Is it bad to use Dust-Off (compressed gas duster used for keyboards) to blow away dirt on the cylinder head around old plug before removing? And, is it really necessary to use the anti-seize compound when replacing plugs?
It's definitely not necessary, but it can't hurt to do so. Any time you have metal threads, especially directly on an engine block, it's not worth it to take chances. I use Pedro's anti sieze compound, it's made for mountain bikes, but it's all I had on hand and it seems to work well.
I recomend it... In fact on my eli the saprk plugs are in a hole amd that collect water from rain etc and the cam chain tunnel is on the left forcing water puddles in the cylinder 1 and 2 and sometimes 3 cylinder. I have to get rid of it with air and those cans aren't enough... I use paper towels and cloth that has beed cut into strips etc to get it out... and you have to before riding... else it turns into steam and pops off the spark plug cap.
Cool.
Srinath.
I try to brush-down the area around the plug with a toothbrush, then blow it with canned air, then finish with a vacuum cleaner: I put the end of a 1" hose down around the plug itself, so that it covers the plug hole. Sounds long, but really only takes 30 seconds.
For my VW, I made a vacuum straw (kinda like at the dentist) to get down into the deep wells and vacuum out around the plugs before I pull them. All sortsa crud collects down there.
You should use high temp anti-seize on things like plugs and exhaust header bolts - those areas are hot! I doubt mountain bike anti-seize will last more than about 15 seconds after the engine starts.
I personally never use anti-seize on plugs, and have never had a problem. The plugs are plated to avoid seizing. It could also potentially lead to stripping the head, since the anti-seize will act as a lubricant, and lower torques will result in much higher thread loads.