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Is it okay for engine oil to smell like gasoline?

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DEAR TOM AND RAY:
WHILE CHANGING THE OIL IN MY 1988 MAZDA RX-7, THE MECHANIC NOTICED A STRONG GASOLINE ODOR IN THE OIL (THE MIXTURE WOULD NOT IGNITE). TWO MAZDA SERVICE DEPARTMENTS ASSURED ME OVER THE PHONE THAT THIS WAS COMMON DUE TO THE DESIGN OF THE ENGINE. DOES THIS SOUND CREDIBLE?
ANITA

RAY: WELL, ANITA, IT SOUNDS INCREDIBLE, BUT IT ACTUALLY IS CREDIBLE. THE RX-7 HAS A ROTARY ENGINE, WHICH IS DIFFERENT FROM TRADITIONAL PISTON ENGINES. PISTON ENGINES KEEP GASOLINE AND OIL SEPARATE BY USING RINGS, WHICH CREATE A VERY TIGHT SEAL. BECAUSE OF THEIR DESIGN, THE SEALS IN ROTARY ENGINES ARE NOT AS TIGHT, AND IT'S NOT UNUSUAL TO HAVE SOME LEAK?AGE OF GASOLINE INTO THE OIL.

TOM: IT'S EVEN MORE LIKELY IF YOU MAKE FREQUENT COLD STARTS OR SHORT TRIPS. ON SHORT TRIPS, THE ENGINE NEVER GETS UP TO OPERATING TEMPERATURE, AND THE SEALS NEVER FULLY HEAT UP AND EXPAND. WHEN ENGINES ARE COLD, THEY USE TREMENDOUS AMOUNTS OF GASOLINE. ROTARY ENGINES USE EVEN MORE, WHICH SIMPLY INCREASES THE LIKELIHOOD THAT SOME WILL LEAK THROUGH THE COLD SEALS.

RAY: SINCE I CAN TELL THAT WE STILL SATISFIED YOUR CONCERN ABOUT THIS ANITA, HERE'S WHAT YOU SHOULD DO. FIRST ASK YOUR DEALER TO ANALYZE THE OIL AND FIND OUT WHAT PER?CENT?AGE OF IT IS ACTUALLY GASOLINE. GASOLINE HAS A VERY STRONG ODOR, AND IT CAN SEEM LIKE THERE'S MORE IN THE OIL THAN THERE ACTUALLY IS. IF IT'S LESS THAN AROUND FIVE PERCENT, IT'S PROBABLY OK. JUST CHANGE YOUR OIL EVERY 3,000 MILES TO MAKE SURE YOU'RE GETTING GOOD LUBRICATION.

TOM: BUT IF IT'S MORE THAN FIVE PERCENT, HAVE THE DEALER TRANSPLANT YOUR ENGINE INTO THE NEAREST TWO STROKE LAWNMOWER AND GIVE YOU A NEW ONE.
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