Water Pump Leak Help Me!!!

[surfdaddie]

I got a 1989 Johnson 9.9 I bought it from some guy in the paper. The motor runs excellent I recently installed a new waterpump, the housing, seals and all (yes I did install a new impeller). I got the thing put in the pump went on easy and everything. I went to start it up and not much water was coming out of the top there was a some what steady stream coming out the hole and it eventually dies out so I took it apart took the lower unit off and everything I blew some air with a compressor through the water pick up tube in the bottom and the air seems to leak out some where. I believe that water and air is coming out from the top of the copper tube by the power head. Does any one have any Suggestions on how to fix this?

 

[OBJ]

Re: Water Pump Leak Help Me!!!

Hi Knut...welcome to iboats.<br /><br />What you are probably hearing is the air going through the block and back out the exhaust tube. <br /><br />When you assembled the impeller to the drive shaft, are you sure the impeller key was in place before putting the housing on?<br /><br />How long did you run the engine and did it overheat? <br /><br />Sometimes the tell tale hole will plug up with debris. Try running a piece of wire up into the hole or with the engine off, blow compressed air through it. <br /><br />Keep us posted....thanks.

 

[jim dozier]

Re: Water Pump Leak Help Me!!!

Clamp a garden hose onto the end of the water tube where it joins the water pump and check the flow of water through the engine. Look up at the top of the water tube with a flashlight for leaks. Water should exit the pee stream and the exhaust. I'm not sure on this engine but you may have to remove the themostat temporarily during this test to check the normal running temp water flow.

 

[R.Johnson]

Re: Water Pump Leak Help Me!!!

On these 9.9, and 15 HP engines, if the engine overheats, it can melt the upper grommet on the water tube. When serviceing the water pump, it's best to replace the whole assembly, not just the impeller. These pump's are a positive repacement at cranking, and slow speeds, meaning they will pump air, and are self priming. At the higher speeds they are a centrifugal pump as the impeller blades bend back, and they are more of a circulator. If you take a pump apart you can see that the impeller housing, and plate can become deeply grooved, or worn.Then they will no longer pump air, or be self priming.

 

[surfdaddie]

Re: Water Pump Leak Help Me!!!

I took it apart again and every thing seems to be fine. The impeller seems to be ok with the new housing that I installed a week earlier before i posted my question. I ran this motor for over 30 min in a test tank. Not much water was coming out of the top hole but plenty of hot water was coming out of the bottom exaust hole. The motor ran great and everything. The motor didn't overheat. How do you know if you have overheated the motor. I think i will continue to operate the motor are there any signs I can look for to tell if the motor is overheating

 

[OBJ]

Re: Water Pump Leak Help Me!!!

Knut....with the engine running at idle, touch the flat area on top of the block just in front of the head. You should be able to lay your fingers there for several seconds before having to remove them. If you can do this, you temp should be good. If you touch the area and can't lay your fingers there, the engine is overheating. <br /><br />On the reverse side, if it stays cool and shows no signs of warming up, you may need to replace the t-stat. You don't want to run the engine like this either.