# Yamaha 2 Stroke weak stream



## HelthInsXpert (Jan 24, 2018)

I posted this question on the Trick my Skiff group on FB and got kinda crucified. I have always run my 2006 90 2-stroke on the flush attachment when I'm done fishing. I was told, in no uncertain terms, that this was a terrible practice and it should only be fired up on muffs or in a tub of water.

I went ahead and changed out my impeller the other day. But I still have what I consider a weak stream (I realize the impeller doesn't come into play if you flush the motor without turning it on). So I'm thinking that maybe I've got debris somewhere.

I've cleaned out the hose running to the head, and then cleaned out the nozzle coming off the head. Any other suggestions to figure out why the stream is weak when flushing (motor off).

Does anyone else run the motor from the flush attachment or is that pretty bad?


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## Smackdaddy53 (Dec 31, 2012)

You can absolutely run a 90 2 stroke with the hose attachment, I do it all the time, actually ran one in my yard a few days ago on the hose attachment for about 30 minutes. Trick My Skiff shouldn’t even be brought up on this forum unless you’re making fun of those ****.


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## Guest (May 17, 2019)

I believe the owners manuals will state not to run the motor on the attachment. Buy some salt away and do a series of flushes with it. Also, what did you lube the impeller with when installing it? Many people use grease and some use too much and it can cause low wp even with the new impeller.


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## HelthInsXpert (Jan 24, 2018)

Good call on the salt away. I put some vaseline on the impeller when I installed it, no grease though. 

One thing I thought of, you have to twist the impeller to get it into the cup. And I'm not sure I twisted it so that it would turn in the same direction as the shaft. I wasn't sure if it would turn on it's own after installation, or if there were any implications of possible having it spin 'backwards'? Any thoughts on that? I'm a bit new to boats/motors/etc. 

Didn't know Trick my Skiff was a joke, but I'll remember that!


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## Guest (May 17, 2019)

Pull the lower and inspect. If the vanes were in the wrong direction some of them might not have flipped to the right direction when the motor turned over/ran. This will cause weak wp! It will also damage the impeller!


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## Guest (May 17, 2019)

Vaseline acts like grease! Use a little dish liquid.


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## Surffshr (Dec 28, 2017)

Vaseline might eat that rubber. That’s why you don’t use it when wearing a jimmy hat chasing strange.


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## devrep (Feb 22, 2009)

saw palmetto extract...


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## SomaliPirate (Feb 5, 2016)

Boatbrains said:


> I believe the owners manuals will state not to run the motor on the attachment. Buy some salt away and do a series of flushes with it. Also, what did you lube the impeller with when installing it? Many people use grease and some use too much and it can cause low wp even with the new impeller.


So was I supposed to put the impeller in with lube on it? Am I going to screw up my motor? Got about 15 hours on the new impeller. Stream while running looks about like it did before. I guess I shouldn't have went in dry...


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## Smackdaddy53 (Dec 31, 2012)

I never lube the impeller when I swap them, don’t see a reason to, it’s gone after a minute or two anyway and only water lubricates it.


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## Guest (May 17, 2019)

SomaliPirate said:


> So was I supposed to put the impeller in with lube on it? Am I going to screw up my motor? Got about 15 hours on the new impeller. Stream while running looks about like it did before. I guess I shouldn't have went in dry...





Smackdaddy53 said:


> I never lube the impeller when I swap them, don’t see a reason to, it’s gone after a minute or two anyway and only water lubricates it.


Lube is not required, but it does make insertion easier!


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## DuckNut (Apr 3, 2009)

HelthInsXpert said:


> I put some vaseline on the impeller


When you take off the lower as BB suggested, replace the impeller with a new one because of the vaseline.

When you put it in place and are putting the housing over it twist the shaft while pushing the housing down. This will seat the vanes properly. Dish soap helps as do all of the junk your wife uses for her hair in the shower.


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## anytide (Jul 30, 2009)

weak stream vaseline.............



and stay off faceplant


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## jay.bush1434 (Dec 27, 2014)

There is no harm putting a little Vaseline on the ends of the vanes to help the impeller seat in the housing. Dish soap works well also. I use a tiny bit of grease on the vane tips since I am putting it on the water pump housing bolts and the lower unit bolt threads to prevent corrosion. Anyway, when you put the impeller on the shaft, turn the shaft clockwise as you push the cup down on the impeller. 

You don't use Vaseline on your jimmy hats because it is a petroleum based grease and that isn't good for the girl's hoo-hah. It won't hurt the neoprene rubber impeller.


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## jimsmicro (Oct 29, 2013)

There's no cooling water going to the impeller when you run it on a flush port only. You need to use muffs or you'll burn up your impeller because it's spinning 700 RPM while dry inside the impeller housing. I guess SOME water can make it back from the thermostat housing but most of it will escape out the prop, exhaust relief, and pisser before it makes it back down to the impeller. You also need to make sure you inserted the key correctly on the impeller and that the metal cup isn't worn or seated improperly. It can spin in the housing which is bad. Honestly for the price of a new cup it's easiest to just replace it when you change the impeller.


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## Smackdaddy53 (Dec 31, 2012)

jimsmicro said:


> There's no cooling water going to the impeller when you run it on a flush port only. You need to use muffs or you'll burn up your impeller because it's spinning 700 RPM while dry inside the impeller housing. I guess SOME water can make it back from the thermostat housing but most of it will escape out the prop, exhaust relief, and pisser before it makes it back down to the impeller. You also need to make sure you inserted the key correctly on the impeller and that the metal cup isn't worn or seated improperly. It can spin in the housing which is bad. Honestly for the price of a new cup it's easiest to just replace it when you change the impeller.


There’s water going to the water pump when you run it on the flush port, if there wasn’t it water wouldn’t come out of the hole in front of the shifter linkage. The water goes through the powerhead, down through the water tube, into the water pump, fills it up then fills up the water cavity and out the weep hole. That video I post earlier in this thread was one I shot of a motor that’s on a Whipray that’s sitting next to my Maverick right now. I just ran it twice this week and it pisses like a donkey on that same impeller. It would have burned up the water pump impeller a long time ago if it was running dry when I flush it and run it on the hose. It’s a 2008 90TLR, no different that the 2006.


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## jimsmicro (Oct 29, 2013)

There's no water coming out of your exhaust relief which suggests to me that in general there isn't enough cooling water. Honestly, I don't even see why you'd need to run it anyway. The point of the flush port is so that you don't have to. But its your motor and obviously you're getting away with doing it since you do it frequently. Probably not a big deal but I figure there's a reason Yamaha tells you not to do it.


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