What is normal Spark Plug Insulator Color ?
#1
11-08-2015, 08:54 PM
What is normal Spark Plug Insulator Color ?
I have a (new to me) 2000 XK8 that I am going thru revitalization after several years of storage. I pulled the spark plugs today and was surprised that they basically look new other than light carbon around the base of the threads. I had already purchased a set of new NGK Iridiums so I'll replace them anyway.
According to PO and records the plugs have not been replaced. Car has 95,000 miles. My question is: The left bank plugs all have bright white insulators, and the right bank are all very very light tan. I am used to seeing some color on the insulator. Is this lack of color normal ?
There is no evidence of overtemperature or blistering on the plugs. Using a scope to look at the top of the pistons there is a light coating of carbon and you can still see the triangle (or is it an "A" ?) clearly, and again no indication of overtemperature.
According to PO and records the plugs have not been replaced. Car has 95,000 miles. My question is: The left bank plugs all have bright white insulators, and the right bank are all very very light tan. I am used to seeing some color on the insulator. Is this lack of color normal ?
There is no evidence of overtemperature or blistering on the plugs. Using a scope to look at the top of the pistons there is a light coating of carbon and you can still see the triangle (or is it an "A" ?) clearly, and again no indication of overtemperature.
