2009 Merc Scorpion 350 Water pump not pumping

rockb

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2009 Mercury Scorpion 350 Water pump not pumping.

To run on the trailer I remove the top of the strainer and put the hose in the top. Normally I just leave the through hull open and let the extra water flow out the bottom. I have never had a problem with this in the past.

I just changed the impeller. Upon initial start up the pump was not pumping at all.

I took the pump off again and verified (by looking in the input and output ports) that when I spin the pulley the impeller is turning.

Then I put the pump back on and closed the through hull and turned the water hose on. The strainer fills and starts overflowing into the bilge. I fired up the engine and and the water never stops overflowing from the strainer. So I put my hand over the strainer to basically cap it off as best I can and water starts shooting out in between my fingers and then stops. The water starts flowing through the pump. Then it squirts out, then flows through the pump, and the cycle continues. I remove my hand and it continues flowing out of the strainer and a little while later the wife indicates that barely any water is coming out the exhaust (Temp is at 160). I cover the strainer and water starts going through the pump, cycle continues) and the temp drops to 153.

Is this normal and I never noticed it before because the excess water is normally flowing out the bottom of the boat or is there an issue?

Motor is a 2009 Mercury Black Scorpion 350 EFI. Pump is a 862914C. I was not positive about the impeller but from what I could come up with online it looked like a 47-862232A. I compared it to the one I took out and it looked like the same part to me.
 

Bondo

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70,468
Ayuh,.... You should find a Better way to feed it water, as the raw water pumps won't Suck water, they're a flooded entry push pump,....
The tiniest air bubble, 'n the prime is lost,...

Donno what happened here with this new forum software, but,....
I merged 2 of yer threads, 'n deleted the 3rd,....
Donno how my post got stuck in as a comment,....
Hope it don't short My post count,....

Strange,...... very, Very Strange,.....
 
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rockb

Petty Officer 2nd Class
Joined
Dec 31, 2009
Messages
113
To run on the trailer I remove the top of the strainer and put the hose in the top. Normally I just leave the through hull open and let the extra water flow out the bottom. I have never had a problem with this in the past.

I just changed the impeller. Upon initial start up the pump was not pumping at all.

I took the pump off again and verified (by looking in the input and output ports) that when I spin the pulley the impeller is turning.

Then I put the pump back on and closed the through hull and turned the water hose on. The strainer fills and starts overflowing into the bilge. I fired up the engine and and the water never stops overflowing from the strainer. So I put my hand over the strainer to basically cap it off as best I can to force water through the hose to the pump and water starts shooting out in between my fingers and then stops. The water starts flowing through the pump and I can feel a suction pulling down on my hand. Then water squirts out, then flows through the pump, and the cycle continues. I remove my hand and it continues flowing out of the strainer and a little while later the wife indicates that barely any water is coming out the exhaust (Temp is at 160). I cover the strainer and water starts going through the pump (cycle continues) and the temp drops to 153.

Is this normal and I never noticed it before because the excess water is normally flowing out the bottom of the boat or is there an issue?

Motor is a 2009 Mercury Black Scorpion 350 EFI. Pump is a 862914C. I was not positive about the impeller but from what I could come up with online it looked like a 47-862232A. I compared it to the one I took out and it looked like the same part to me.

TOW_SPORTS_INBOARD_-_MX_6_2_BLACK_SCORPION.jpg
 
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alldodge

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To run on the trailer I remove the top of the strainer and put the hose in the top. Normally I just leave the through hull open and let the extra water flow out the bottom. I have never had a problem with this in the past.

I just changed the impeller. Upon initial start up the pump was not pumping at all.

I took the pump off again and verified (by looking in the input and output ports) that when I spin the pulley the impeller is turning.

Then I put the pump back on and closed the through hull and turned the water hose on. The strainer fills and starts overflowing into the bilge. I fired up the engine and and the water never stops overflowing from the strainer. So I put my hand over the strainer to basically cap it off as best I can to force water through the hose to the pump and water starts shooting out in between my fingers and then stops. The water starts flowing through the pump and I can feel a suction pulling down on my hand. Then water squirts out, then flows through the pump, and the cycle continues. I remove my hand and it continues flowing out of the strainer and a little while later the wife indicates that barely any water is coming out the exhaust (Temp is at 160). I cover the strainer and water starts going through the pump (cycle continues) and the temp drops to 153.

Is this normal and I never noticed it before because the excess water is normally flowing out the bottom of the boat or is there an issue?

Motor is a 2009 Mercury Black Scorpion 350 EFI. Pump is a 862914C. I was not positive about the impeller but from what I could come up with online it looked like a 47-862232A. I compared it to the one I took out and it looked like the same part to me.

While your method will work in most cases it is far better to use something like fake-a-lake attachment. Pouring water into the strainer is ok but there is not enough water pressure to stop an air pocket. There is also the issue of the garden hose may not be supplying sufficient water volume. Your engine pump can pull more water then many city water supplies can provide. Your using the correct parts for your pump, and my thought is there is air throughout your engine and the impeller is almost running dry. I would recommend checking the newly installed impeller. Then either use a fake-a-lake adapter or pull the hose off the strainer and connect the garden hose directly. Maybe put another valve and quick connect on the hose or strainer cap
 

rockb

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While your method will work in most cases it is far better to use something like fake-a-lake attachment. Pouring water into the strainer is ok but there is not enough water pressure to stop an air pocket. There is also the issue of the garden hose may not be supplying sufficient water volume. Your engine pump can pull more water then many city water supplies can provide. Your using the correct parts for your pump, and my thought is there is air throughout your engine and the impeller is almost running dry. I would recommend checking the newly installed impeller. Then either use a fake-a-lake adapter or pull the hose off the strainer and connect the garden hose directly. Maybe put another valve and quick connect on the hose or strainer cap

I went to Lowes today and got some pipe that will hopefully fit in the hose that goes from the strainer to the pump ( I was there for something else and have never measured the hose). If it fits I will attach an adapter to that pipe to connect a water hose and have pressure to the pump (should provide the same function as a fake a lake).

I am surprised that there has to be pressure to stop an air pocket. When the boat is in the water there is no pressure on it. I can remove the strainer with the sea-**** open and water does not pour out of the top of the strainer. It is an inch or two above the waterline.
 
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Fun Times

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I went to Lowes today and got some pipe that will hopefully fit in the hose that goes from the strainer to the pump. If it fits I will attach an adapter to that pipe to connect a water hose and have pressure to the pump.
To try and help, the standard size hose on your engine model is 1-1/4" I.D. Good luck.:)
 

rockb

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I" PVC pipe and a 1" to 3/4 thread adapter worked. When I applied pressure I heard water flowing through the engine and water started flowing out of the ehaust (engine not running). Started up the engine and the temp slowly climbed up to 152 and hovered there. Then I put it back the way it was. Closed the seacock and started the water. Strainer filled up and started overflowing. I started the motor and the strainer went to about half full so I know that the pump is sucking water. Then the strainer filled and began overflowing and never stopped. Water was not coming out of the exhaust. Temp climbed to 184 slowly. I figured the thermostat should have opened by then and water would be sucked up and I shut it down.

What should the normal operating temp be at idle in neutral (RWC)?
 
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alldodge

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I" PVC pipe and a 1" to 3/4 thread adapter worked. When I applied pressure I heard water flowing through the engine and water started flowing out of the ehaust (engine not running). Started up the engine and the temp slowly climbed up to 152 and hovered there. Then I put it back the way it was. Closed the seacock and started the water. Strainer filled up and started overflowing. I started the motor and the strainer went to about half full so I know that the pump is sucking water. Then the strainer filled and began overflowing and never stopped. Water was not coming out of the exhaust. Temp climbed to 184 slowly. I figured the thermostat should have opened by then and water would be sucked up and I shut it down.

What should the normal operating temp be at idle in neutral (RWC)?

You should not have water coming out the exhaust with the engine not running. The seawater pump is a positive displacement type pump. This means there are no gaps where air or water can pass. It has to be this way for the pump to be able to suck water while running. With water being able to make it past the pump, the housing or the impeller vanes are damaged. From your first post you indicated the pump was not pulling water out of the strainer, so in those few seconds the impeller could have been damaged
 

rockb

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Messages
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You should not have water coming out the exhaust with the engine not running. The seawater pump is a positive displacement type pump. This means there are no gaps where air or water can pass. It has to be this way for the pump to be able to suck water while running. With water being able to make it past the pump, the housing or the impeller vanes are damaged. From your first post you indicated the pump was not pulling water out of the strainer, so in those few seconds the impeller could have been damaged
That is what I was afraid of. Looks Like another $40 for a pump if I go local.
 

rockb

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Took pump apart. Impeller looks like it did when I put it in. No evidence of wear.
PanamaCityBeaches-20140819-00215_zps1f9e3fac.jpg


I compared it to the impeller that I took out. It had a small rubber button that went on the top of it covering the shaft hole. I did not see one of these with the new pump. I admit it could have been hiding in that little plastic bag the impeller was in but I cannot find that bag now.
IMG-20140819-00216_zps1ef41b0e.jpg


Here is a picture of the plate that goes over the top. It definitely has some grooves in the plate. Not sure if these are supposed to be there or not.
IMG-20140819-00217_zps98d08e40.jpg
 

Bondo

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Ayuh,.... Did ya find ALL of the missin' pieces of the old impeller,..??

The end plate, should Not have groovin' like that,....
 

Fun Times

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^+1 I would suggest getting another housing, get one of the plastic ones just remember not to over tighten. Need also the stainless steel wear plate, here is the kit.

http://www.iboats.com/Water-Pump-Ki...5621216--**********.411103092--view_id.172770
Oops wrong impeller kit for this model. That's for the older engine models. You could try sanding down the brass cover like seen in the link below.

http://clubsearay.com/showthread.ph...ing-Cover-Assembly-Bravo3?p=566642#post566642
 

HT32BSX115

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^+1 I would suggest getting another housing, get one of the plastic ones just remember not to over tighten. Need also the stainless steel wear plate, here is the kit.

http://www.iboats.com/Water-Pump-Ki...5621216--**********.411103092--view_id.172770


Howdy,

Last summer I had a plastic housing crack (luckily when I was putting the boat on the trailer to go home!!) and start spewing water in the bilge.

I replaced it with the Hardin marine stainless housing kit. http://www.hardin-marine.com/p-14544-stainless-steel-lifetime-sea-pump-overhaul-kit.aspx

It will never break again!
 

rockb

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I got the new pump housing cover. Got it installed and all is well.
 
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