The valves were adjusted 100miles prior to the tests.
Alright, so i took my car to the garage this weekend where they did a compression test and a leakdown test. Compression test came out as
1st:220
2nd:215
3rd:225
4th:210
But the leakdown test got my questioned
1st:13% leak
2nd: 10%leak
3rd:12%leak
4th:30%leak
I mean. How is it possible to have such good compression with such huge leakage in all cylinders? I was wondering what can be causing this ? Can it be caused by a leaking headgasket alone ? I have been losing quite a lot of coolant recently and there is quite alot of white smoke at idle and even after the car has warmed up - but much less. And if it can be because of the gasket, what can be the consequences of driving like that for quite a while?

 

bump

 

Sounds like a head gasket to me, expecially becuase of the white smoke you mentioned. Compression numbers alone arent the best thing to judge and engines condition on. Leak-down tests are better and yours is pointing toward the HG.

 

Now, another question arise, if it is the headgasket, wouldnt it be the same leakage numbers in all the cylinders ?
And do i risk anything by driving my car with a condition like that?

 

During leakdown test, the mechanic should be able to determine the cause of the leak, if not, give him these tips:

1. Apply 100 psi to cylinder on compression stroke
2. Remove air filter, if you hear air seeping into intake manifold, then it's an intake valve leak or broken intake valve spring
3. Put ear near exhaust pipe, if you hear air, then it's exhaust valve leak or broken exhaust valve spring.
4. Remove radiator cap, if you see bubbles, then it's the head gasket
5. Remove oil cap, if you hear air, then it's your piston rings.
6. Put ear near adjacent cylinders, if you hear air coming out of an adjacent cylinder, then it's head gasket.
7. Remove H22 from your car, send it to slomofo cuz he needs a new motor.

Edit: My head gasket was leaking oil and I was running dry at 10,000 rpms and found four valve stems in my catalytic converter with a huge hole in my #1 piston, a few months earlier my headgasket was burning coolant and my head cracked while I was on a freeway in the middle of the desert. So, to answer your question about driving with a bad head gasket... answer is NO, it is not safe unless you know which fluids you're losing and add them often.