Spark plug drain hole

3 replies to this topic
  • jmw00

Posted June 01, 2004 - 05:28 AM


This will be my first post. up until this point i have found all the answers i needed without a post. This is a great site :thumbsup:. ok here is my question... From what i have been reading the small hole on the block is the spark plug drainage hole is that correct? After riding my bike (00' 426 no modifications) there is a small amount of dark liquid could be oil coming from the hole, it is only enough to make it a couple of inches down the block.. This is probally nothing but just wanted to check and make sure. I bought the bike used about 3 months ago. Any and all input would be greatly appreciated.

  • twistngrip

Posted June 01, 2004 - 06:21 AM


I am assuming the 426 is the same as the 450 in this respect. The hole on the right side of the cylinder head is the spark plug drain hole. Part of the cylinder head cover gasket forms a seal between the hole that the spark plug is located in and the cylinder head cover. You probably have a small amount of oil leaking past the gasket and down into the spark plug area then out the drain hole. You could pull the spark plug wire out, spray some electrical contact cleaner down in there and wash it out. (The cleaner and oil, dirt etc. will come out the drain hole). Then observe it for a ride or so and see if there is enough of a leak to warrant further action. If it is leaking enough to matter, then you need to take the cylinder head cover off and check the gasket to make sure it is seated correctly and then either reseat the gasket or replace it. That is a very simple job. If the leakage has you scared, don't worry, it is no big problem. :thumbsup:

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  • jmw00

Posted June 01, 2004 - 06:27 AM


Thanks man that is exactly what i needed to hear :thumbsup:

  • Fastest1

Posted June 01, 2004 - 07:56 AM


Could even be a loose spark plug.

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