Hello everyone, I just had a somewhat odd experience and I thought sharing it may be helpful to someone at some point and could save an unnecessary engine rebuild or replacement or even save an otherwise okay car from being scrapped.
Long story short, I bought a 353,000 mile 1997 Honda Civic 1.6 very cheap from a friend's brother because someone he knew severely overheated it, causing the timing cover to melt and jam the belt to the point of jumping several teeth and no longer starting. While he was trying to diagnose the problem, he blew out the ignition coil by cranking the engine with the spark plug wires off and decided he had enough after it sat for over a year and was going to scrap it, so I made an offer expecting to have to rebuild or replace the engine and here we are.
Having quite a bit of Honda experience, I immediately had an idea of what likely happened when I saw the melted timing cover and belt covered in melted plastic, so I checked the timing and found that it was off. Once I reset the timing and replaced the dead ignition coil with a spare I had, I tried starting it. Sounded like it had virtually no compression, it didn't even attempt to fire despite having fuel, proper timing, and spark. Starting fluid didn't help nor did cranking it at wide open throttle with the fuel injectors unplugged to clear any possible flooding.
Somewhat disappointed but not surprised, I got out my compression gauge and tested each cylinder and got 95, 165, 70, 70. That explains why it didn't start. I then added 2 cap fulls of oil to each cylinder, briefly cranked the engine, and retested the compression. This time, I got 120, 215, 90, 130. Feeling pretty confident that would be enough for the engine to run, I put the spark plugs back in, plugged in the fuel injectors, and tried starting it and it fired right up and ran well! I quickly drove it around the block without incident, the compression no longer sounds bad/uneven while cranking, and it starts right up now. I haven't retested compression yet because of the sketchy timing belt though. I ordered a new belt and will retest the compression once the belt arrives and I have a chance to change it and whatever other timing components were damaged.
I always knew that the oil film on the cylinder walls helps seal the rings by filling in the microscopic gaps, but this is the first time I saw an engine lose so much compression it sounded blown and wouldn't even attempt to fire just because someone flooded it months back and washed the oil off the cylinder walls. I had no idea that was even possible and I have been working on cars my whole life.
Anyways, just thought I'd share that odd experience in case anyone else runs across an engine that doesn't have enough compression to start. Thoughts, suggestions, and related experiences are appreciated as always.
Long story short, I bought a 353,000 mile 1997 Honda Civic 1.6 very cheap from a friend's brother because someone he knew severely overheated it, causing the timing cover to melt and jam the belt to the point of jumping several teeth and no longer starting. While he was trying to diagnose the problem, he blew out the ignition coil by cranking the engine with the spark plug wires off and decided he had enough after it sat for over a year and was going to scrap it, so I made an offer expecting to have to rebuild or replace the engine and here we are.
Having quite a bit of Honda experience, I immediately had an idea of what likely happened when I saw the melted timing cover and belt covered in melted plastic, so I checked the timing and found that it was off. Once I reset the timing and replaced the dead ignition coil with a spare I had, I tried starting it. Sounded like it had virtually no compression, it didn't even attempt to fire despite having fuel, proper timing, and spark. Starting fluid didn't help nor did cranking it at wide open throttle with the fuel injectors unplugged to clear any possible flooding.
Somewhat disappointed but not surprised, I got out my compression gauge and tested each cylinder and got 95, 165, 70, 70. That explains why it didn't start. I then added 2 cap fulls of oil to each cylinder, briefly cranked the engine, and retested the compression. This time, I got 120, 215, 90, 130. Feeling pretty confident that would be enough for the engine to run, I put the spark plugs back in, plugged in the fuel injectors, and tried starting it and it fired right up and ran well! I quickly drove it around the block without incident, the compression no longer sounds bad/uneven while cranking, and it starts right up now. I haven't retested compression yet because of the sketchy timing belt though. I ordered a new belt and will retest the compression once the belt arrives and I have a chance to change it and whatever other timing components were damaged.
I always knew that the oil film on the cylinder walls helps seal the rings by filling in the microscopic gaps, but this is the first time I saw an engine lose so much compression it sounded blown and wouldn't even attempt to fire just because someone flooded it months back and washed the oil off the cylinder walls. I had no idea that was even possible and I have been working on cars my whole life.
Anyways, just thought I'd share that odd experience in case anyone else runs across an engine that doesn't have enough compression to start. Thoughts, suggestions, and related experiences are appreciated as always.