only half throttle?

[kneedeep4829]

I have a 92 Johnson 25hp. When I give it throttle all the way it seems as if I am only giving it half throttle. Engine starts fine. I tried cleaning carb(so I thought as this might be the problem) is there anything else anyone has had exerience with? did I acceidntally hit a governer somewhere in the linkage?

any help is appreciated!

 

[samo_ott]

Re: only half throttle?

Is it a 2 or 3 cylinder? does it feel like it's dropping a cylinder? How many carbs are there? Do a spark test. did this just start? Compression all ok?

 

[kneedeep4829]

Re: only half throttle?

2 cyl 1 carb new plugs. does not seem as if it has dropped a cylinder. gets on plan no problem. still able to whip it around between trees in tight areas and has good acceleration.. just seems as if it is goverened or somthing as it runs fine up to half throttle then it will not go any faster.

 

[boobie]

Re: only half throttle?

Is the throttle plate in the carb opening up all the way ? You also may want to take an insulated pliers and pull one plug wire at a time when running and see if you get an equal cyl drop in power.

 

[watergecko]

Re: only half throttle?

Timing retarded? Try sync/link?

 

[Jogin]

Re: only half throttle?

at what RPM does it want to die out at? if its 2500 or so I am assuming its something with your cooling system, check your tell tale to see how warm the water is and check your impeller. If the tell tale water is pretty warm then you may have a blockage or your impeller just isn't working correctly. Have you checked your thermostat?

 

[kneedeep4829]

Re: only half throttle?

no thermostat. it is peeing the same amount of water as normal. warm after running for a bit but not hot what so ever. water pump was just replaced 10 hours ago

 

[Jogin]

Re: only half throttle?

what you need to do is go get either a thermometer that you can test the powerheads temp with or some thermomelt sticks, it sounds to me like you have a blockage in your cooling system somewhere, or it could even be that your over heat safety switch is going bad, 92 was the first year they put them in and i believe it was 25 horse on up. When the safety switch activates it ends up retarding the timing either at 2000 or 2500 rpm, it is their idea of making it so you can get going in your boat if you are in a dangerous, but if you ask me you can still ruin the powerhead.