Spark Plug Changing

[xanthinic12]

91,b6,efi,auto....

ok, i've mastered the art of changing oil, without getting covered completly in it. i bought some bosch platnium plus (on sale). is it as easy as it seems, remove, put some anti seize on it and put it in. are there any tricks that i should know about?

[scottxd45]

Don't forget to gap the new plugs & twist the spark plug wire boots back and forth a few times before pulling them off to avoided ripping the innards out if it is seized onto the plug. Oh and I have never put anti seize on them before but I guess it wouldn't hurt as long as that would not effect conductivity and not let it ground properly but I have no idea. Someone on here will though I'm sure.

[xanthinic12]

Gap? huh that little thing that kinda looks like a half dollar? and to what size.

[scottxd45]

You have to set the gap between the electrode and the ground. You can get a gapping tool really cheap at any parts store. You should be able to find the gap on the sticker on the inside on the hood if it is still there. If you don't have the sticker tell me the year/engine and I'll look it up for you.

[xanthinic12]

1991 mazda 323 b6, bought the engine of another user here, never have seen the acutal car it came out of, thanks alot.

[scottxd45]

Spark Plug Gap - 0.039-0.043 in

[xanthinic12]

Thanks alot, really apreciated

[jglutz]

Always best to pull the plugs when the head is warm....Be carefull...you can burn your self if you just turned the engine off.
Let it run for 10-15 minutes then wait another 10-15 minutes. They will break lose alot easier when warm.

When installing the new plugs...I start them by hand for the first couple of threads/turns....provides a level of comfort that they are starting properly.

Anti-sieze is a great idea...not much is required...be sure to place a little at the end of the threads...hex end..at the sealing surface where the plug bottms out.

[FB71]

Always best to pull the plugs when the head is warm....Be carefull...you can burn your self if you just turned the engine off.
Let it run for 10-15 minutes then wait another 10-15 minutes. They will break lose alot easier when warm.

When installing the new plugs...I start them by hand for the first couple of threads/turns....provides a level of comfort that they are starting properly.

Anti-sieze is a great idea...not much is required...be sure to place a little at the end of the threads...hex end..at the sealing surface where the plug bottms out.

Joe,

Ford has specifically said in service publications and technical bulletins to NOT remove spark plugs from a warm engine. Engine should be COLD (ambient temp). While it's tempting to remove the plugs while warm, because of thermal expansion, you run a much greater risk of stripping the threads out of the head. If the plugs do not want to turn without excessive effort, a propane torch should be used gently heat the head near the plug while cooling the plug with compressed air. The issue is the threads soften when warm, and can stick to the plug threads from galvanic corrosion. Heating the head induces thermal expansion, but cooling the plug keeps the threads in the cool as well.

[gottafesty]

When installing the new plugs...I start them by hand for the first couple of threads/turns....provides a level of comfort that they are starting properly.

To me this is the most important part. I have a brother that is notorious for cross-threading anything and everything from drain plugs to spark plugs. By all means start them by hand. My Dad likes to attach a short piece of vacuum hose to the spark plug. I just use the socket and extension with my fingers until finger tight. Then I grab the ratchet. I've never cross-threaded one yet, but I had to deal with one that had been cross-threaded on a previous car. It's a real pain after that's been done. Also, make sure you get them seated all the way in.

[sasquatch]

i heard that you should wrap the threads in 1 layer of making tape, i thought is was bull poop... is this true?

[gottafesty]

I never have.

[leapin]

After gapping I just put em in. Never had trouble yet.

[scitzz]

Jim is too right, do it cold. I have never heard of masking tape, but I really really really wouldn't. I think the idea would be the same as the antiseize, but seems to me it could create a pressure leak in the cylinder....

[jglutz]

Aluminum, the head material...fails equally, but differently, at temp extremes. While hot the yeild is lower, threads will shear easier. While cold the embrittlement lowers. It's a catch 22.

The reason I prefer warm...once the plug is cracked loose...it should spin freely the remainder of the way.
When cold...the thread could be tight the remainde of the way out...it then hard to tell if the difficulty is normal or am I jacking some part of the thread with the plug. Also galvonic ionization (corrossion caudsed by two dissimilar metal touching) is proprtional to many factors, specifically inversely proportional to temp). Mean as the temp increases the bond strengthe decreases.

Thou the above (me) is alot of academic crap....99.99% of plugs that come out bad....were never properly installed or sat for a long time and rusted within the combustion chamber.