1992 MERC 40 4CYL SLOW

[twofishy4u]

I JUST BOUGHT A 1992 MERC 40 4CYL FROM A DEALER. THEY ASSURED ME IT WAS FLAWLESS. TODAY WAS MY 1ST DAY OUT. IT STARTED GREAT AND RUNS WELL, BUT IT WILL NOT GO OVER A COUPLE THOUSAND RPMS. IN NEUTRALL ITS FINE. IT IS ON A TEN FOOT SPEED BOAT SO IT SHOULD FLY, IT WONT EVEN PLANE THE BOAT! IT DOES NOT SEEM 2 BE A MISFIRE, IT RUNS 2 SMOOTH. ALL LINKS ARE OK AND CARB PLATES OPEN COMPLETELY. PLEASE HELP!!!!<br />DAVE

 

[Mark Grahovac]

Re: 1992 MERC 40 4CYL SLOW

The first thing i would do is replace the plugs.I had the same problem once. unit would start,idle,and rev-up good but would not plane out the boat. I replace a few other expensive items before I had found the real problem!Haha!