DT-85 won't rev up

[Radar 1]

My son just got a boat with a 1988 DT-85 that will not rev over 2000 RPM when put in forward gear, but will get to 3000+ RPM in reverse. It idles fine and will rev up in neutral. So far we have put in a new water pump and thermostat, found out the throttle valve sensor was bad and replaced it and set the voltage, hard plumbed the gas line to the fuel filter, cleaned the fuel filter, and made sure the butterflies on the carbs are opening fully. Squeezing the fuel bulb makes no difference in the way it runs, and all 3 spark plugs are new and not showing any signs of not firing ( all the same color and not wet). Could it be one of the sensors ( oil flow, water flow or water temp) that is putting it in limp home mode, and is there a way to bypass

 

[99yam40]

Re: DT-85 won't rev up

need to check alarm system to make sure it is functioning properly.

And then see if timing is being retarded, I believe that is what safe mode does to limit RPM

Yes it could be any of what you posted, so test to see

 

[Radar 1]

Re: DT-85 won't rev up

need to check alarm system to make sure it is functioning properly.

And then see if timing is being retarded, I believe that is what safe mode does to limit RPM

Yes it could be any of what you posted, so test to see

There haven't been any alarms go off, in addition we have rebuilt the fuel pump and reset the low oil switch on the motor. How do you test the alarm system and is it possible to by-pass the sensors and see if the motor will reach full RPM?