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  1. #1

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    Fresh 4tec rebuild turning over slow, extremely hard to turn over by hand?

    I thought this nightmare project had finally come to an end. I just finished rebuilding my 2002 4tec motor. I did everything by the book and checked all tolerances. While a few were on the edge of within spec, they were. I did everything with the rings I was supposed to also. When I got the head back on and the timing set, I used the pump to turn it over several times to make sure nothing was hitting and all was well. Everything seemed to check out and I locked the crank and matched up the lines on the cam. With the plugs out all 3 cylinders have a decent amount of resistance from the springs, and then when it gets past TDC it springs down and you can hear the air rush into the cylinder through the spark plug hole. With the spark plugs in though, it's very hard to turn over using the socket in the pump. It was so hard, that I took the plugs out because I thought something was binding but it was fine. I used engine assembly lube and not motor oil to assemble because I knew it would sit for a couple months before it was finished. I put a thin layer of oil on the cylinder walls right before putting the head on. Is this normal with the plugs in? I'm afraid to try it with the starter until I hear if this is normal or not. Thanks in advance for any help!


  2. #2
    shrabber's Avatar
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    Should be very hard with wrench like I said here when properly built you have immediate seal and compression. Keep chucking along as long as both crank and cam were locked at the time of timming chain install and setup roll on hommie

  3. #3

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    OK thanks. I actually was using a 24" breaker bar. Hopefully the answer is the same though. It almost has to be compression, and if so, I did a damn good job lol. I was thinking to myself,"I feel like I did a pretty good job, but not THAT good." All I have to do is throw the valve cover back on and I'll try turning it over with the starter tomorrow.

  4. #4
    Boost addict hotbird's Avatar
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    sounds like its ok.

  5. #5

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    Failed to mention it also has brand new valve springs.

  6. #6
    mikelytle1077's Avatar
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    Crank it without the plugs holding the throttle wide open let the engine build some oil pressure. Then fire it up

  7. #7
    In my experience, when you assemble with assembly lube rather than oil, there will be quite a bit friction in the motor because of the lube

  8. #8
    SLASHER's Avatar
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    They are always slow to turn over after full rebuild ...

    I found with assembly lube it made it turn much easy ...

    Crank with throttle fully open and hold and crank to get oil to surculate then latter start and leave at idle ..

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