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Thread: head bolts/lifter adjustment

  1. #1
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    head bolts/lifter adjustment

    Well in the process of changing the water pump, i did a pressure test of the cooling system once I had the intake removed as I have had a minor coolant leak that i couldnt find. Well found it and its at the seam of the heads and the block, pretty uniform and tiny. In reading I realized the heads have not been retorqued since the motor was redone, so I am believing this to be the issue. I have read in the manual the the angle method, I have read that there have been people that run the torque up to 80lbs. Is there a general value that is tried and true?? And what about the lifters as far as adjusting them, I dont know that they are especially noisy but then again I never heard the car run prior to getting the motor work done, so not sure what to expect regarding the sound of them.

    Thanks.

  2. #2
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    If the head gasket is leaking, re torquing isn't going to stop the leak. You could try Barr's Stop- leak but figure on replacing the head gaskets. The torquing method in the manual is supposed to be the final torquing method so you don't need to go back and retorque. In my experience, once you have a leak, over-tightening usually won't stop the leak but it will break and strip things.
    David Teitelbaum

  3. #3
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    Quote Originally Posted by David T View Post
    If the head gasket is leaking, re torquing isn't going to stop the leak. You could try Barr's Stop- leak but figure on replacing the head gaskets. The torquing method in the manual is supposed to be the final torquing method so you don't need to go back and retorque. In my experience, once you have a leak, over-tightening usually won't stop the leak but it will break and strip things.
    Thank you dave, I did retorque and the leaks are gone. Also found the intake bolts to be a little loose likely causing vacuum leak. After swapping the water pump, retorquing the heads and reassembling It runs better. I was able to run it but now it does have an issue with restarting when it is hot. There is pressure on the plate, indicating fuel pressure. I am going to attempt to do the dwell test/setting of the CO.

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    If re-torquing worked it means the head wasn't torqued properly in the first place. If the hot start problem persists try the "plug swap". The fix will turn out to be either;
    the accumulator
    the check valve on the fuel pump
    the PPR
    A fuel leak
    David Teitelbaum

  5. #5
    Senior Member DMC-81's Avatar
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    Quote Originally Posted by David T View Post
    If re-torquing worked it means the head wasn't torqued properly in the first place. If the hot start problem persists try the "plug swap". The fix will turn out to be either;
    the accumulator
    the check valve on the fuel pump
    the PPR
    A fuel leak
    David, for your information, in the Workshop Manual in the Changing Cylinder Head Gaskets section it expressly states in C:05:07 to:
    - Run the engine for 30 minutes
    - Let the engine cool down for at least 2 hours then retighten the cylinder head.


    The heat cycle is needed for the gasket material to properly bed, then a re-tighten.
    Dana

    1981 DeLorean DMC-12 (5 Speed, Gas Flap, Black Interior, Windshield Antenna, Dark Gray)
    Restored as "mostly correct, but with flaws corrected". Pictures and comments of my restoration are in the albums section on my profile.
    1985 Chevrolet Corvette, Z51, 4+3 manual
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    2010 Camaro SS (Transformers Edition)

  6. #6
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    I assumed he did the procedure properly and had the leak AFTER the retorque. I was mistaken. Obviously he did not do the complete torquing procedure.
    David Teitelbaum

  7. #7
    Administrator Ron's Avatar
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    $.02
    Retorque depends on the gasket.
    Some manufactures say you must, some say not to, and, some can be either way, but require a different sequence etc.

  8. #8
    Senior Member DMC-81's Avatar
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    Quote Originally Posted by David T View Post
    I assumed he did the procedure properly and had the leak AFTER the retorque. I was mistaken. Obviously he did not do the complete torquing procedure.
    Fair enough, but I think he was pretty clear:
    Quote Originally Posted by northeast dmc View Post
    Well in the process of changing the water pump, i did a pressure test of the cooling system once I had the intake removed as I have had a minor coolant leak that i couldnt find. Well found it and its at the seam of the heads and the block, pretty uniform and tiny. In reading I realized the heads have not been retorqued since the motor was redone, so I am believing this to be the issue. I have read in the manual the the angle method, I have read that there have been people that run the torque up to 80lbs. Is there a general value that is tried and true?? And what about the lifters as far as adjusting them, I dont know that they are especially noisy but then again I never heard the car run prior to getting the motor work done, so not sure what to expect regarding the sound of them.

    Thanks.
    In the end, re-torquing was apparently the issue.

    Quote Originally Posted by Ron View Post
    $.02
    Retorque depends on the gasket.
    Some manufactures say you must, some say not to, and, some can be either way, but require a different sequence etc.
    Agreed. I recently helped choose between Austin's selection of 3 or 4 different head gasket versions that he bought from different vendors. Some came with their own instructions and some didn't. If they don't, I'd stick to the Workshop Manual procedure.
    Dana

    1981 DeLorean DMC-12 (5 Speed, Gas Flap, Black Interior, Windshield Antenna, Dark Gray)
    Restored as "mostly correct, but with flaws corrected". Pictures and comments of my restoration are in the albums section on my profile.
    1985 Chevrolet Corvette, Z51, 4+3 manual
    2006 Dodge Magnum R/T (D/D)
    2010 Camaro SS (Transformers Edition)

  9. #9
    Motors about after dark Michael's Avatar
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  10. #10
    Administrator Ron's Avatar
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    Quote Originally Posted by DMC-81 View Post
    Agreed. I recently helped choose between Austin's selection of 3 or 4 different head gasket versions that he bought from different vendors. Some came with their own instructions and some didn't. If they don't, I'd stick to the Workshop Manual procedure.
    Anything that important should have specs included. If they don't and are not OEM, I would send them back to the supplier.

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