Bad piston rings - stop leak

[Jccck]

I agree, rebuild the engine.

Anything else is a bandaid

No point rebuilding the Engine, he doesn't even know if that's the problem.

A compression test tells you if a cylinder is loosing compression ( ie leak)....not enough evidence to simply suggest "bad rings"

Use a LEAK DOWN test to find out where it is leaking from ! Most mechanics should be able to do this

+1!

Cylinder Leakage Test.. Awesome way to determine 100% what is the cause of compression loss.
I don't know about 'most' mechanics though =P

Also, just because she blows some Smoke.. It could be many things, not just the Rings.
Infact something as simple as the PCV valve being blocked can cause pressure in the crank case forcing oil into the combustion chamber.. Which causes no damage and is fixed for as little as $20.