Leakdown test results

[vongiese]

I did a leakdown test on my 89 Sei - 200K miles (just bought it recently). Cylinders 1,3,4 are about 87% and leaking from rings mostly. Cylinder #2 is at 75% and really leaking most from #4 spark plug hole! This would point to a head gasket if the cylinders were adjacent to each other but in this case cylinders 2 and 4 are not adjacent!
The number 2 plug is a little fowled compared to the others, but the little i've heard it run - does't sound like it's missing real bad....
Any ideas on what my problem is??
thanks!
mike

[vongiese]

My Bad - I mistakenly was checking the #2 cylinder when the dizzy was pointing at the #3 so the air was going thru open intake valves via intake manifold into open valve on #4.
My numbers for the leakdown test are backwards - 87% is really 13% leakage.
After I got the correct cylinders - I have one that seems to be around 20% leakage - all from rings (air coming out of oil fill hole).
I've not found any info on leakdown tests other foks have done on this site. I''ve read that 10% is about max leakage - more than that is bad.... Any thoughts?
I haven't done a leakdown test on anyof my other hondas for comparison.
mike

[88Accord-DX]

Not related to these older Accords' leak down tests in particular. I like to look at the compression numbers to make the next move... Most of the time with other vehicles, (OBD 2) anything past 10% will throw a mis-fire code.
The leakage might gradually decline some once your rings expand under normal operating conditions too, being you said the car runs ok.

[vongiese]

Not related to these older Accords' leak down tests in particular. I like to look at the compression numbers to make the next move... Most of the time with other vehicles, (OBD 2) anything past 10% will throw a mis-fire code.
The leakage might gradually decline some once your rings expand under normal operating conditions too, being you said the car runs ok.

So once you have the leakdown results - you think the compressions gives a better indicator of how bad the leaking is?
Good point on operating temps - guess i could try the leakdown when engine is warm....

mike

[steveko]

That's how you're supposed too test the compression with the engine at normal temp and throttle wide open.I would ground the coil out also.

[88Accord-DX]

So once you have the leakdown results - you think the compressions gives a better indicator of how bad the leaking is?
Good point on operating temps - guess i could try the leakdown when engine is warm....

mike

Compression readings give some insight on the situation at operating temperatures at a glance rather than a leak down test. The compression reading shouldn't vary more than 20%. Once it reaches the limit of variation of 20% or more, then your more than likely will start to notice some vibration from the engine. The balance of the engine has to be a certain percent with all compression readings.
Do another leak down test with the engine at normal operating temperature & see what you find, along with a compression test. Shoot them numbers back here & we'll talk some more.

[88Accord-DX]

After some more thought on this 13% leakage on the leak down test. What is going to happen over time, is the engine more than likely mis-fire until the rings expand (if they will improve the compression #'s & lower the leak down #'s ......


Soon it will eventually clog your catalytic converter.