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valve slash

Discussion in 'Performance and Tuning' started by joselito76, Nov 4, 2012.

  1. joselito76

    joselito76 [OP] Member

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    so I did a compression test today and I got 150,150,145,and 150 that looks a bit low, I belive by the repair manual the normal compression is between 180 and 160 if I remember clearly.My question is if a valve slash would be worth doing to get some of the compression back or I should just get a new head or a low millage used head. My other option is to strip the head take it to a m8chine shop get it back to spec and install everything my self use what ever can be use and replace what ever need to be replace. So what do you guys think.thanks in advance.
     
  2. Torspd

    Torspd Tor-nication

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    I say start with the cheapest option first. Then if you can adjust the valves. Do so, then check the compression again. I would also do a leak down test after that. If your restored your compression but the cylinders don't hold the compression, then it means your rings are worn out.

    That will all give you a better idea of what all needs to be done or not.
     
  3. joselito76

    joselito76 [OP] Member

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    true,true. thanks torspd. One more thing how do you do a leak down test
    i just google it got it thanks
     
  4. 06SR5canada

    06SR5canada Well-Known Member

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    Pretty sure it's called valve LASH lol
     
  5. Gadget@URD

    Gadget@URD Well-Known Member Vendor

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    I would not worry to much. The balance between the cylinders is what is important. The actual number is a bit low, but it could be from gauge error. I have several compression testers in my shop and have seen a 25 psi variation between them when used back to back on the same engine.

    Did you prop the throttle valve open during the test?

    It will not hurt anything to check the valve lash. If it is out of spec then thing about doing the adjustment.

    G
     
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