assistance w/ troubleshooting a mid-80's Evinrude VRO 40 hp.

[JbuZZo]

hoping for some insight...I have a mid 80's Evinrude VRO (40hp) on a 16ft Alumicraft. I've had the boat for about a year and have had it out on small lakes between 20-30 times. Twice it's given me problems. 1st time last Oct. and it was raining, 2nd time, and it was raining...The cover it tight on it...

Symptom: At full throttle, it wants to 'bog down'. sounds like it's flooding almost...

fouled plug?

any ideas would be greatly appreciated.

[DaMoose]

Could be a fouled plug. I would also look at the temp sensor, on the back of the motor, and also the water pump. If it is getting to warm or the sensor is bad it will also do this. Although this should happen even when its not raining.

[JbuZZo]

yeah...that's the weird thing...it's only happened those 2 times...back in Oct. there was a buzzer/alarm going off as well...as that a temp alert?

(sorry but, this is my 1st boat and I am a novice that this stuff...)

[DaMoose]

The buzzer is for multiple things, one being oil low if oil injected, another is for temp. I had this happen on my 92 Johnson 40 hp, I changed the water pump and have not had another problem with it. There may be a small rock or object in the water pump housing, causing it to not always pump enough water to keep it cool.

[JbuZZo]

right on...I will check that, thanks DaMoose!

[boatfixer]

The difference between tose 2 engines is Mooses's 92 has the S.L.O.W system and if it overheats it will limit the engines power by cutting out the ignition to half of the cylinders. JBuzz's mid 80's does not have that as I believe that came about 91-92. What did the plugs look like? You also need to make sure all fuel line connections are tight and hoses are not cracked. A fuel line sucking air can aerate the gas in the line causing the alarm to sound as well as running lean causing the loss of power.