Low Compression Test Results
I tested with the same tester as you and got similar results, it lead me down a paranoid path thinking I'd be shopping for a new motor soon. Long story short, everything is fine and the car tested at leakdown numbers below like 5% and tested normal compression numbers on a different gauge.

Did you use a Harbor Freight leak-down tester or did you opt to go with something a little nicer? I'm pretty sure I've got a leak(s) based on the oil on the exterior of the engine. More than anything, before I continue doing work on the car (needs a lot of body work and misc engine work) I just want to make sure the engine is healthy since that's priority #1.
BTW see you are using a K&N filter many people consider using an OEM filter on these to be a must. Dont want to start another engine oil or filter debate though.
No, that leak is not a source of any low compression.
No, that leak is not a source of any low compression.
. For the air filter, it's the K&N filter that a lot of people on here recommend. I installed it about a year ago and it's still really clean (looks almost brand new) but I'll probably clean it again soon to be safe. Now that the car is getting to some pretty high mileage (187k and counting), I'll probably double check all the fluids since I have no idea when the last time the Transmission or Differential fluid were replaced (Clutch and Brake fluid are fine).
FYI, a leakdown tester won't find external oil leaks. It only finds internal 'air' leaks. It only tells you where your loss of compression is coming from.
From all indications you don't really have any loss of compression (we'll know for sure once you test with a good gauge). So a leakdown test isn't going to have any worthwhile results to offer.
From all indications you don't really have any loss of compression (we'll know for sure once you test with a good gauge). So a leakdown test isn't going to have any worthwhile results to offer.
+1 with the other guys -- I've used the HF tester and get similarly [low-but-consistent] results.
I always make the argument that consistency is all that matters, as opposed to the raw high numbers that people are chasing, but people just don't care.
Be careful with that o-ring replacement -- follow Billman250's instructions to the dot (you do NOT want to remove the bolt too much or you'll be screwed):
https://www.s2ki.com/forums/s2000-un.../#post23054279
I always make the argument that consistency is all that matters, as opposed to the raw high numbers that people are chasing, but people just don't care.
Be careful with that o-ring replacement -- follow Billman250's instructions to the dot (you do NOT want to remove the bolt too much or you'll be screwed):
https://www.s2ki.com/forums/s2000-un.../#post23054279
FYI, a leakdown tester won't find external oil leaks. It only finds internal 'air' leaks. It only tells you where your loss of compression is coming from.
From all indications you don't really have any loss of compression (we'll know for sure once you test with a good gauge). So a leakdown test isn't going to have any worthwhile results to offer.
From all indications you don't really have any loss of compression (we'll know for sure once you test with a good gauge). So a leakdown test isn't going to have any worthwhile results to offer.
+1 with the other guys -- I've used the HF tester and get similarly [low-but-consistent] results.
I always make the argument that consistency is all that matters, as opposed to the raw high numbers that people are chasing, but people just don't care.
Be careful with that o-ring replacement -- follow Billman250's instructions to the dot (you do NOT want to remove the bolt too much or you'll be screwed):
https://www.s2ki.com/forums/s2000-un.../#post23054279
I always make the argument that consistency is all that matters, as opposed to the raw high numbers that people are chasing, but people just don't care.
Be careful with that o-ring replacement -- follow Billman250's instructions to the dot (you do NOT want to remove the bolt too much or you'll be screwed):
https://www.s2ki.com/forums/s2000-un.../#post23054279
Where I live is between 500-1000ft. above sea level. I don't have specifics unfortunately so I can only go off a rough estimate. I think it is just the Harbor Freight branded Compression Test that is at fault, everything appears to be good as far as the engine goes.
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