Spark plug time
 

Now that the old beast's engine is all buttoned up tight again, I thought I'd treat her to a set of new plugs.

Looking around for the OEM Champion RC9YCC's, I see they are not so easy to source anymore (but I can get them in a pinch) - I see Rock auto has RC9YC4's - was wondering what the difference was between these two types?

I am a fan of the old Champion RC9YCC's, having had a smooth running motor all the time I've owned her. Don't want hotter or any fancy schmancy plugs as I don't like holes in my pistons.

Any recommends or advice on the two types of Champions?

TIA

Larry

What is wrong with the Champion #344? (RC9YC)

I don't know what the additional C at the end is for but I never cared.

I just buy Champion #344 at the local auto parts store.

bob

Yeah Bob, not sure what those C and 4 suffixes are all about, one guy said it was the out-of-the-box gap size? Not sure, but I'd like to know ..

The RC9YC4 is listed as a #430 ..Rockauto has the #344's too ..probably my auto parts place in town does too - I'll call

Larry

Well I chickened out, ordered the OEM Champion RC9YCC's from a guy in the UK - only 2 bucks shipping and I'm in no hurry, I'll get em next month ...:icon_neutral:

The reason I stuck with the RC9YCC's is that the car is still running on the original plugs that were in her when I bought her back in 2012 :icon_redface: (yes I've checked them over the years - no fouling and correctly gapped - amazing!)

Larry

My recollection is that the two Cs stood for "Double Copper." Apparently, at some point Champion "improved" the electrode design and discontinued the double copper nomenclature. As far as I was aware, the RC9YCC has been unavailable for many years. Ditto the RC12YCC, a slightly hotter plug that Jaguar retroactively specified in X300s that were originally equipped with RC9YCCs but which suffered from idle or driveability issues.

As far as I know, the RC9YC and RC12YC are identical to their predecessors in resistance and temperature range. Since the double copper versions became no longer available, I've used the single-C versions in every AJ6 and AJ16 I've serviced with the only plug-related problems being that the electrodes do eventually wear out, and if the cam cover gaskets allow oil to pool in the spark plug wells, oil can make its way inside the porcelain insulator and potentially affect plug performance, but this is true of far more modern plugs too.

I will be very curious to hear how the new set of Champions compares visually to the old ones in your engine and if any differences are apparent.

Cheers,

Don

Apparently the RC9YCC's are "new old stock" Don - from this supplier

https://www.gsparkplug.com/

Larry

Thanks for the tip, Larry!

I just ordered a couple of sets for fun. I would have ordered some RC12YCC too but they're out of stock, probably permanently. I would imagine their stock of RC9YCC won't last forever.

Thanks again!

Don

Did you go for "cheapest" shipping?

If you did, (like me) let's see who gets 'em first! :icon_playing:

Larry

Yep. And I would agree with your quotation marks around "cheapest." I think with my discount at NAPA I paid about USD $12.50 including sales tax for my last set of RC9YC, and these RC9YCC wound up costing about $22.00 per set with shipping. Maybe not worth the extra expense, but some of my friends in the Nashville British Car Club will like the idea of having the original type plugs in their engines.

BTW I have an '89 XJ-S V12 in the garage today, and I am thankful that I don't have to do a plug job on it right now! Although it's not really much more involved than doing the rear bank plugs on a lot of modern transverse V6s with the wrap-over intake manifolds.

Cheers,

Don

Larry,

I received an email notice today stating that my RC9YCC plugs have shipped. How about you?

Don

Mine shipped last Friday, but I'll bet you get yours first (Canada Post ...:icon_bike:)

Larry

Larry,

My package of 12 RC9YCC arrived yesterday. I was not pleased with the packaging - when I cut off the garbage-bag plastic wrap, two of the plugs fell out onto my bench (!), so take care when opening your package.

What I received was a larger box of 10 plugs, and two smaller boxes containing one individual plug each. These were the plugs that fell out of the ends of their boxes once the plastic bag was removed.

The plugs are clearly marked RC9YCC and are stamped "Made in France" in the metal.

The box of 10 reminded me that when I once purchased plugs from Jaguar, they came packaged in a box of five (5), which I though was very, very weird for a company known for its 6- and 12-cylinder engines (and later, V8s). This must have been a practice adopted from Champion, but the logic escapes me.

Cheers,

Don

Set of 5 eh? - makes total sense, Don!

Three possible reasons -

#1 - Britain went over to the decimal system in the late 60's and prior to the changeover, sparkplugs were sold just like eggs, by the dozen and half-dozen. In France today, if you need to pick up a few eggs for breakfast, you have to buy a pack of 10 because they don't do a pack of 5. Also, because it would upset the Chinese shoppers, they don't sell them in 4's as the number 4 is considered unlucky..

#2 - Brits generally drive 4-cylinder cars and Champion include an 'extra' plug in the package in case one drops on the floor and cracks due to bad shipping practices.

#3 - In the 1990's, Lexus came on the scene and in order to compete with the Japanese, Jaguar changed their inventories over to the Japanese cultural system where 5 items are considered a complete set.

Oh and I expect my plugs to arrive by mule train sometime next week if I'm lucky.

Larry

Mine came today Aug 7th, not bad, only 8 days after yours and of course I ordered them three days before you.

Packing was pretty good though, padded envelope, nice and snug. I got mine on their eBay site though, so maybe that made a difference?

Anyway, happy to have them!

Larry