I GOT A 1990 150HP MARINER WITH AN OIL INJECTION SYSTEM. ENGINE RUNS FINE AT ALL RPM RANGES. THE PROBLEM IM HAVING IS WHEN I ACCELERATE OUT OF THE HOLE,I IMEDIATELY GET ONTO PLANE AND AFTER APPRX. 100 YARDS THE ENGINE LOSES POWER(AS IF I JUST TOOK MY FOOT OFF THE GAS PEDAL), RETURNS TO IDLE. IT WONT DIE BUT I PRESSED THE PEDAL AND NOTHING HAPPENS. I PUT IT IN NUETRAL AND I CAN REV IT JUST FINE. I WILL LEAVE IT IDLING FOR A MINUTE AND TAKE OFF OUT OF THE WHOLE SHOT AND AGAIN TRAVEL APPRX. 70 TO 100 YARDS AND IT DOES IT AGAIN. IT SOUNDS LIKE SOME SORT OF SAFETY FEATURE SHUTTING ME DOWN OR SOMETHING? MY HORN DOESNT BEEP AT ME AS FOR THAT MATTERS. THE HORN DOES BEEP WHEN I TURN KEY ON (ASSUMING WARNING SOUND SYSTEM IS WORKING)IT STARTED OUT TO BE AN INTERMITTENT PROBLEM, 6 ATTEMPS WHEN I FIRST GOT ONTO THE WATER THEN THE REST OF THE DAY IT RAN BEAUTIFUL. WENT OUT TO THE LAKE 2 WEEKS LATER AND IT WAS HAVING THE PROBLEMS ALL DAY. I HOPE I EXPLAINED THIS THE BEST I COULD ANY PLACE I SHOULD START FIRST WOULD BE APPRECIATED. THE MOTOR DOESNT MISS OR STALL OUT
<br /><br />The first possibility that comes to mind is the diaphragm fuel pump. They're easy to rebuild and kits are cheap. The rubber check valves like to pucker and leak.<br /><br />I've had the same symptoms with faulty primer bulbs. The check valves can stick and cause all sorts of weird things.<br /><br />If it can be done safely, pump up the primer bulb when it starts to slack-off. If it recovers, then you know there's a problem getting gas to the motor. There could be other leaks or clogs anywhere between the tank and motor. That's old enough where it could probably use a thorough inspection of the hoses and fittings, etc.