Evinrude 4 hp weak impeller output

[Les Faulk]

1994 Evinrude 4 hp Deluxe motor. It had very low hours (20-30) when I took it in trade, and had been sitting for a few years. Runs great, but the tell-tale water stream wasn't very strong. More of a dribbling stream than a strong one. Removed and replaced the impeller with a new one and got the same result. Blew compressed air through it, but no improvement. Old impeller was intact and not showing much wear. Is this kind of output normal for this motor??<br />Thanks for any help on this.

 

[haddles]

Re: Evinrude 4 hp weak impeller output

I had the same concern as you. My 5hp Johnson does the same thing. I figure it must just be due to the small capacity of the motor and cooling system as the stream is at best luke warm after some hard running. I also have a 4hp Yamaha 4 stroke and that does it as well.

 

[Goodoleboy]

Re: Evinrude 4 hp weak impeller output

If it were me I would disconnect the rubber tube that goes to the little plastic outlet and then see if you have a good sream of water.<br /><br />If not then you most likley have an obstruction some place between the impeller and the tell tale. <br /><br />Or perhaps a poor fitting of the water outlet tube into the top of water pump.<br /><br />The water from tell tale does not circulate thru block or thermostat. It comes straight from the water tube and back out into the lake.<br /><br />The small restriction of tell tale is why it divertes other water to cooling pasages of block. In other words its a pressure and resistance action. <br /><br />Your tell tale is a visual check in order to assure you the water pump is indeed working. <br /><br />It should not warm up but very little ever. You have a blockage or leak, Most likley a blockage of some sort.<br /><br />If all things are working proprely your tell tale should be quite good even at idle. and a little stronger at higher RPM,s <br /><br />Good luck!

 

[Les Faulk]

Re: Evinrude 4 hp weak impeller output

Hey, thanks for the ideas. I couldn't find the usual plastic/rubber tube that runs from the block to the tell-tale hole. Seems that the tell-tale hole comes directly out of the block. Poked some wire around in there and blew it out. Water coming out seems to be warmer than it should be...more than luke warm, but not hot. Think I'll pull it back apart and check more carefully for obstructions and alignment of the water tube. Not a big deal.<br />Thanks again.

 

[Joey One]

Re: Evinrude 4 hp weak impeller output

I have a '94 Evinrude Deluxe 4 HP which I love. It does not have a rubber tube or pee hole from the lower motor cover. Instead the cooling water goes into the exhaust housing; some of it goes thru a hole in the exhaust housing at low pressure and the rest goes down the housing after passing some holes where you can see a small spatter.<br />The description you gave appears to be normal.

 

[ratracer]

Re: Evinrude 4 hp weak impeller output

As you know the peehole is on the midline of the motor behind the shaft and it pees straight down.<br /><br />The pee should be enough at idle where the water runs freely but the flow won't be particularly strong. Certainly not like what you'd normally see from say a properly running 9.9/15HP. <br /><br />Even at WOT the pee stream won't have a whole lot of pressure to it (I have a '91 Johnson, same thing) and although the water will be warm it's not too warm to be uncomfortable on the hand. Your motor sounds about right to me.

 

[Les Faulk]

Re: Evinrude 4 hp weak impeller output

Hey, thanks guys. I do feel better about it now. I was kind of comparing it to my 9.9, and that's what got me to worrying about it. Warm but not uncomfortable is a good description of what I'm getting out of it.<br />Should be good to go.<br /><br />Thanks again!