes I hate AC cars!!! Thanks

3/8" ratchet, 2" extension, 3/8" swivel against the spark plug socket. You will get scratched up but, definitely, doable. Helpful hint for install: get a 4" piece of 3/8" ID thin wall rubber hose, push it down over the spark plug insulator just enough to hold the spark plug. Then, holding the hose, insert the spark plug into it's hole and use the rubber hose to screwing it in. Really tough to get your fingers in there with a spark plug...the additional length of the rubber hose makes it quite a bit easier.

[Peter M.]

Re: 67 427 390 AC Spark Plug Changing Procedure

Jimmy,
I remove the front wheel to change #2 plug, #4 I am able to replace from above with great difficulty. In addition to Leif's list of tools I have a short Snap on wobble extension.
I find #8 plug the worst, my car has K19.
The bleeding usually stops fairly quickly.
Kind regards

[David M.]

https://www.google.com/search?q=spark+plug+socket+with+a+hex+head&sca_esv=584176901&sxsrf=AM9HkKliReunFjz1mD6fWlaxZtbLuDE5mw%3A1700535353674&ei=ORxcZYfmKNO15NoPqO2c4Aw&ved=0ahUKEwjH5rvti9SCAxXTGlkFHag2B8wQ4dUDCBA&uact=5&oq=spark+plug+socket+with+a+hex+head&gs_lp=Egxnd3Mtd2l6LXNlcnAaAhgCIiFzcGFyayBwbHVnIHNvY2tldCB3aXRoIGEgaGV4IGhlYWQyBRAhGKABMgUQIRirAjIFECEYqwIyBRAhGKsCMggQIRgWGB4YHUi5gAFQAFjFdnABeAGQAQCYAc0CoAHcH6oBCDkuMjQuMC4xuAEDyAEA-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_CAgsQABiABBiKBRiGA-IDBBgAIEHiAwUSATEgQIgGAboGBggBEAEYFA&sclient=gws-wiz-serp

And a hex with square drive:

https://www.ebay.com/itm/325488462889?chn=ps&norover=1&mkevt=1&mkrid=711-117182-37290-0&mkcid=2&mkscid=101&itemid=325488462889&targetid=1645685073808&device=c&mktype=pla&googleloc=9005677&poi=&campaignid=20133407470&mkgroupid=147476396765&rlsatarget=pla-1645685073808&abcId=9312979&merchantid=113670333&gclid=Cj0KCQiApOyqBhDlARIsAGfnyMrdIqBcRBm3muHfM-ucr5n4JO9NwUoaNRWMc7LphHFgy1TIN59Bo5oaAg8FEALw_wcB