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1981 70HP Johnson, no tell tale water output.

R

Robert Laughton

New member
Hello all. I'm a newbi here.

I've had this motor for 7 years and never had a problem - a great motor.

As my family has grown, I bought a bigger boat with I/O.

I started the motor for a buyer of the 70HP boat, and no tell tale water stream. It has always worked.

I dropped the lower, and all seemed fine: good impeller, engaged to the shaft (strange round pin on the driveshaft flat area - I've never seen one like that), a jet of compressed air into the tube going up from the pump confirmed no blockage through to the tell tale outlet. Water pick-up screens are clear, I can see daylight when I look down under the pump.

I put in a new impeller just becausae I was there, and the old one was at least 7 years old....no change.

Any ideas?

Thanks in advance,

Rob
 
Although you felt compressed air flowing out the plastic tell-tale outlet.... when running, shove a piece of single strand wire through it. It could simply be a piece of salt being forced by the water to clog it. Also check the rubber line and the first outlet at the engine.
 
Rob, welcome. Often times there will be a piece of debris somewhere in the indicator hose/fittings. I have seen air pass through, but when water is moving, it can pick up crap that air won't. The round pin on flat shaft is a good idea, its high quality stainless. The shaft is flat, so under stress there are no holes or weak points to crack or wear.
 
Thank you Jim and Joe,

I found the problem, boy what a dumb thing.

On the morning that someone was coming to look at the boat, I couldn't find find my muffs/flushers, so I went to my local marina and bought a new pair. I thought "$10, that was cheap". Well they were cheap all right. Although they seems to be working, in fact the rubber cups are so flimsy, rather than force water into the motor, it simply spilled out past the cups! I observed this while using the muffs with the lower removed. There was not enough pressure to raise the water up the 6 inches or so to the impeller! Oh well, it's fixed now. That was a head-scratcher.

Thank you all.

Rob
 
??----Think about it first.------When the impeller is NOT TURNING the vanes may block flow of water through the pump.-----The hose pressure simply lifts the cups off the motor and water spills out.
 
I just overhauled a 60 horse Evinrude last year and my muffs will push water out the pee hole without running the motor. I have my well pressure switch set below 50 psi. Sounds like the muffs didn't fit well, or the rubber was quite warm and held little pressure. I have a black garden hose and the hot sun will make the water hitting the muff cups so warm that they won't seal very well until the cold water hits.....firming up the cups, thereby making an effective seal. When the motor water pump starts, you will see a substantial increase in flow, the exhaust also helps push the water, of course. My well water is only 52 degrees in the heat of summer.
 
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