Welcome to Club Hot Rod!  The premier site for everything to do with Hot Rod, Customs, Low Riders, Rat Rods, and more. 

  •  » Members from all over the US and the world!
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and hundreds of thousands of posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

 

Thread: zilch for compression on #1
          
   
   

Reply To Thread
Results 1 to 6 of 6
  1. 10-01-2015 08:17 PM #1
    TOW'D
    TOW'D is offline CHR Member/Contributor
    Visit my Photo Gallery
    Join Date
    Feb 2004
    Location
    Bella Coola
    Car Year, Make, Model: 1948 Thames E83W- and many others
    Posts
    789

    zilch for compression on #1

     



    Hi Gang,
    I did a compression test on a GMC 7.4L in a pleasure boat.
    All except #1 were close to 180 psi
    #1 was zero
    I put the crank on #1 TDC and put shop air into spark plug hole and we can hear air leaking out the throttle body.
    Today I pulled that head off .
    The exhaust valve looks like it has a nice shiny surface where it seats but the intake doesn't.
    All the push rods look good.
    I'll do a valve grind.

    my question
    Are the head bolts reusable?
    thanks
    Hank
    Reply With Quote Reply With Quote
  3. 10-02-2015 07:51 AM #2
    stovens's Avatar
    stovens
    stovens is offline CHR Member
    Visit my Photo Gallery
    Join Date
    Oct 2007
    Location
    Petaluma
    Car Year, Make, Model: 48 Ford F1
    Posts
    9,778

    Not sure Hank, but here to hear, what others will say. Just a thought but could it be a cam lobe issue, or just not seating properly?
    " "No matter where you go, there you are!" Steve.
    Reply With Quote Reply With Quote
  4. 10-02-2015 09:31 AM #3
    rspears's Avatar
    rspears
    rspears is offline CHR Member/Contributor
    Visit my Photo Gallery
    Join Date
    Sep 2007
    Location
    Gardner, KS
    Car Year, Make, Model: '33 HiBoy Coupe, '32 HiBoy Roadster
    Posts
    11,010

    Are you asking because of the widespread discussion about Gen II and newer head bolts being TTY because they spec an initial low torque, followed by an angular final tightening in sequence?
    Roger
    Enjoy the little things in life, and you may look back one day and realize that they were really the BIG things.
    Reply With Quote Reply With Quote
  5. 10-02-2015 02:29 PM #4
    jerry clayton's Avatar
    jerry clayton
    jerry clayton is offline CHR Member
    Visit my Photo Gallery
    Join Date
    Feb 2006
    Location
    Bartlett
    Posts
    6,831

    7.4 are reusable
    Reply With Quote Reply With Quote
  6. 10-02-2015 07:43 PM #5
    TOW'D
    TOW'D is offline CHR Member/Contributor
    Visit my Photo Gallery
    Join Date
    Feb 2004
    Location
    Bella Coola
    Car Year, Make, Model: 1948 Thames E83W- and many others
    Posts
    789

    thanks guys
    I tested the head with water resting in the combustion chamber and it leaked past the intake valve on #1
    yes I was wondering about the TTY bolts good to know they are Not used

    cheers
    Hank
    Reply With Quote Reply With Quote
  7. 10-13-2015 07:40 AM #6
    TOW'D
    TOW'D is offline CHR Member/Contributor
    Visit my Photo Gallery
    Join Date
    Feb 2004
    Location
    Bella Coola
    Car Year, Make, Model: 1948 Thames E83W- and many others
    Posts
    789

    What kind of thread sealant do you guys use on the head bolts ?
    It seems that the shorter bolts are exposed to the antifreeze.
    thanks
    Hank
    Reply With Quote Reply With Quote
Reply To Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts

Forum Rules

Links monetized by VigLink