1. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    Has anyone else had issues with head bolts backing off? As in the threads keep pulling out of the cylinders? Seems if a bolt hole was fine. A few 1000k's later, they will be stripped.

    I've kinda solved the problem with the next size up SAE hardware-with a crap load of washers(all I could get locally).

    Maybe the meal of my old cylinders wasn't the best casting?
  2. mati0921

    mati0921 Loyal Comrade

    Don't ever tighten more than 45 nm. it seems like not much, but i have stripped threads at 50 nm...
    check them again after a test run or it will blow gaskets in short time... i have blown them in as little as 2000 km once, because i was too lazy to take it apart to re tighten them. :)

    I saved one of the thrads by getting a longer stud and threading it all the way to the bottom of the hole. :)
  3. A Spooky Ghost

    A Spooky Ghost Loyal Comrade

    My guess is numerous folks through the years torqued them way pass 45nm. Other than re drilling/ tapping them. Your fix is the easiest, use longer bolts.. Should've done this last year before drilling 2 out for larger stuff. Our hardware store now has these longer ones in. Metric bolts, in person- are a bit of a dark art here state side.... Even the tool selection too. Most common wrench sets skip 9,11,16,18mm. Socket sets don't....:rolleyes:
  4. RogerDerSchrauber

    RogerDerSchrauber Premium Member Forum Donor

    Generally anytime you undo the cylinder head bolts, you have to retighten them (always with a torque wrench to the right specs) again after 200 km. In your case, having had many hands go through your Trabi’s motor over the years, the threads are probably pretty tired...

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