[xj-s] Head Off

["Kirbert" <palmk@mailer.gadcomm.net>]

As mentioned in another message, my A bank head is off.  The guilty 
valve seat has dropped and cocked sideways, holding the intake valve 
open.

I dunno about you guys, but I find the fact that it cocked sideways 
interesting.  It almost makes one think it must have been REALLY 
loose; just loose enough to SLIDE out would seem to prevent cocking, 
it would have needed to be seriously loose to cock.  But upon further 
reflection, I suspect that it simply slid down until the closing 
valve tried to push it back up, and THAT'S what cocked it.  Probably 
galled the recess a little bit.

Lemme tell you how close this intake valve came to the top of my 
piston.  As with most engines that have some miles on them, the tops 
of my pistons have a thin layer of hard carbon deposits covered by a 
somewhat thicker layer of soft deposits.  There were valve marks in 
the soft deposits!  Had me thinking I might be in serious trouble 
until I wiped my finger across the mark and all the soft deposits 
wiped right off, leaving no indication of impact on the hard 
deposits.  Just to be doubly sure, I then scraped all the hard 
deposits off and confirmed that the piston itself seems totally 
intact and unaffected.

Tomorrow I'm gonna get my hands on a valve spring compressor and pull 
this intake valve out and see what it looks like.  Offhand, I'm 
tempted to just order a new one anyway.  I'm also gonna start calling 
machine shops, and ask them if I need to get a replacement seat and 
valve or whether they get them.

 -- Kirbert      |     If anything is to be accomplished,
                 |     some rules must be broken.
                 |          - Palm's Postulate

---

• Prev by Date: [xj-s] Plugged Rads
• Next by Date: Re: [xj-s] Share the knowledge
• Prev by thread: Re: [xj-s] Plugged Rads
• Next by thread: Re: [xj-s] Head Pulling
• Index(es):
  • Main
  • Thread