4th spark plug

I installed a new spark plugs for my chevrolet cruze 2012 i followed this method first tighten them by hand until stops then a wrench also untill stops and lastly final tighten from 3 to 6 oclock . On 4th spark plug i followed first 2 steps ok but then 3rd step it tighten only from 3 to 4 oclock the other 3 plugs i did the 3 to 6 ok and then i was able to do a little more tight on them but not the 4th plug . The engine runs fine i think

Where did you learn this method of tightening spark plugs?

Tester

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That method is a new one on me too. If you want to get it right, then you use a torque wrench.

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In some applications a torque wrench can’t be used for the final torque.

This is how it’s done.

Tester

Your guide suggests essentially the exact method the OP used. This a gasket type plug with aluminum heads.

What applications? Your guide has torque specs for all applications.

That’s a 1/4 turn.

The instructions I provided doesn’t show that step.

and requires one-sixteenth (1/16) turn.

will require â…ś-â…ť turn

The article also states, “If using a torque wrench”

On some vehicles you can’t.

Tester

Fair point.

That’s not from the article I provided.

Who provided that information?

And, is that for a tapered seat spark plug? Or a gasket seat spark plug?

Tester

If I had this problem I’d measure the engine compression and if all cylinders passed I’d leave well-enough alone. If number 4 showed low compression, I’d remove the plug again and see if there’s something wrong with either the plug’s threads or the cylinder head threads. If there’s a problem it’s usually possible to repair the threads, but may require specialist equipment that your shop will usually have. Suggest to not force anything and don’t try to effect a repair without access the necessary specialist equipment.

FWIW, diy’er-me doesn’t tighten spark plugs using that method. I screw them in by hand until they begin to seat, then just snug them up by feel. I have used a torque wrench for this on occassion, but I found I can do it just as accurately by feel.

As far as I can tell the torque spec on the Cruze plugs is 18 ft.lb.

Even the Champion site linked keeps saying: Note: If using a torque wrench, please refer to the Torque Recommendations chart below."

Anyway. I’d imagine that @Mariah234765 ’ s plugs are just fine. Except that I’d be tempted to make sure that the 4th plug didn’t lose its crush washer. But if there’s no obvious problem (including no “Tick or squeak noise from engine”), then let it ride.

Once in my life I had a spark plug work loose. (Tapered seat rather than crush washer). I probably just spaced out and didn’t tighten it up after finger tight. Don’t recall. But there is no instant disaster. It was an easy find and fix.

The real drag would be if the threads in the head get stripped out. That whole 3-6 o’clock turn would worry me.

A carbon film on the spark plug hole threads can cause increased resistance while tightening the spark plug, making the last bit of tightening difficult. Shouldn’t be a problem, I wouldn’t worry about it.

Here is the 1/4 turn thing… Gasket Type*…

That equals a 1/4 turn

Yeah, I know. Thanks. After finger tight and wrench tight (going by the OP - that would be when the washer is crushed, I guess) - 1/4 turn is a lot. Aluminum heads. I can feel the threads stripping out now. After finger and then wrench tight? 1/4 turn is WAY past 18 ft. lb.

LOL. " The content contained in this article is for entertainment and informational purposes only"

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I think you guessed wrong,
To me wrench tight would be snugged up before crushing the washer, then a 1/4 turn.
I’m guessing that because that is how I’ve always done washer type spark plugs.

It is. Scroll down to the bottom of your Champion article. It’s for aluminum heads and gasket seat.

Look at the screenshot I posted again, it is also for cast iron head and gasket seat…

Same here. Except I think the term “wrench tight” is asking for trouble. Ask 5 people and you may get 5 different answers. I personally know some people who’s inner Arnold come out when asked to tighten something with a wrench :grinning:

I would say 1/4 turn after gasket contact.
But I’ve used feel all my life and never had anything come loose or fail in use. I can easily tell when the gasket has stopped compressing. No sense going beyond that, you’re defeating the purpose of the gasket and just deforming things beyond that point…