I had a leaky intake valve so I took that cylinder head off to grind it. Before grinding, I tested that it was indeed leaking and that the other two cylinders in the head did not by setting it on bricks and pouring water into the intake manifold. Indeed, the leaky cylinder leaked something like 45% of the 100-ish ml of water that I poured into it while the other two didn't leak literally a drop.

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After grinding, I tested the cylinder again using the same method to make sure it does not leak water over the same time period. However, I would like to test it in the installation before committing to the new head gasket and bolts I just bought. Does it make sense to torque the head using the old gasket and the old bolts just to test, using a cylinder leakdown tester kit and an air compressor and then, if alright remove it again and reinstall it with the get gasket/bolts? Or should I just put everything new assuming it will pass the test and then just leave it on. Another way to ask is, I guess, if I put the new gasket/bolts in and there is a leak again, will the new gasket/bolts be compromised for a reinstallation?

  • If you use the old gasket, and the gasket leaks, you will then be wondering if there is an issue with the head or the gasket.
    – HandyHowie
    Jan 5, 2022 at 7:10
  • Your method for testing is completely wrong. First, you should use IPA or something much thinner than water to test. Second, you should be putting the liquid on the chamber side, not the port side, to test. There's two reasons for this: 1) because that's where the pressure comes from during the 4-stroke cycle; 2) you can test both intake and exhaust valves at the same time. Jan 5, 2022 at 10:49
  • @Pᴀᴜʟsᴛᴇʀ2 -- i specifically do not want to test both at the same time because, in testing, you want to be as specific as possibly as to what you are testing -- because if one side leaked you wouldn't know which one
    – amphibient
    Jan 5, 2022 at 21:02
  • water is cheaper than IPA
    – amphibient
    Jan 5, 2022 at 21:03


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