Compression Past the Spark Plug

[yorgeyr]

Im having compression past the spark plug on # 4 . I did this attempting switch my spark plug. How would go about fixing this ???

 

[yavapaires]

Does this engine have aluminum heads? If it does, I am afraid you probably stripped the sparkplug threads. There is a repair for this. You should be able to get a kit at your local parts house. If you have cast iron heads, you probably cross threaded the plug when you put it in.

 

[yorgeyr]

aluminum heads

 

[yavapaires]

When you removed the plug, did you notice aluminum in the threads?

 

[yorgeyr]

i just removed it right now and i cant really tell if theres aluminum in the threads, it doesnt look like it but there could be .... the only i really notice about the plugs is that theres small imprefection on the treads

 

[yavapaires]

I'm willling to bet the small imperfections you see is aluminum. At this point you really have nothing to loose by cleaning the threads, applying some antisieze compound and putting the plug back in. Tighten it snug, then tighten just a little bit more, no more than 1/16 turn. If plug feels OK then start it up and see what happens. If plug won't tighten, then you will have to repair the threads in the head.

 

[drbenz]

You might consider going to the parts house and buy an inexpensive rethreading tap made for spark plugs (make sure to buy the correct one) that has a 3/8 square hole in the top of it. Insert a 3/8 extention of an apropriate length (short enough not to get in the way and long enough to have turning room with a ratchet) and retap the plug hole threads. Make sure that you are straight with the hole and go slow so you can feel if you are cleaning out the old threads (good) or trying to make new ones (bad)!