给xxhhwxc，关于valve seal

楼下帖子都快刷屏了，我另开新贴。我说的就是 valve seal (or valve stem seal)，不是piston ring seal。valve seal 就是一调节seal，而不是起完全密封作用。engine工作时需要少量油来润滑valve stem(我原帖写的是piston ring，记错了，引起误会）。如果该seal老化，过多的oil 下流而导致气缸烧机油，从而产生蓝或黑烟。对楼下车主来说，只要烧机油有限，而且engine performance没什么变化，问题可以放一放。
我顺便把我学车是的教材上的关于valve seal 的讲述发在这儿以供参考。注意下图中的红线部分。

所有跟帖： 

• you are right -xxhhwxc- ♂ (170 bytes) () 08/04/2010 postreply 16:08:34

• have you changed the seals? -隐睾- ♂ (0 bytes) () 08/05/2010 postreply 09:52:22

• yes -xxhhwxc- ♂ (49 bytes) () 08/05/2010 postreply 10:35:35

• have you changed the seals? -隐睾- ♂ (0 bytes) () 08/04/2010 postreply 16:22:06

• No. Valve job needs some special tools. -biglow- ♂ (0 bytes) () 08/04/2010 postreply 20:56:43

• you just need a valve spring compressor -xxhhwxc- ♂ (34 bytes) () 08/05/2010 postreply 10:38:08

• 回复：给xxhhwxc，关于valve seal -乱猜- ♂ (249 bytes) () 08/04/2010 postreply 20:13:15

• Thanks Biglow!! my valve seal issue -wenxue06- ♀ (501 bytes) () 08/05/2010 postreply 09:11:40

• Go to a shop if you have too much money to throw away -xxhhwxc- ♂ (237 bytes) () 08/05/2010 postreply 10:44:03

• Super Thanks! I will check it often -wenxue06- ♀ (37 bytes) () 08/05/2010 postreply 11:18:33

• If car needs 1 qt oil every 500 miles, it probably -khyang86- ♂ (198 bytes) () 08/05/2010 postreply 11:18:59

• 回复：If car needs 1 qt oil every 500 miles, it probably -Yangtze430030- ♂ (105 bytes) () 08/05/2010 postreply 12:19:48

• 回复：回复：If car needs 1 qt oil every 500 miles, it probably -khyang86- ♂ (397 bytes) () 08/06/2010 postreply 10:25:02