Broken Spark Plug Cap

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hppants

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Today I started taking my bike down for the valve check and CCT replacement. Got all of the plastic off, gas tank off, "T-brace", emissions stuff. Then I see it - the o-ring for the coolant tube between the #3 and #4 plug has been oozing for a while. Not enough to cause a drip, but coincidence or not, the #3 plug cap was stuck. I pulled the wire straight out - no biggie - I've done that before and it can be easily re-installed. But the cap was stuck and I ended up seperating the "threaded" part from the rest. The actual cap is still stuck to the spark plug. At this point, I'm hopeful that when I remove the cam cover, it will come undone.

So the question is - anybody have any luck with gluing the spark plug cap ruber together and if so, what did you use? Wonder if J-B Weld would work?

 
Always had really good results on rubber with superglue. The only other good result was my fingers
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On reassembly coat the ribs that contact the valve cover holes and the area the spark plug slides in with dielectric paste. They aren't likely to stick again.

 
Picked up some JB Weld. Doesn't say it works on rubber, but it's working temperature goes to 240 degrees. So I'm hopeful. We'll see what tomorrow brings. As long as I can get the wire re-installed in the cap, the only purchase purpose of the part that broke is to seal the hole, from what I can tell.

 
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I am not sure about JB Weld for that but I can't say it won't work. I agree that a thin film of grease where the caps pass through the valve cover gasket is beneficial. It seems almost as though the valve cover gasket "squishes" more on some of the holes than others. I had to grease the outside of the spark plug socket pretty good on two of the four holes when I changed Dad's last time.

 
I used some RTV on one as a temporary repair....... not to worry too much as that area is not subject to water intrusion, just need it as a dust cover. The final fix was a used coil on ebay that came with wires for $25.

 
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