max 2200 rpm under load

[mccrea]

i have a pair of 1992 merc carburated engines and my port engine is causing havoc. even at the dock when in fwd or reverse with full throttle my rpm is maxed out at 2200 rpm. replaced plugs/ carbs clean/ linkages set properly/ fuel is clean with proper 50 to 1 oil. 3 days ago it ran perfect through 5000 rpm under load and now only in neutral can i exceed 2200 rpm/ is there a black box i need to look at.<br /><br />thanks for any help

 

[achris]

Re: max 2200 rpm under load

pair of 1992 merc whats? 2.2hp, 20hp, 200hp. ?????

 

[mccrea]

Re: max 2200 rpm under load

sorry left out merc 135 carb engines

 

[fishingdan]

Re: max 2200 rpm under load

Check for spark on all cylinders of the affected engine. Chances are that one or more cylinders have stopped firing. If all get spark, then you need to look at the carbs. <br /><br />Get ready for people to yell at you for running up the rpms in neutral. It will tell you next to nothing and could damage your engine. Without a load, the engine will freely rev to high rpms with or without all cylinders actually working.

 

[mccrea]

Re: max 2200 rpm under load

thanks<br />i get strong spark and plugs are firing/ engine was running great 3 days ago. has to do with something electrical im sure. i talked to a mechanic and he thinks its a high speed stator that has gone bad/ how can i test for this. <br />mike