Horn Problems

I have a 1993 225 Evinrude Oceand Pro(Model# E225TXET). If I take and hit the thorttle hard the VRO, Engine overheatin Horm sounds. I have Disconnected the Vro pump years ago so i know it is not the VRO. I am leavein the dock from a cold start so i doubt that it is overheatin. I have just rebuild all 6 carbs, changed the water pump, plugs, and the gearcase oil. I mix the oil and gas at a 50:1 ratio. Also the motor sat up for about a year.

Re: Horn Problems

You should still have the fuel obstruction switch connected to the alarm. That is a constant horn, just like the overheat.

It is a vacuum switch so look for some restriction in fuel supply before the carburetors.

Re: Horn Problems

I have noticed that i get a little fuel leakage arooud the primer solenoid. Could that be part of the problem?

Re: Horn Problems

Not as far as the vacuum switch/horn alarm is concerned. The switch is active when the pump cannot pull enough fuel through the fuel line to keep the carb bowls full, so it is on the fuel tank side of the switch. Look at clogged fuel tank vent, clogged fuel pick-up screen in the tank, sticking anti-siphon valve, clogged primer bulb valve, dirty in-line fuel filter, or too small fuel hose or fittings.

You will want to assure that there are no fuel leaks inside the engine cover - way to dangerous to ignore.

Re: Horn Problems

I unhooked the wire to that switch and the buzzer stopped, connected it back and it started again. The boat is brand new not a week old so i doubt seriously that is a restriction in the boat side. I talked to a mechanic and he said just unhook it that i do not need it if i am not running a VRO pump. What is your comment on that?

Re: Horn Problems

In my view, disconnecting an alarm of any type is like putting a piece of tape over the oil pressure light in your car. That alarm is telling you something. If may be serious and it may not be. But ignoring an alarm can cost you dearly. Keep in mind a fuel restriction alarm means the engine can be running lean. Lean is what burns down engines. Here is a classic example of where a factory service manual would be a benefit for troubleshooting the engine. You didn't say whether the horn quits sounding after warm up, or whether it is on as long as you are at full or nearly full throttle. If you have a stuck thermostat or poppet valve, it doesn't take long to overheat an engine. And just because you have a good strong telltale stream, does not mean the engine is cooling properly. It only means the water pump is pumping.

Re: Horn Problems

Well said, Silvertip.

The switch has nothing to do with the VRO/OMS system directly. It is there on V6 engines to protect the engine and would be present even with conventional lift pumps. There is too much restriction on the supply somewhere and you should find the problem and fix it. The motor will run better once you have done that.

Check to be sure that all of your fittings and fuel hoses are 3/8" or larger.

BTW, the 225 had a fuel filter at the engine. If you added a full sized filter at the tank, you don't need both. If you are running premix through a fuel filter outside of the engine filter, make sure that it is of the right type and large enough to handle the flow.

Re: Horn Problems

(Fuel Anti Siphon Valve)
(J. Reeves)

Many of the later OMC V/6 engines incorporate a fuel restriction warning via a vacuum device attached to the powerhead. If the engine overheats, or if you have a fuel restriction, the warning is the same.... a steady constant beep.

NOTE... Only the V/6 & V/8 engines have the above "Fuel Restriction Warning". The warning horn will not sound on the other models.

The fact that a engine is not overheating, but the warning horn sounds off with a constant steady beep, and that the rpms drop drastically would indicate that the engine is starving for fuel due to a fuel restriction. Check the built in fuel tank where the rubber fuel line attaches to the tank fitting. That fitting is in all probability a "Anti Siphon" valve which is notorious for sticking in a semi closed position. It will be aluminum, about 2" long, and the insides of it will consist of a spring, a ball, and a ball seat. If this valve exists, remove it, knock out those inner components which will convert it to a straight through fitting, then re-install it. Hopefully that cures the problem.

The above procedure will cure a restriction problem with the anti siphon valve as stated. BUT, it may also allow fuel to drain backwards to the fuel tank when the engine is not running (siphoning backwards) due to the fact that the carburetors/fuel pump etc are higher than the fuel tank. This condition is not an absolute as the valves in the fuel primer bulb usually prevent this backwards siphoning problem. However.... if this does take place, the cure would be to install a new anti siphon valve.