Suzuki: suzuki samurai problem, suzuki samurai, coolant leak

Question
hallo.

i have got suzuki samurai with this problem.:

first it was running good..suddenly it started to produce an oilishy smokes from exhaust pipe.

after that problem occured, in the morning it starts on time but after it runs awhile it has hard start..

i checked the plugs i found three of them have got some oilishy..i decided to replaced them all with the new ones..but after it run awhile i checked again the plugs and i found the same problem.

but the car does not lost its pulling power..

what could be a problem?

Answer
A cylinder leak test will determine if it is a piston ring sealing issue.
If it is not piston rings, check the crankcase venting system.
Is the smoke whitish or bluish?
If white, does it have a sweetish smell?  If so it could be a coolant leak.
If bluish, it is usually engine oil.