Do you have an air compressor with a pressure regulator?
Do you own a compression guage with a quick disconnect at the guage end of the hose?

I just discovered that if I do the following I have a free leakdown tester.

1. Set the compressor regulator to 100psi
2. Remove the guage from compression tester (quick disconnect)
3. Use tire valve stem tool to remove check-valve from hose.
4. Thread compression tester hose into desired cylinder sparkplug hole (at TDC)
5. Connect compression tester hose to air supply.
6. Read pressure on regulator gauge. Subtracted from 100 = leakdown percentage.

Congratulations on saving $85.
The bad news is the six I just tested has about 18% leakage (bad valves).

-Ben M.

I made this one out of $20 dollars worth of Harbor Freight & hardware store parts.

Did you do the test w/ the engine cold? I got a reading of 12% leakage cold. That reading went to 3% w/ the engine warmed up.

Did you try it "wet"? Do the regular test and then add a couple squirts of oil to each cyl. If it improves, then it's your rings.