Rep Power: 0

So after doing some research here I think my head gasket is failing but i just want to get some confirmation before I start doing anything. My car is a 2004 Civic EX manual with 157,000 miles.

Here is some history so that I don't forget anything.

Last year the oil pan decided to start leaking so brought it to the garage and got it resealed. Then before Christmas oil started disappearing again. Brought it back to the garage about a month ago and it turned out the oil pump seals had to be replaced. $1060 later and the oil leaks were gone.

On Friday 28th Feb I got my smog check done, it passed but mechanic there told me there was a slight miss at higher rpm. The following Sunday after driving 15 miles on the freeway I then had to drive another mile or 2 at 10-20mph. As I pulled into the drive way I noticed the temp gauge was higher than normal, instead if being just below the little temperature symbol it was a little above it. I immediately turned off the engine and let it cool. When i checked opened the radiator a blast of air came out and I could see down into the radiator a little. Checked the over flow bottle and it was almost full to the cap. I started the car and let it warm up and it didn't over heat again. Radiator filled up again so i thought it was just an air lock or something.

Car ran fine until Friday when after half an hour of freeway driving I pulled into work. As i parked the car, again the temp gauge was up higher than normal. Let it cool again, and when i opened the radiator the same thing happened. Blast of air and overflow bottle almost full to the cap. This time I could see a little dampness on the outside of the overflow bottle. I also checked the oil and my oil has disappeared again, it was just tipping the bottom of the dip stick. So got some oil and got home safely. Opened the radiator cap again and a little air came out, water was higher than last time.

So yesterday, I took out the spark plugs to see if I could see anything wrong with them. Here are pics of each spark plug. I could see that one of them was a bit more worn than the other. The spark plugs are about 1 year and 3 months old and are NKG Iridium IX.



I didn't get a chance to check if I could see oil in the coolant but i will keep an eye on it. If I missed anything just ask.

 
Rep Power: 210

what you are describing are definite signs of a head gasket failure,....whatever you do, DO NOT let the engine overheat or you will need a new head along with the gasket

 
Rep Power: 519

You will not find coolant in the oil.

Plugs look useable.

Engine needs the head gasket job.

 
Rep Power: 519

Side note: Plugs look like they were not properly tightened.... the gaskets don't look like they got squashed and it looks like carbon is climbing the threads.

 
Rep Power: 0

As I feared, and I don't have the time and space to do it myself

How tight should the spark plugs be tightened?

Also, I was looking for oil in the coolant and the video made me rofl.

 
Rep Power: 519

Tighter than what those were?



Printed specs:

NGK: No anti-seize and torque to 18-21 ft-lb (flat seat, with gasket, 14mm threads, aluminum head)

Honda: Apply a small amount of anti-seize to the plug threads, and torque to 13 ft-lb.



NGK:
http://www.ngksparkplugs.com/tech_su...x.asp?mode=nml



Take your pick.
I do it entirely by feel, and I use anti-seize.

 
Rep Power: 0

Yup. Funny that NGK specifies no anti-seize for their plugs, when their subsidiary NTK packs their O2 and A/F sensors with two kinds (gray already on threads, and a packet of copper stuff)...

The torque spec can vary, as not every manufacturer has the exact number of threads in the plug hole. If Honda specifies a lower torque spec with anti-seize (which allows more accurate torque, technically), I'd follow it. BTW I've also done all of my plugs by feel after years as a tech as well.

 
Rep Power: 519

I think most manufacturers apply the stuff on new sensors as they are packaged, it only makes sense since they go in the exhaust and may eventually need to be removed again.

I've never seen them come with extra though.
Maybe added by a reseller/reboxer?
IDK

 
Rep Power: 0

Sort of makes sense to package spark plugs the same way (esp if they're good for 100K like OEM Denso plugs are)... not sure why they don't, as they're closer to high heat and pressure than the sensors are (if maybe not road salt and water).

The genuine NTK O2 sensor for the old Escort, and the Denso LAF sensor in the Civic, both had a smear of gray conventional moly on the threads under a protective cover, and a tiny tear packet of copper antiseize separately in the box (both were not Ford/Honda packaging, but direct manufacturer versions of plug spec, in their packaging). On both I just applied both kinds sparingly before torquing them in.

 
Rep Power: 519

Quote:

not sure why they don't, as they're closer to high heat and pressure

Why NGK says anti-seize isn't needed:


http://www.ngksparkplugs.com/pdf/TB-...1antisieze.pdf

"All NGK Spark Plugs are manufactured with a special trivalent Zinc chromate shell plating that is designed to prevent both corrosion and seizure to the cylinder head; Thus eliminating the need for any thread compounds or lubricants."




Nonetheless, Honda still says to use it.

 
Rep Power: 210

in over 25 years working on all different types of engine i have never used a torque wrench on a spark plug, i just go by feel, but if your not sure then go by the specs